Renewable Energy Definition (With Examples)

Renewable Energy Definition (With Examples)

This is a very short guide that outlines the definition of renewable energy, along with some clarifications of what it is in comparison to other types of energy, and also includes some examples of different types of renewable energy.

 

Definition Of Renewable Energy

There’s many slightly different definitions of renewable energy.

Most definitions include the following components … renewable energy:

  • Comes from a natural source or natural processes
  • Comes from a source, that when used, doesn’t deplete, or can regenerate very quickly (either immediately, or within the course of a human life time)

It is called renewable because, if you compare it to an energy source like fossil fuels, fossil fuels take hundreds or even millions of years to form from the buried remains of decayed plants and animals, that are exposed to heat and pressure over that time. Once mined and used, these sources aren’t renewed quickly. They can eventually present scarcity issues, and issues with depletion of resources.

 

Modern vs Traditional Renewable Energy

Traditional biomass, such as the burning of wood for heat and energy, is considered a traditional form of renewable energy.

Modern renewable energy is generally all other forms of renewable energy (including modern bio fuel and modern forms of waste-to-biomass conversion).

 

Different Types Of Renewable Energy (With Examples)

The different types of renewable energy are:

Read more about the different types of renewable energy in this guide.

 

Renewable vs Clean/Green vs Alternative Energy

There is a difference between renewable, and green or alternative forms of energy. 

Nuclear is an example of an energy source that isn’t renewable (yet), because uranium has be mined to use it. But, nuclear is far cleaner in it’s operation stage (in terms of emissions and pollution) than energy sources like coal and natural gas.

Bioenergy is another example of an energy source that may be renewable in some ways, but, where crops, trees, and other organic matter has to be planted and grown, there are questions over the use of other resources (land, water, fertilizer, pesticide etc.), pollution/emissions, waste produced, and overall how sustainable some methods of bioenergy prodution are.

Read more in this guide about what green energy is.

Alternative energy is usually just an energy form that is different from the conventional energy that is used in a particular sector. For example, an alternative energy car might use renewable energy to power a hydrogen fuel cell car (as compared to a combustion engine car using petroleum or diesel).

 

Sources

1. https://www.bettermeetsreality.com/solar-pv-vs-solar-thermal-csp-comparison-what-they-are-differences-examples/

2. https://www.bettermeetsreality.com/onshore-vs-offshore-wind-energy-comparison-what-they-are-differences-examples/

3. https://www.bettermeetsreality.com/hydroelectric-dam-vs-run-of-river-vs-pumped-storage-hydro-energy-comparison-what-they-are-differences-examples/

4. https://www.bettermeetsreality.com/the-different-types-of-renewable-energy-sources-with-examples/

5. https://www.bettermeetsreality.com/what-is-green-clean-sustainable-eco-friendly-energy-what-are-the-different-types-sources/

The Importance Of Renewable Energy, & The Benefits & Advantages (Economic, Environmental, Social & Health)

The Importance Of Renewable Energy, & The Benefits & Advantages (Economic, Environmental, Social & Health)

This guide outlines why renewable energy is important to our future.

It also outlines the benefits and advantages of renewable energy economically, environmentally, and socially (including health benefits).

 

Summary – Importance Of, & Benefits & Advantages Of Renewable Energy

  • The importance of renewable energy for the future is significant. One of the main reasons is the fact that these energy sources won’t face the same depletion and scarcity issues that non renewable energy sources might
  • But, this is only one of many reasons. Renewable energy has different economic, social (and health), and environmental benefits and advantages, as well as other types of benefits and advantages
  • Perhaps two of the biggest issues (apart from depletion of resources) that renewable energy has the potential to help us address are climate change via reduced greenhouse gas emissions, and air pollution/air quality via reduced air contaminant pollution
  • Something that should be noted is that individual types of renewable energy all provide their own set of benefits, and pros and cons. For example, wind and solar may provide different benefits to hydropower and geothermal. Furthermore, there can be different types of bioenergy (which is considered a renewable source of energy), and the different types of bioenergy may provide different pros and cons to each other. So, the different types or energy production methods of an individual renewable energy source need to be considered too. This guide looks at renewable energy as a whole.
  • For the purposes of this guide, renewable energy sources are solar, wind, hydropower, geothermal, and wave and tidal energy. Bioenergy can also be classified as a renewable energy, but not all bioenergy processes can be classified as sustainable. Nuclear isn’t a renewable energy source, but it does have a relatively clean operational stage with little or zero emissions and air pollution.
  • Non renewable energy sources generally include fossil fuels like coal, natural gas, and oil. 

 

Why Is Renewable Energy Important?

Renewable energy is important for a number of key reasons. 

What makes renewable energy different from non renewable energy is that it generally comes from natural sources and processes, and it won’t deplete after use.

Compare this to non renewable energy like fossil fuels which often need refining processes, and take hundreds of thousands, and even millions of years to regenerate after being mined.

Immediately, we can see that renewable energy sources don’t face the same depletion or scarcity issues that fossil fuels might. So, they have the ability to provide us with sustainable energy sources going into the future.

But, there’s additional factors that make renewable energy important – the potential economic, environmental, and social benefits they provide.

 

Economic Benefits & Advantages Of Renewable Energy

Some of the economic benefits of renewable energy are:

  • Job creation (increase the total number of jobs)
  • Higher quality and safer jobs
  • A good ROI on investment in renewables
  • A trickle effect on other areas of the economy
  • Economic stimulus
  • Can reverse the poverty cycle in poorer regions
  • Trade, import and export benefits
  • More independence and control over energy, which leads to more independence and control over the economy for individual countries
  • More competition creating lower electricity prices
  • Creates additional and different sources of income for individuals
  • Increase locally sourced services
  • Saves costs having to address other issues caused by fossil fuel energy (environmental, health, etc)
  • Save on costs with increased energy efficiency and reduced consumption
  • Other indirect economic benefits

 

We’ve already written several guides on the economic impact of renewable energy:

 

Environmental Benefits & Advantages Of Renewable Energy

How environmentally friendly an energy source can be looked at:

  • Across the entire lifecycle of the energy source (from extraction, all the way through to use and any waste products)
  • Or, at a particular stage of the energy process e.g. during operation/during energy production.

 

Renewable energy in general tends to be more environmentally friendly than non renewable energy, especially fossil fuels, because:

  • The energy source doesn’t need to be mined (like coal, oil, and natural gas do for example … compare that to sunshine which we get directly from the sun for solar energy)
  • The energy source doesn’t need to undergo processing or human refinement (like for example refinement of crude oil into gasoline or diesel products)
  • Greenhouse gas emissions during operation are generally far lower, or zero
  • Air pollution and air contaminant emissions are generally far lower, or zero
  • There’s reduced, or zero waste products from energy generation (compare that to coal for example which produces coal ash, which contains heavy metals, just as one example)

 

Some of the main environmental benefits of renewable energy are:

  • Addressing Climate Change – fossil fuels tend to emit carbon dioxide and greenhouse gases during energy generation, and GHGs are thought to be the main cause of climate change and global warming. Renewable energy sources are clean in their operation with little to no greenhouse gases emitted.
  • Addressing Air Pollution – fossil fuels emit an array of air contaminants, which degrade air quality (the air that humans breathe in – especially around cities and heavily populated areas). Renewable energy does not pollute the air during operation.

Other environmental benefits of renewable energy can include:

  • Addressing Water Pollution – both mining of fossil fuels, and the discharge from power plants (including heavy metals and other toxic chemicals) can pollute the water. Renewable energy can severely reduce water pollution in these regards.
  • Addressing Land Degradation – mining of fossil fuels can cause land degradation, and other land issues.
  • Address Waste Pollution – wastes from fossil fuels like coal ash can compose a large and toxic % of a country’s waste stream. Renewables have little to no waste
  • Provide Better Ecosystems For Our Wildlife – water and air pollution, as well as the clearing of land for mining, are not good for the ecosystems that wildlife live in. 
  • Address Ocean Acidification and Warming – side effects of carbon emissions.
  • Reduce Acid Rain – a side effect of air pollution.
  • Other Environmental Benefits – there are sure to be other indirect environmental benefits of using renewable energy not mentioned above.

 

The above is not to say renewable energy has no environmental issues at all – every energy source has at least some environmental considerations. In addition to these environmental issues, the mining of precious metals (and their scarcity/depletion), and recycling energy storage batteries (from electric cars and for electricity energy storage) in the future may become bigger environmental issues.

 

Social (& Health) Benefits & Advantages Of Renewable Energy

Renewable energy sources:

  • Are some of the least dangerous and most safe forms of energy generation for humans. Outdoor air pollution is one of the biggest causes of health problems and increased mortality rates in some cities and countries. Using renewable energy sources can not only improve our health, but also decrease the number of energy workplace accidents
  • Can put less strain on our health systems
  • Can provide better and higher quality jobs compared to fossil fuels
  • Can reduce the political and power based wars that are fought over oil and fossil fuels
  • Can give energy sovereignty to less powerful States and countries
  • Can reach remote and rural areas, and help lift the quality of life in societies and countries worldwide

 

Other (Miscellaneous) Benefits & Advantages Of Renewable Energy

  • Save water (which is a precious resource) in energy generation – fossil fuel plants like coal plants use a lot of water in cooling towers and for other applications. Renewables tend to be far more water efficient.
  • Renewable energy seems to have a lot more potential left to increase performance and energy capabilities (to provide more benefits to society) with further technological breakthroughs compared to fossil fuels 
  • Renewable energy can be portable
  • Renewable energy can be used on an individual, domestic and large scale commercial/utility level – can be used as part of, or away from the grid. Lots of flexibility

 

Further Resources On Renewable Energy

 

Sources

1. https://www.bettermeetsreality.com/pros-cons-of-renewable-alternative-energy-now-into-the-future/

2. https://www.bettermeetsreality.com/pros-cons-of-fossil-fuel-energy-now-into-the-future/

3. https://www.bettermeetsreality.com/renewable-energy-vs-fossil-fuels-vs-nuclear-comparison-guide/

4. https://www.bettermeetsreality.com/which-energy-source-is-the-most-dangerous-harmful-which-is-safest/

5. https://www.bettermeetsreality.com/economic-impact-benefits-of-renewable-energy-clean-energy/

6. https://www.bettermeetsreality.com/the-different-types-of-renewable-energy-sources-with-examples/

7. https://www.bettermeetsreality.com/challenges-problems-with-transitioning-to-renewable-energy/

Transitioning Towards Renewable Energy – Solutions, Strategies & Considerations

Transitioning Towards Renewable Energy - Solutions, Strategies & Considerations

Renewable energy is becoming more prominent in the electricity (and eventually overall energy) supply of more cities and countries worldwide.

There are challenges and problems with transitioning to renewable energy.

But, there are also solutions and strategies involved in that transition, and that is what we have outlined in this guide.

 

Summary – Solutions & Strategies For Transitioning Towards Renewable Energy

  • Ultimately, every city, State and country’s energy mix and energy system is different. So each will have it’s own individual solutions and strategies (short and long term) when trying to integrate and transition to a higher share of renewables. These solutions and strategies should be based around the factors and variables that make up that place’s energy situation/scenario 
  • Some cities and countries already have a majority renewable energy mix for their electricity supply – so, these cities and countries show what is possible
  • Ultimately, a transition towards an increased use of renewable energy worldwide will require a balancing of various social, economic, environmental, and other types of priorities and factors. It will involve possible breakthroughs in aspects like energy storage and back up dispatchable energy sources. And, while it’s clear there are problems like variability/intermittency of renewable energy, and inadequacies of existing grids and infrastructure, it’s also clear that it’s likely solutions to the current problems of renewable energy can be developed in the future. In any transition, a hybrid flexible energy system that composes of different types of energy (fossil fuels, nuclear, conventional renewables, and modern renewables) might be required as a bridging system. It’s possible short terms costs and drawbacks might need to be tolerated, in order to receive the big picture, and mid to long term benefits that cleaner energy forms will deliver

 

Have Diversified, Flexible Energy Systems 

One of the big criticisms of renewable energy sources like wind and solar is that they can be variable and intermittent (creating numerous problems for power grids and meeting demand consistently). 

In cities, States or countries where the variability of renewable energy has lead to problems, sometimes the fact that the energy system isn’t diversified or flexible enough is one of the major causes.

A diversified and flexible energy system might have:

  • A range of renewable energy sources in the mix (wind, solar, hydro, geothermal etc.)
  • Dispatchable energy sources (that can ramp up and down quickly)
  • Energy storage (in the form of batteries, or pump storage hydro)

Although not ideal, a diversified and flexible energy system may also have coal, natural gas, nuclear, and conventional (as opposed to modern) renewables like bioenergy providing energy in small amounts, to provide complimentary power where required in the short term.

Less desirable energy sources can be phased out as required over the mid to long term as renewables and clean energy become cheaper, more competitive and more reliable to run by themselves.

If we use South Australia as one example, when they had their power black out, the State was using primarily wind, solar and combined cycle gas energy sources. They did not have large scale energy storage in place (to store energy from solar and wind sources), but have recently had a large scale battery built to store energy. Latest reports indicate it has prevented further blackouts. 

About.bnef.com optimistically reports that energy storage installations will increase exponentially up to 2040 for stationary storage and electric vehicles – and, this will come mainly as a result of sharp declines in the cost of lithium-ion batteries.

 

Upgrade Existing Power Grids & Infrastructure, & Build New Support Infrastructure

Existing power grids and energy infrastructure are generally designed and built for fossil fuels and existing energy sources. 

Power grids can be upgraded to handle fluctuating and increased loads, along with the ability to handle different types of energy requirements.

Existing infrastructure can be upgraded, as well as new infrastructure built, to cater to renewable energy.

Transmission lines, interconnectors, convertors, and other infrastructure can be built new for renewables.

For example, transmission lines are needed to get power from solar and wind farms to where it is required – these farms can be far from where the energy is required.

Interconnectors (used as a transmission link) can be used between States and countries if a particular place is exporting excess/surplus power to another. Germany has done this with Poland and the Czech Republic, and Australia does it between some of it’s States, just as two examples.

 

Consumer/Customer Demand 

Government support for renewables helps, but ultimately, renewable energy needs to be something that is in demand by the market, and supported by customers.

Demand drives investment and development, economies of scale, and long term cheaper prices and better products and services.

If the public wants more renewable energy in their energy mix, they should be willing to purchase electricity from renewable energy suppliers (over fossil fuels and other energy sources).

 

Government Action & Support

Over the long run, renewable energy is expected to continue to become cheaper, and competitive enough to be equal with, and even out compete fossil fuels from a price perspective (renewably sourced electricity is already contributing to lower electricity prices in some places).

Because renewable energy is still establishing itself in many markets, it needs short to mid term support from governments.

There’s a few ways this can happen:

Regulations/Standards

  • Like Portfolios that specify the minimum amount of each renewable energy source that must be used for a State’s electricity
  • Like licenses for power plants that stipulate emission and pollution standards

Incentives

  • Subsidies, tax breaks, concessions, credits, and other incentives for the development or use of renewables

Penalties

  • Carbon taxes, polluters taxes, and other penalties that discourage dirty forms of energy production (coal and gas plants have traditionally never paid a price for their negative environmental and social impact – but, this is slowly changing with how expensive new coal and gas plant technology is becoming which minimises pollution and emissions)

Something that has to be noted is that government action and support has the potential to destroy a competitive market and specific parts of the energy sector if not used properly. There needs be be a balance between supporting new clean energy technology, whilst still supporting competitive, reliable energy sources that meet a natural need and demand.

 

Provide More Certainty For Lenders & Investors

Risk of technology or projects, uncertainty in the future, and questionable profits and returns can all lead to less lending and investing in renewables.

Government support in the form of direct investment for research and development, loan assistance, and Portfolio Standards (guaranteeing a minimum amount of supply from renewables) can be a start.

But, there can be more done to provide certainty and favorable conditions for investors and lenders.

 

Consider The Makeup Of Existing Energy Markets, & Market Entry For New Clean Energy Competitors

In some countries and States, the energy market has been established for a long time now to cater to fossil fuel energy.

There can be many powerful fossil fuel related companies and organisations (mining companies, utilities and power plants, etc.) that can have an immense amount of control and success in the energy sector.

These things can make it hard for renewables in general, and new clean energy competitors to gain market entry and compete, without the necessary support. 

Greater understanding of how the market functions, and changing it to allow better communication between energy providers, and between suppliers and the end user (as well as the power grid and transmission operators), can help. 

Additionally, support for those trying to enter and compete in the market with certain types of clean technology, in the form of subsidies, grants and concessions, may help. 

What most people don’t realise is that fossil fuels have historically been subsidised, and continue to be subsidised heavily to this day (so, it’s not like fossil fuels are always cost competitive) in many countries.

Consider this from Cleantechnica.com: “fossil fuels have received government subsidies for 100 or so years. These days, fossil fuel subsidies reportedly total approximately $5 trillion globally each year. Despite tremendous health costs, climate costs, and countless premature deaths caused by pollution … . Renewable energy also receives subsidies, but not to the same degree.”

 

Continued Technological Research & Development

Renewable technology, especially hydropower, solar and wind, has progressed rapidly over the last few decades.

But, continued technological research and development can lead to even better performance, better capacity, new capabilities, cheaper prices, and more.

This may not be limited to just renewables either. Cleaner energy in general, such as nuclear, may benefit us in the future with further technological breakthroughs.

Public and private investment can play a big role in research and development, as well as consumer demand.

 

Electric Cars, & Electrifying Fossil Fuel Dominated Industries & Sectors

Renewable energy has penetrated the power sector (electricity generation) far more than any other sector.

But, other industries like transport, and heating and cooling, are still very energy reliant on fossil fuels.

A continued switching to electric and hybrid cars could help in the transport sector.

In heating and cooling, district heating or electrification of heat might help (swecourbaninsight.com).

 

Greater Awareness & Education For The Public & Government With Transparent, Independent & Non Partisan Data

It’s argued that the barriers to transitioning to renewable energy aren’t economic or technological, but social/cultural, political and institutional (with major points being that government officials don’t understand how important renewables are in addressing environmental and social issues, and the general public doesn’t know how reliable and beneficial they can be in the right energy systems). 

Data and information that is independent, objective and non partisan being spread to government representatives and the general public can provide an accurate view of renewable energy to these groups.

 

Digitalisation 

Digitalisation is the use of digital technologies to make things better.

The energy sector lags behind other industries in terms of digitalisation. 

Digitalisation in the energy sector:

  • … will go beyond the installation of “smart” electricity meters connected to the internet, or being able to remote-control household heaters with a mobile phone
  • … [it will include things like the] exchange of surplus power generation among neighbours and the activation of flexibility on smaller scales
  • Creating demand flexibility can only work via communication. This is where digitalisation can show its strengths
  • [Digitalisation can be vital in allowing renewable energy to penetrate the transport and heating sectors]

– cleanenergywire.org

 

Other Resources On Transitioning Towards Renewable Energy

 

Sources

1. https://www.bettermeetsreality.com/can-renewable-energy-replace-fossil-fuels-meet-demand-power-the-world-moving-towards-100-renewable-energy/

2. https://www.bettermeetsreality.com/challenges-problems-with-transitioning-to-renewable-energy/

3. https://www.power-technology.com/features/featureovercapacity-and-the-challenges-of-going-100-renewable-5872868/

4. https://www.ucsusa.org/clean-energy/renewable-energy/barriers-to-renewable-energy

5. https://www.swecourbaninsight.com/urban-energy/the-limits-to-renewable-energy/

6. https://www.bettermeetsreality.com/why-do-we-still-use-fossil-fuels-instead-of-renewable-energy/

7. https://cleantechnica.com/2018/01/26/renewable-energy-doesnt-get-subsidies-fossil-nuclear-sources-gotten-continue-get/

8. https://www.cleanenergywire.org/dossiers/digitalisation-energiewende

9. https://about.bnef.com/blog/energy-storage-investments-boom-battery-costs-halve-next-decade/

Challenges & Problems With Transitioning To Renewable Energy

Challenges & Problems With Transitioning To Renewable Energy (Arguments Against Renewables)

Cities and countries around the world are transitioning the energy sources for electricity towards renewable energy sources at different rates.

Inevitably, there are potential challenges and problems with this transition that can occur.

In this guide, we list and explain those different challenges and problems. 

Some of these problems and challenges are often used as arguments against renewables by those who support the use of other energy sources (fossil fuels, nuclear, and so on)

 

Summary – Challenges & Problems With Transitioning To Renewables

 

Capital Costs

The cost of renewable energy capital (i.e. – to build solar farms, wind farms, mega hydro dams etc.) can be expensive compared to some fossil fuel capital (ucsusa.org).

What tends to happen though, is that these upfront costs average out over time with the low running costs of solar and wind farms, and over the long term, renewables can be as cost effective as fossil fuels. This provides some certainty for investors over a 20 or 30 year period for example.

In addition to this, many sources quote the old prices of coal, natural gas and other fossil fuel plants. New fossil fuel plants with devices and systems for minimising carbon emissions and air pollutants can be far more expensive. Clean coal and CCS technology can also be expensive.

Add to this that renewable energy technology and equipment is becoming cheaper as demand increases and economies of scale kick in, and capital costs are becoming less of a challenge.

An asterisk to cost, is of course, that developed/wealthy countries and cities are going to have far more of a budget to finance renewable energy technology and systems than developing/poorer countries and cities. So, level of financing is an issue here too.

 

  • … there are estimates that the costs of moving the entire country to 100 percent renewable sources would be around $5.7 trillion, and a 2019 brief from the Institute for Energy Research estimates that the idea of getting to 100 percent renewable generation is “nothing more than a myth,” and that attempting to do would be a “catastrophe” for our country.

– wattsupwiththat.com

 

In some places like Australia though, the scenario might be different:

  • The cost to decarbonise the electricity system is lower than the cost of replacing the existing power system [replacing the existing coal fired generation with new coal fired generation] like for like

– reneweconomy.com.au

 

Also, as reneweconomy.com.au notes:

  • Over many years the electricity market has seen numerous technology changes driving prices.
  • An obvious historic example was oil fired generation to coal. Another shift was the move using transmission from small generators to large generation units.

Something we have to consider in lieu of this is that it costs money to set up, maintain and upgrade any electricity system – both new and existing. There would have been a time where there would have been high short term costs to build new fossil fuel generators, nuclear and associated infrastructure. With this in mind, short term costs for renewable energy may not be the problem it is made out to be as long as costs stabilise (adjusted for inflation) over time, and there are benefits to these newer energy sources that fossil fuels and existing energy sources aren’t providing.

Also, consider the subsidies, investment and government support fossil fuels have received through history (over the last hundred years or so). We must consider whether it’s a fair comparison for fossil fuels and renewable until renewables and greener energy has had the same amount of time, investment, support and development as fossil fuels has had.

 

Supporting Infrastructure

Existing energy grids and infrastructure like power lines are largely set up for fossil fuel energy.

It can be both time and money intensive to to build new infrastructure, upgrade power grid, build new transmission lines and interconnectors, build new convertors, and so on – all to support renewable energy or a changed energy mix.

However, some of these costs are more of a one time cost that benefits the energy system over the long term (the same way existing infrastructure and energy systems were originally paid for and built for fossil fuels)

 

Reliance On Government Support

At least in the short to mid term, some argue that renewable energy needs to support of governments to get into and compete in the market via subsidies, tax breaks, carbon tax (on other energy sources that pollute), schemes and concessions, credits, and so on. 

How much a government supports renewable energy can heavily influence it’s expansion and use. This support can’t waver from year to year – it really needs to be a long term commitment to help the technology get set up, develop and stabilise. 

We see different governments around the world supporting renewable energy, and even individual renewable energy sources, to different extents.

For example, even though the US isn’t a country that has majority of it’s electricity supplied by renewable energy sources yet, parts of the US like California, and the MidWest, have governments that support renewable energy in different ways.

 

Decentralization, Siting & Transmission 

Fossil fuel plants tend to be centralized in one place, where as renewables like solar and wind can be decentralized and spread out.

This presents two issues – siting, and transmission:

  • Siting – for every piece of land wind and solar occupy, there can be ensuing negotiations, contracts, permits, and community relations, all of which can increase costs and delay or kill projects. (ucsusa.org)
  • Transmission – power needs to get from where it’s produced, to where it’s needed. Transmission lines are needed, which take time to build and are costly, and they also need to be sites (ucsusa.org). The further away solar and wind farms are from where the energy they produce is needed, the more complications that can arise.

Solar is often classed as utility (solar farms) and distributed (solar panels on buildings and in residential areas). A decentralized system like this can also provide benefits, such as stabilising the power grid in the event there is an issue with the main energy system, but, also providing multiple points of energy generation in the event of a natural disaster or extreme weather events.

 

Intermittency & Variability

Renewable energy sources solar and wind are often called intermittent and variable sources of energy.

This is because the consistency of their energy supply is often determined by how much the sun is shining and how much the wind is blowing i.e. the quality of sun and wind conditions.

This can be a problem as there can be very little, intermediate amounts, or too much energy coming through at any one time or over a certain period.

In comparison, fossil fuel energy sources like natural gas and coal tend to be consistent because they rely on coal and gas resources supplies, which are always abundant and available.

Variability and intermittence can lead to a number of issues like:

  • the mismatch of energy supply with demand (electricity needs to be timed to be used at the time it is required, unless energy is stored in a battery),
  • blackouts,
  • uncertainty for other energy sources and operating at smaller scale (this means operators of these plants lose money and profits)
  • the phasing out of other energy sources (and shutting down of these power plants),
  • the requirement for back-up energy sources,
  • decreased investment in certain energy sources,

It really can be a domino effect with variability.

(In fairness though, there are things that can be done to address variability and intermittence, such as introducing market controls for a more stable energy market, introducing energy storage, introducing backup dispatchable energy sources, and so on)

 

  • “Intermittent wind and solar cannot stand on their own,” the brief concludes. “They must have some form of back-up power, from reliable coal, natural gas, nuclear units, storage capability from hydroelectric facilities, and/or batteries. Batteries of the size and scope needed for 100-percent renewables are unproven and not cost effective. Even if a 100 percent renewable future were feasible, the land requirements and costs of transitioning would be enormous and would require subsidies to ease the electricity price increases that would result.”
  • [A question with this study though is … this is limited to the US (and not other countries or States), and it doesn’t mention the environmental costs of fossil fuels (or social/health), it doesn’t mention the long term impact of renewables (only the short to medium term), and it doesn’t mention all the other benefits of renewables. So, if renewables are increasing electricity prices – is it for a justifiable reason or not?] 

– wattsupwiththat.com

 

Overcapacity

Over capacity is when there is an over supply/surplus of energy to the power grid.

This is usually caused by conditions with too much sun and wind providing too much solar and wind energy.

The impact of this can be a power grid that becomes unstable, and electricity prices that drop.

Germany is one example of a country that has experienced overcapacity as a result of variable solar and wind energy supply (power-technology.com)

 

Grid Stability

When the power grid is unstable, it can be due to a variety of reasons.

Specifically with renewable energy, it can refer to a surplus or lack of power supply that can impact availability of energy, but, can also refer to the ability of the grid to withstand load fluctuations from variable energy sources.

Countries like Poland and the Czech Republic have suffered grid stability issues from the transmission of surplus energy from the German power grid (power-technology.com)

 

Volatility Of Electricity Prices

Germany has experienced volatility of electricity prices when there has been a surplus of solar and wind power. Surplus electricity has forced prices negative in the past, forcing power plants to pay commercial customers to receive the surplus (power-technology.com)

Having said that, Germany has addressed this problem: ‘[volatile electricity prices] can be somewhat addressed by replacing the feed-in tariff subsidy with a market-responsive auction system based on pre-set RES capacity growth caps (power-technology.com)

Furthermore, wind and solar energy in South Australia has actually made the market for wholesale electricity prices more competitive with natural gas – leading to cheaper prices (abc.net.au)

 

Interference With A Competitive Market

There’s several ways the introduction of renewables, or the support of renewables by regulations and government tool, can interfere with the market.

Some of these ways includes:

  • If renewable energy portfolios require a minimum amount of renewable energy to be used, and for renewables to be used first, then other energy sources are capped at the scale they can operate (especially if they have to ramp up and down when there is a lack, or a surplus of energy)
  • There can be the closure of other energy sources if they aren’t supported or they can’t run at full capacity
  • Subsidies for renewable energy capital costs can be passed onto customers
  • Other more energy or cost efficient forms of energy can be forced out of the market even if they are more competitive (because renewables might be heavily supprted by non market support like regulations and government tools)

But, some people point to the support and subsidies fossil fuels have been receiving for years, and say that all the issues renewables might cause n interfering with a cost and economically competitive market could be said about fossil fuels too (especially when you take into account the environmental and social costs fo fossil fuels that aren’t priced).

 

Availability Of Back Up Dispatchable Energy Sources

A definition of dispatchable energy is: ‘Dispatchable generation refers to sources of electricity that can be used on demand and dispatched at the request of power grid operators, according to market needs. Dispatchable generators can be turned on or off, or can adjust their power output according to an order’ (wikipedia.org)

Because of the variable nature of renewable energy like solar and wind, when sunshine and wind conditions change, and energy supply of these sources are low or high, some energy systems require back up dispatchable sources of energy that can ramp up and down quickly to address baseload, low and peak demand.

Due to several factors, these back-up sources are usually natural gas or coal (nuclear less so). In Germany, having fossil fuel back up energy sources has actually lead to an increase in greenhouse gas emissions over the short term (power-technology.com).

 

Requirement For Energy Storage

Again, due to the variable nature of renewable energy sources like solar and wind in some places, dispatchable energy sources and/or energy storage may be used separately or in combination to provide energy when primary renewable energy sources are not providing enough power.

Energy storage can take several forms, with two of the more notable forms being battery storage, and pumped storage hydro energy.

Energy storage technology with batteries has technological and economic limitations with large batteries right now – the bigger they are and the more hours of energy they store, the more costly they are … they can be very expensive. They usually only have enough stored energy to last a few hours or for shorter bursts at the moment on the commercial scale. South Australia recently got a very large energy storage battery built to address recent blackout problems they had.

Pumped storage hydro energy involves storing energy in the form of water, pumping it up to a higher reservoir, and releasing that water downhill through turbines when energy is needed to generate electricity.

 

Political, Social, Cultural & Institutional Problems

Some sources indicate the problems with a transition to renewables aren’t technological or economic in some countries and cities, but political (politicians being supported by or being misinformed by fossil fuel companies), social (social misconceptions with the use of fossil fuel and renewable energies and what each can provide), cultural (biased cultural support for fossil fuels because of jobs, economic benefits and so on) and institutional (the energy industry is set up for fossil fuels and not renewables in many ways).

 

Penetration Into Transport, Heating & Cooling, & Sectors Other Than The Power Sector

Right now, most of the installed capacity, production of renewable energy, and consumption of renewable energy, penetrates into the power/electricity sector. Hydropower currently leads the charge in this regard of all the renewable energy sources.

Transport, and heating and cooling, though, are primarily fossil fuel powered right now. Transport, through the use of petrol and diesel-fuelled cars; and for heating, through the use of oil and natural gas boilers in buildings (swecourbaninsight.com)

It will be a challenge to electrify these sectors and penetrate them with renewable energy sources in the future.

 

Market Entry

The existing energy market in countries like the US is set up for fossil fuels and existing established energy sources, and these energy sources benefit from existing infrastructure, expertise, and policy (ucsusa.org).

Because of the market power of existing energy suppliers, it can be hard for renewables and individual clean energy competitors to enter the market and survive.

 

Unequal Playing Field

Renewables may not be entering a level energy market playing field in some countries.

Some argue in countries like the US, fossil fuels benefit from political influence, and receive direct subsidies (through subsidies, tax breaks, and other incentives and loopholes, and indirect subsidies (through not being punished for polluting for example) (ucsusa.org) 

 

Reliability Misconceptions

Because of the variability of wind and solar, some people think that they are unreliable.

But this may not be true:

  • Solar and wind are highly predictable, and when spread across a large enough geographic area—and paired with complementary generation sources—become highly reliable. Modern grid technologies like advanced batteries, real-time pricing, and smart appliances can also help solar and wind be essential elements of a well-performing grid. (ucsusa.org)

In addition to that, wind might be used more in the winter, and solar in the summer, and, there are new technologies being developed that might allow solar to generate energy at night time too.

 

Environmental Problems

Renewable energy is not without it’s own environmental issues (although, many argue that the environmental problems caused by renewables are minimal compared to those caused by fossil fuels). Just as a few examples might be:

  • Solar – solar farms use up a large land area (are land inefficient compared to fossil fuel power plants)
  • Wind – can be in the flight path of migratory birds and other flying animal species. Can also use up a large land area
  • Hydroelectric – the construction of dams, and the discharge of water can have a negative impact on water sources, the aquatic environment, aquatic wildlife, and downstream water users
  • Geothermal – can release waste steam and gas, can cause hydraulic fracturing, and can cause air and water pollution, amongst other issues
  • Wave & Tidal – can dislodge and have a negative impact on seabeds, and marine life
  • Bioenergy – uses land, can use fertilizer and pesticides (to grow crops for biofuel), uses water, and creates waste

– bettermeetsreality.com, and interestingengineering.com

 

Other Problems & Challenges 

  • Questions over whether renewable energy systems can scale up fast enough to a certain scale, by a certain target year
  • Adding turbines to some existing hydropower dams (for increased capacity) may be physically impossible
  • A potential shortage of precious metals int he future for renewable energy equipment and batteries (like nickel, cobalt, copper, lithium etc.)
  • The need for frequency control and the provision of inertia, price signaling and communication between distributors and the wholesale electricity market (Reneweconomy.com.au)
  • Older power engineers are attached to the concepts of base load, intermediate and peak load power stations … and cannot envisage a system that contains a large fraction of variable RElec and where demand can be modified almost instantaneously (Reneweconomy.com.au)
  •  The natural renewable resources each country or city has, and how much potential they have to expand e.g. Australia might have far more land and sunshine than other countries to expand their solar and wind equipment
  • Large hydro power projects like mega dams can be highly unpredictable in the design and approval stage, and can have feasibility issues
  • Renewable energy investment can be variable from year to year

 

Other Resources On The Challenges & Problems With Transitioning To Renewable Energy

There are many more challenges and problems than the ones we have listed above.

Some of the guides that list further challenges and problems are:

 

Sources

1. https://www.bettermeetsreality.com/can-renewable-energy-replace-fossil-fuels-meet-demand-power-the-world-moving-towards-100-renewable-energy/

2. https://www.power-technology.com/features/featureovercapacity-and-the-challenges-of-going-100-renewable-5872868/

3. https://www.ucsusa.org/clean-energy/renewable-energy/barriers-to-renewable-energy

4. https://www.abc.net.au/news/2018-12-07/study-shows-impact-wind-solar-gas-power-on-electricity-prices/10590876

5. https://www.bettermeetsreality.com/countries-cities-that-get-most-of-their-electricity-from-renewable-energy-sources/

6. https://www.bettermeetsreality.com/renewable-energy-vs-fossil-fuels-vs-nuclear-comparison-guide/

7. https://www.bettermeetsreality.com/pros-cons-of-renewable-alternative-energy-now-into-the-future/

8. https://www.bettermeetsreality.com/reasons-why-we-dont-use-more-renewable-energy-worldwide-barriers-obstacles-challenges-in-switching-over-to-renewables/

9. https://www.bettermeetsreality.com/the-challenges-with-chinas-transition-from-coal-to-natural-gas-renewable-energy/

10. https://www.bettermeetsreality.com/considerations-when-choosing-different-energy-sources-in-the-future-social-environmental-economic-practical-more/

11. https://en.wikipedia.org/wiki/Dispatchable_generation

12. https://www.swecourbaninsight.com/urban-energy/the-limits-to-renewable-energy/

13. https://www.bettermeetsreality.com/installed-capacity-production-consumption-of-renewable-energy-worldwide-by-country-by-source/

14. https://www.bettermeetsreality.com/pros-cons-of-renewable-alternative-energy-now-into-the-future/

15. https://www.bettermeetsreality.com/pros-cons-of-fossil-fuel-energy-now-into-the-future/

16. https://www.bettermeetsreality.com/impact-of-energy-electricity-production-on-the-environment/

17. https://interestingengineering.com/is-mark-jacobsons-plan-to-use-100-renewable-energy-feasible

18. https://wattsupwiththat.com/2019/05/02/researchers-say-renewable-energy-mandates-cause-large-electricity-price-increases/

19. https://reneweconomy.com.au/does-more-renewable-energy-mean-higher-prices-10310/

A Guide On 100% Renewable Energy (What It Is, Whether It’s Possible, Countries, Cities, By 2030, By 2050 + More)

A Guide On 100% Renewable Energy (What It Is, Whether It's Possible, Countries, Cities, By 2030, By 2050 + More)

You may have heard of the term 100% renewable energy.

In this guide, we discuss what is it, whether it’s possible, how different countries and cities are going with it, and how we might progress towards it by 2030 and 2050.

 

Summary – 100% Renewable Energy

  • 100% renewable energy is supplying 100% of energy by renewable energy sources, specifically by modern renewable energy sources like solar and wind. 
  • Some cities and countries already have a majority or full renewable energy mix in their electricity supply, so, 100% renewable energy is possible
  • Countries and cities that aren’t 100% renewable energy supplied in their electricity sector may have different plans for achieving 100% renewable energy by 2030 or 2050 (or another year that they have identified as their target year). 
  • Plans for 100% renewable energy differs by each country and city, and can depend on many variables and factors. The support of the government and government policy is a huge variable
  • There are models and studies that have been put together that can forecast the feasibility of different energy mixes for different cities and countries. There’s also websites that provide updates on the cities worldwide that are taking action on different sustainability measures in real time
  • It should be noted that some cities and countries may determine that 100% renewable energy isn’t ideal for them individually. A hybrid mix including fossil fuels and nuclear power may be ideal for different reasons

 

What Is 100% Renewable Energy?

100% renewable energy is supplying 100% of energy by renewable energy sources, specifically by modern renewable energy sources like solar and wind (but can also include other renewable energy sources like hydropower, geothermal, tidal and wave energy, and so on).

Right now, it primarily refers to 100% renewable energy supply in the electricity sector. 

But, in the future, it could also refer to 100% renewable energy supply in other sectors that are currently fossil fuel dominated, like transport, and heating and cooling.

 

Is 100% Renewable Energy Actually Possible?

Yes, some cities and countries already run on 100% renewable energy.

But, each country and city faces different challenges and problems with transitioning to a majority or full renewable energy supplied mix.

 

100% Renewable Energy Countries & Cities

Countries

  • According to wikipedia.org, the number of countries getting at least 90% of their electricity from renewable energy sources was 12 countries

The countries currently getting 100% of their electricity from renewable energy sources are:

  • Albania – 100%
  • Democratic Republic Of The Congo – 100%
  • Iceland – 100%
  • Paraguay – 100%

 

Cities

  • As of January 2018, 42 cities were getting at least 100% of their electricity from renewable energy sources, 59 cities were at at least 70%, and 22 cities at at least 50% (according to CDP.net’s interactive map)

 

100% Renewable Energy By 2030, & 2050

Studies & Reports Of The Future

Some studies and reports analyse factors like the year a city or country can reach 100% renewable energy, the challenges in getting there, what the energy mix might look like, and more.

 

Real Time Progress

Some websites provide information on the real time progress of some cities worldwide meeting certain sustainability measures. 

Examples are:

  • https://www.cdp.net/en/cities
  • https://www.c40.org/cities

 

Plans For 100% Renewable Energy

Each city and country has different plans for transitioning to an increased renewable energy mix. 

Government support is a big variable.

Some national and State governments are more pro renewable energy than others, for different reasons.

 

Sources

1. https://www.bettermeetsreality.com/can-renewable-energy-replace-fossil-fuels-meet-demand-power-the-world-moving-towards-100-renewable-energy/

2. https://en.wikipedia.org/wiki/List_of_countries_by_electricity_production_from_renewable_sources

3. https://www.bettermeetsreality.com/countries-cities-that-get-most-of-their-electricity-from-renewable-energy-sources/

4. https://www.cdp.net/en/cities

5. https://www.c40.org/cities

Hydroelectric Dam vs Run Of River vs Pumped Storage Hydro Energy Comparison: What They Are, Differences & Examples

Hydroelectric Dam vs Run Of River vs Pumped Storage Hydro Energy Comparison: What They Are, Differences & Examples

There are several different types of hydro energy set ups used to generate electricity globally.

In this guide, we compare hydroelectric dams vs run of river vs pumped storage hydro energy projects and power plants.

We look at what each is, their differences, and examples of each being used in the world.

 

Summary – Hydroelectric Dam vs Run Of River vs Pumped Storage Hydro Energy

  • Hydro energy is the use of running water to create electricity
  • Hydropower as a whole produces the most electricity of any renewable energy source – roughly around 50% of all electricity produced by renewable energy sources globally
  • There’s several different types of hydro energy – hydroelectric dams (built on rivers with an impoundment facility, dam and reservoir), run of river (may or may not have a dam – but can simply use flowing water without a dam or reservoir), and pumped storage hydro (using two reservoirs or water – one on a higher level and one on a lower level)
  • Essentially, they can be divided into hydro energy power set ups that use dams and reservoirs, and those that don’t
  • They can also be divided into large, medium and small sized hydro power plants, depending on the amount of electricity capacity they have (dam hydro power usually produces the most electricity)
  • Hydropower is expected to expand into the future, particularly in developing economies, but growth isn’t expected to be as strong as the last 5 years to one decade (investment and expansion will mostly be in solar, wind, and bioenergy)
  • Large and mega sized hydro projects can have some uncertainty regarding their funding, planning and construction – so growth and added capacity of hydro energy can be dependent on this
  • According to recent studies, there is potential for many new pumped storage hydro sites worldwide – pending on-site feasibility checks. Pumped storage hydro can be a good source of stored renewable energy in the future (especially as a backup to intermittent energy like solar and wind) 

 

What Is Hydro Energy?

  • Hydro energy is the use of running water to create electricity

 

The Different Types Of Hydro Energy, & How Each Works

Hydro energy can be broadly categorised into two types:

  • Hydro energy with dams and reservoirs,
  • and, hydro energy without dams and reservoirs

– irena.org

Utility scale and large hydro (hydro energy produced for electricity and energy utilities) usually involves dams and reservoirs, and small or local community/village, and run of river hydro usually doesn’t.

 

Beyond the above broad categorisation, utility scale hydro power plants can be divided into:

  • Impoundment/Dam (using an impoundment facility) – a dam stores water in a reservoir. Water is released from the reservoir through turbines, which activate a generator, and produces electricity. Dams can also serve other purposes other than just producing electricity, such as preventing flooding.
  • Diversion/Run Of River – part of a river is channeled through a canal or penstock. May or may not use a dam. [It helps if a river is chosen that has a consistent flow, otherwise, without a storage reservoir, energy will be variable and not consistent]
  • Pumped Storage – there is an upper and lower water reservoir. Water is stored in the lower reservoir, and when needed, is pumped up to the upper reservoir, and then released back down to the lower reservoir through turbines, which activate a generator, and produces electricity. [Pumped storage can actually store energy in the form of water, so, it can be a good backup to wind and solar energy for example]

– energy.gov

 

Diversion and run of river hydro generally has less negative environmental and social impact compared to large hydroelectric dams.

 

Something else to note is that renewable hydro energy might be becoming a type of hydro energy in the future. Currently, pumped storage hydro uses fossil fuels to pump water up to it’s top reservoir. In the future, renewable energies like wind and solar might provide the electricity to pump and power hydro power stations.

 

Large vs Small Hydro (& Medium Hydro As Well)

Globally, there’s no official definition of small, medium and large hydro, but each country has a guide of what they call the different sizes of hydro plants and projects.

Size usually refers to the energy/electricity capacity or generation of the hydro plant.

All of the largest hydro projects tend to be dams as they tend to produce the most electricity (this is true when you look up the largest hydro plants in the world, like the Three Gorges Dam that produces up to 22,500 MW for example).

To give a broad idea of how hydro plants and projects might be categorised by size:

  • Large – 10 GW (10,000 MW) and over
  • Small – 10-30 megawatts (MW)
  • Micro and Pico – in the kW range
  • Pumped Storage – some of the biggest pumped storage plants have a capacity of 1000 to 3000MW. New potential pumped storage sites discovered in recent studies have potential capacity to hold 2-150 GWh of energy (sciencealert.com) [and, 2 GWh converts to roughly 2000 MWh]

– wikipedia.org

 

Differences In The Different Types Of Hydro Energy – Cost, Efficiency, Capacity Etc.

  • Overall, hydroelectricity has been one of the cheapest forms of renewable energy (although solar and wind are challenging it)
  • Large Hydroelectric dams tend to be the most expensive to construct, but tend to have the greatest capacity for production (so, costs and returns can average out over the long term)
  • Large hydroelectric dams tend to have the highest social and environmental impact, whereas run of river and small scale hydro that doesn’t need dams and reservoirs tends not to be as intrusive or destructive on the natural landscape
  • Pumped hydro storage sites require land clearing, and once in use, may use fossil fuels to pump water up to the higher reservoir.
  • Dam and reservoir hydro plants offer energy storage and can ramp up quickly in terms of energy generation in times of peak demand – this is in opposition to run of river hydro energy that requires water be flowing (depends on a river that runs year round) in order to produce electricity

 

Global Installed Capacity, Production & Consumption Of Hydro Energy

Worldwide, hydro energy installed capacity, production and consumption stats are:

  • At the end of 2018, made up 50% of installed capacity for renewables
  • At the end of 2018, made up 15.8% of total global electricity production
  • At the end of 2016, was the most consumed renewable energy source for electricity

 

  • Between 2012 to 2018, solar PV led all renewables in annual additional installed capacity by a wide margin, followed by wind energy, hydropower, and all other renewables as a group behind that (including solar CSP/thermal)

– vox.com

 

  • At the end of 2015, the leading hydropower generating countries were China, the US, Brazil, Canada, India and Russia.

– worldenergy.org

 

Mixed Plant vs Renewable Hydropower Electricity Generation

In 2016, electricity generation from hydro power was:

  • Mixed Plant – 4,048,420
  • Renewable Hydropower – 0

– irena.org

 

Investment In Hydro Energy

In 2016, investment in small hydro lagged behind solar, wind and biomass globally.

Major hydro project investment can vary by year and can be unpredictable.

 

Future Of Hydro Energy

  • Hydropower capacity is expected to increase 125 GW [heading up to 2023] – 40% less than [the increase] in 2012‑17
  • One-fifth of overall growth (26 GW) is from pumped storage hydropower (PSH) projects

– iea.org

 

  • [it is thought there could be a lot of potential in pumped storage hydro in the future as new scans and studies of the globe have found hundreds of thousands of new potentially usable sites for pumped storage hydro]
  • [pumped storage hydro has the advantage of providing energy storage and baseload power as a complement to solar and wind energy]

– sciencealert.com

 

Examples Of Hydro Energy Power Plants Globally (By Type, Capacity/Size, Country Etc.)

  • Conventional Hydro Power Plants – https://en.wikipedia.org/wiki/List_of_conventional_hydroelectric_power_stations

Range from 1000 all the way up to 22,500 MW of capacity. 

China features heavily, having some of the biggest hydroelectric dams in the world, including the biggest – Three Gorges Dam, which is on the Yangtze River.

 

  • Run Of River Hydro Power Plants – https://en.wikipedia.org/wiki/Run-of-the-river_hydroelectricity

Highly variance in capacity of the major examples of run of river hydro plants globally.

Range from 16MW of capacity at a station in British Columbia, Canada, all the way up to 11,233 megawatts of capacity at Belo Monte Dam in Brazil.

 

  • Pumped Storage Hydro Plants – https://en.wikipedia.org/wiki/List_of_pumped-storage_hydroelectric_power_stations

Range between 1000 to 3000MW of capacity.

China, the US, Japan, Australia, Spain and France has some of the plants with the largest capacity.

 

Sources

1. https://www.irena.org/hydropower

2. https://www.energy.gov/eere/water/types-hydropower-plants

3. https://en.wikipedia.org/wiki/Hydroelectricity

4. https://www.vox.com/energy-and-environment/2019/6/18/18681591/renewable-energy-china-solar-pv-jobs

5. https://www.bettermeetsreality.com/installed-capacity-production-consumption-of-renewable-energy-worldwide-by-country-by-source/

6. https://www.bettermeetsreality.com/countries-that-invest-the-most-in-renewable-energy-what-they-invest-in/

7. https://www.bettermeetsreality.com/the-different-types-of-renewable-energy-sources-with-examples/

8. https://www.iea.org/renewables2018/power/

9. https://www.iea.org/newsroom/news/2018/october/modern-bioenergy-leads-the-growth-of-all-renewables-to-2023-according-to-latest-.html

10. https://en.wikipedia.org/wiki/List_of_conventional_hydroelectric_power_stations

11. https://en.wikipedia.org/wiki/Run-of-the-river_hydroelectricity

12. https://en.wikipedia.org/wiki/List_of_pumped-storage_hydroelectric_power_stations

13. https://en.wikipedia.org/wiki/Hydroelectricity

14. https://www.sciencealert.com/scientists-spot-530-000-potential-pumped-hydro-sites-to-meet-all-our-renewable-energy-needs

15. https://www.cnet.com/news/if-renewable-energy-can-power-entire-countries-why-isnt-everyone-doing-it/

16. https://www.abc.net.au/news/2017-02-03/pumped-hydro-and-its-potential-in-sa-explained/8233342

17. https://www.worldenergy.org/data/resources/resource/hydropower/

18. http://www.wvic.com/content/facts_about_hydropower.cfm

19. https://en.wikipedia.org/wiki/Pumped-storage_hydroelectricity

Solar PV vs Solar Thermal/CSP Comparison: What They Are, Differences, & Examples

Solar PV vs Solar Thermal/CSP Comparison: What They Are, Differences, & Examples

This is a comparison guide on Solar PV (photovoltaic) vs Solar Thermal (CSP – Concentrating Solar Power) Energy.

We look at what each of these types of solar technology are, their differences, and examples of each in terms of solar projects and operational solar farms worldwide.

 

Summary – Solar PV vs Solar Thermal/CSP

  • Solar PV (used for electricity) and Solar CSP (used for electricity, or heating water) are different solar technologies
  • Each can be used on a large utility scale (big solar farms with hundreds or thousands of panels that produce electricity for utilities), or on a distributed residential scale (for individual households, buildings and locations)
  • Solar PV (photovoltaic) currently leads Solar Thermal/CSP by a very wide margin in terms of annual investment of money, annual and total installed capacity, electricity generation, and electricity consumption
  • This trend (of PV outpacing CSP) is only expected to continue into the future with continued investment in and expansion of Solar PV projects
  • Despite Solar PV’s popularity, Solar CSP has a few small advantages (dispatchability, and generating electricity while the sun is down) over Solar PV

 

What Is Solar PV

  • A solar panel made up of solar cells that converts sun light energy into electricity

– vivintsolar.com

 

Solar PV can be utility scale (solar farms), or distributed (usually rooftop installations and other standalone solar cells that help stabilise or support a power system in the event of power disruptions, blackouts etc.).

 

How Solar PV Works

  • Sunlight (light photons) hits the solar cells on a solar panel
  • The solar cells convert sunlight into DC electricity
  • DC electricity is fed to the inverter (might be a string inverter or a microinverter) that turns DC energy into AC electricity
  • This AC electricity can be used directly or stored in a battery for later use

– vivintsolar.com

 

What Is Solar Thermal/CSP

  • The use of the Sun’s thermal energy to generate electricity or heat water
  • There’s several different types of Solar Thermal plants such as Linear Fresnel, Tower, Dish and Trough (cleanenergycouncil.org.au)

 

How Solar Thermal/CSP Works

  • Solar CSP uses mirrors (lenses and reflectors) to capture the Sun’s thermal energy (infrared radiation) to heat a (thermodynamic) liquid or an oil, create steam, drive a heat engine/generator, and generate electricity
  • Solar CSP can also be used for heating and desalinating water

– wikipedia.org, sciencedirect.com, cleanenergycouncil.org.au and irena.org

 

Global Installed Capacity, Production & Consumption Of Solar Energy

Worldwide, solar energy installed capacity, production and consumption stats are:

  • At the end of 2018, solar as a whole made up 20% of installed capacity for renewables
  • At the end of 2018, solar PV made up 2.4% of total global electricity production
  • At the end of 2016, solar was the third most consumed renewable energy source for electricity

– bettermeetsreality.com

 

  • Between 2012 to 2018, solar PV led all renewables in annual additional installed capacity by a wide margin (55% alone in 2018), followed by wind energy, hydropower, and all other renewables as a group behind that (including solar CSP/thermal)
  • Solar thermal/CSP made up 0.4% of total global electricity production in 2018 along with other renewables like geothermal and ocean power

– vox.com

 

  • In 2017, solar PV and solar thermal were both responsible for 4% each of renewable energy consumption worldwide

– iea.org

 

Solar PV vs Solar CSP Installed Capacity

  • In 2018, global Solar PV installed capacity was 480,357 MW, and Solar CSP was 5,469 MW

– irena.org

 

Solar PV vs Solar CSP Electricity Generation

  • In 2016, Solar PV electricity generation was 317,613 GWh, and Solar CSP was 11,037 GWh

– irena.org

 

Solar PV vs Solar Thermal – Differences, Cost, Efficiency & More

Solar PV and Solar Thermal are both used on the large utility scale, and on the smaller distributed/individual scale. Cost, efficiency, and other variables can differ depending on the scale they are used.

 

Apart from the obvious differences of investment, installed capacity, electricity generation and electricity consumption, and how they actually work (light energy vs heat energy), some of the key differences at the utility/large scale are:

 

  • [solar CSP] provides a dispatchable energy supply – that is, their power output can be adjusted based on grid demand. This makes them more flexible than traditional solar PV plants.

– cleanenergycouncil.org.au

 

  • One of the main advantages of a CSP power plant over a solar PV power plant is that it can be equipped with molten salts in which heat can be stored, allowing electricity to be generated after the sun has set.

– irena.org

 

Overall, CSP on the utility scale probably faces more barriers and challenges than Solar PV which is far more widely used.

 

On a household and individual level, greenmatch.co.uk mentions some of the cost, efficiency, flexibility and other differences between the two technologies at https://www.greenmatch.co.uk/blog/2015/04/solar-panels-vs-solar-thermal

For example, solar thermal is usually used for heating water on homes, whereas panels might be used for electricity.

 

Investment In Solar Energy

In 2016, solar and wind energy by far had the most investment money on a global level compared to other renewable energy sources.

 

Future Of Solar Energy (Solar PV & Solar CSP)

  • By 2023, solar PV is expected to grow to 8% of renewable energy consumption worldwide, whilst solar thermal is expected to stay the same at 4%

– iea.org

 

  • [there is expected to be] a 46% growth over the period 2018 to 2023 in renewable energy as a whole … with solar PV accounting for more than half of this expansion [and, supportive government policies and market improvements are some of the main causes]
  • Utility-scale projects represent 55% of this growth
  • China alone accounts for almost 45% of global solar PV expansion
  • CSP is expected to grow 87% (4.3 GW) over the forecast period, 32% more than in 2012‑17
  • [some of the barriers facing CSP expansion individually are] technology risk, restricted access to financing, long project lead-times, and market designs that do not value storage continue to challenge CSP deployment

– iea.org

 

Examples Of Solar PV & Solar Thermal Worldwide – Largest Solar Farms, & Countries With The Most Solar PV & Solar CSP

You can view lists of the largest solar PV and solar thermal power stations at:

  • https://en.wikipedia.org/wiki/List_of_photovoltaic_power_stations
  • https://en.wikipedia.org/wiki/List_of_solar_thermal_power_stations

 

Countries with the highest installed capacity:

  • In 2018, China, Europe, the US, Japan and Germany had the highest installed capacities of Solar PV in MW.
  • In 2016, Spain and the US easily had the highest installed capacities of Solar CSP in MW.

– wikipedia.org

 

Sources

1. https://www.bettermeetsreality.com/installed-capacity-production-consumption-of-renewable-energy-worldwide-by-country-by-source/

2. https://www.bettermeetsreality.com/countries-that-invest-the-most-in-renewable-energy-what-they-invest-in/

3. https://www.bettermeetsreality.com/the-different-types-of-renewable-energy-sources-with-examples/

4. https://en.wikipedia.org/wiki/Solar_power_by_country

5. https://www.sciencedirect.com/topics/engineering/solar-thermal

6. https://www.vox.com/energy-and-environment/2019/6/18/18681591/renewable-energy-china-solar-pv-jobs

7. https://www.iea.org/renewables2018/

8. https://www.iea.org/renewables2018/power/

9. https://www.irena.org/solar

10. https://www.vivintsolar.com/learning-center/how-does-solar-power-work

11. https://www.cleanenergycouncil.org.au/resources/technologies/solar-thermal

12. https://en.wikipedia.org/wiki/List_of_photovoltaic_power_stations

13. https://en.wikipedia.org/wiki/List_of_solar_thermal_power_stations

14. https://www.greenmatch.co.uk/blog/2015/04/solar-panels-vs-solar-thermal

15. https://www.iea.org/newsroom/news/2018/october/modern-bioenergy-leads-the-growth-of-all-renewables-to-2023-according-to-latest-.html

Onshore vs Offshore Wind Energy Comparison: What They Are, Differences, & Examples

Onshore vs Offshore Wind Energy Comparison: What They Are, Differences, & Examples

This is a comparison guide of onshore vs offshore wind energy.

We look at what each one is, their differences and examples of current large wind projects globally.

 

Summary – Onshore vs Offshore Wind Energy

  • Wind energy involves the use of the wind to turn wind turbine blades, which in turn generates electricity via a generator
  • Onshore wind energy far outpaces offshore wind energy in installed capacity and electricity production/generation, but, offshore wind energy is still looked at as having good long term potential for growth
  • Offshore wind energy has traditionally been more expensive, but is becoming more price competitive recently (especially in Europe). Offshore wind energy usually has higher wind speeds available.
  • Wind energy in general has a strong future due to projected growth across a number of areas over the coming years

 

How Wind Energy Works

Wind energy is pretty simple in theory:

  • Kinetic energy from wind hits a wind turbine’s blades and turns that energy into rotational energy
  • The blades are connected to a shaft in the turbine, and this shaft is connected to a generator
  • The generator creates electrical energy through electromagnetism

– irena.org

 

Onshore vs Offshore Wind Energy – What They Are

Onshore wind energy is land based wind turbines and wind farms.

Offshore wind energy is wind turbines located in seawater or freshwater sources.

A better explanation of offshore wind energy might be:

  • Offshore wind energy is the use of wind farms constructed in bodies of water, usually in the ocean on the continental shelf, to harvest wind energy to generate electricity. 
  • … [it] includes inshore water areas such as lakes, fjords and sheltered coastal areas, utilizing traditional fixed-bottom wind turbine technologies, as well as deeper-water areas utilizing floating wind turbines

– wikipedia.org

 

Onshore vs Offshore Wind Energy – Differences, Costs, Power, Efficiency Etc.

Apart from the obvious location based difference between the two (land vs water based), there are additional differences between onshore and offshore wind.

Offshore wind energy has traditionally been more expensive, and higher wind speeds are usually available offshore (leading to better efficiency per capacity installed).

 

  • The cost of offshore wind power has historically been higher than that of onshore wind generation, but costs have been decreasing rapidly in recent years and in Europe has been price-competitive with conventional power sources since 2017
  • Higher wind speeds are available offshore compared to on land, so offshore wind power’s electricity generation is higher per amount of capacity installed … [and] opposition to construction is usually much weaker

– wikipedia.org

 

Wind speed can be a key variable, because:

  • Theoretically, when wind speed doubles, wind power potential increases by a factor of eight.
  • The amount of power that can be harvested from wind depends on the size of the turbine and the length of its blades. The output is proportional to the dimensions of the rotor and to the cube of the wind speed

– irena.org

 

Global Installed Capacity, Production & Consumption Of Wind Energy

Worldwide, wind energy installed capacity, production and consumption stats are:

  • At the end of 2018, made up 24% of installed capacity for renewables
  • At the end of 2018, made up 5.5% of total global electricity production
  • At the end of 2016, was the second most consumed renewable energy source for electricity

– bettermeetsreality.com

 

  • Between 2012 to 2018, solar PV led all renewables in annual additional installed capacity by a wide margin, followed by wind energy, hydropower, and all other renewables as a group behind that (including solar CSP/thermal)

– vox.com

 

  • … in 2016 wind energy accounted for 16% of the electricity generated by renewables

– irena.org

 

Onshore vs Offshore Wind Energy Electricity Generation Globally

In 2016:

  • Onshore wind energy was responsible for 916,313 GWh of electricity generation
  • Offshore wind energy was responsible for 41,596 GWh of electricity generation

Onshore wind energy has far exceeded offshore wind energy electricity generation, even stretching back to 2010.

But, offshore wind energy offers big potential.

– irena.org

 

Investment In Wind Energy

In 2016, solar and wind energy by far had the most investment money on a global level compared to other renewable energy sources.

 

Future Growth Of Wind Energy

Wind energy is expected to continue growing strongly in the future.

 

  • Wind energy is expected to grow from 9% of total renewable energy consumption in 2017, to 12% of renewable energy consumption in 2023.

– iea.org

 

  • Wind capacity is forecast to grow by 324 GW and reach 839 GW by 2023, with offshore wind accounting for 10% of the increase
  • Offshore wind capacity is expected to almost triple to nearly 52 GW in 2023, with half the growth driven by the European Union and the other half by China and other Asian countries
  • Onshore wind capacity growth could be 25% higher globally, increasing annual additions to over 60 GW over the forecast period

– iea.org

 

Examples Onshore & Offshore Wind Energy Worldwide – Largest Wind Farms, Countries With The Largest Wind Farms

You can view lists at:

  • https://en.wikipedia.org/wiki/List_of_onshore_wind_farms
  • https://en.wikipedia.org/wiki/List_of_offshore_wind_farms

China, the US and India have some of the largest current onshore wind farms.

Europe (UK and Germany, amongst others countries) and Asia (China mainly) have some of the largest current offshore wind farms.

 

Sources

1. https://www.bettermeetsreality.com/installed-capacity-production-consumption-of-renewable-energy-worldwide-by-country-by-source/

2. https://www.bettermeetsreality.com/countries-that-invest-the-most-in-renewable-energy-what-they-invest-in/

3. https://www.bettermeetsreality.com/the-different-types-of-renewable-energy-sources-with-examples/

4. https://www.vox.com/energy-and-environment/2019/6/18/18681591/renewable-energy-china-solar-pv-jobs

5. https://www.iea.org/renewables2018/

6. https://www.iea.org/wei2018/ (includes figures for auction amounts of onshore and offshore wind)

7. https://www.irena.org/wind

8. https://en.wikipedia.org/wiki/List_of_onshore_wind_farms

9. https://en.wikipedia.org/wiki/Offshore_wind_power

10. https://en.wikipedia.org/wiki/List_of_offshore_wind_farms

11. https://www.iea.org/renewables2018/power/

What Is The Future Of Renewable Energy?

What Is The Future Of Renewable Energy?

The aim of this guide is to get an objective idea of what the future of renewable energy might look like.

To do this, we look at some of the current trends to do with renewable energy, and look at how they might develop going forward.

 

Summary – What Is The Future Of Renewable Energy

  • The amount of renewable energy being used for electricity worldwide has significantly increased over the last few decades
  • Hydropower currently provides the most electricity of any renewable energy source
  • The next logical sectors to progress into (in terms of energy generation from renewables) over the medium to long term after the power/electricity sector are, transport, and heating and cooling, which are primarily fossil fuel driven at the moment
  • Investment in renewables has increased over the last decade – with solar and wind receiving majority of global investment money
  • The number of cities sourcing an increasing amount of their electricity from renewables has grown over the past decade (e.g. As of January 2018, 42 cities were getting at least 100% of their electricity from renewable energy sources, 59 cities were at at least 70%, and 22 cities at at least 50%)
  • There’s also roughly 12 countries at the moment that are sourcing over 90% of their electricity from renewables
  • Looking at these stats, and as long as investment and government support is strong, it’s expected renewable energy use will keep on growing, especially as the cost for renewables becomes more competitive compared to fossil fuels (due to economies of scale, increased demand, fossil fuels becoming more expensive with new environmental regulations and requirements for eco friendly fossil fuel plants, and so on)
  • There are many cities and countries with renewable energy targets for the future (i.e. by the years 2025, 2030, 2040 and 2050)
  • China is currently the world leader in both renewable energy generation and consumption, and renewable energy investment. But, China is also the world leader in coal use
  • There are a number of factors that can impact how quickly a country or city will look to transition to an energy mix with an increasing share of renewables and reduced fossil fuels. Each town, city, region, country (especially developed vs developing countries) has different factors, variables and scenarios they face with a transition. Some places (like the MidWest and California in the US for example) are pushing harder for renewables than others
  • There are a number of studies and published reports that indicate we can run on renewables (either in majority in an energy mix, or in full) either globally or on a country by country basis, with solar, wind and hydro (pumped hydro energy storage energy) being some of the major suggested renewable energy sources
  • There are challenges with transitioning to renewables, such as the issues faced by Germany and China (like variability, not having an power grid, not having adequate transmission lines, upfront costs, and more)
  • There are many potential benefits as well though, including addressing greenhouse gas emissions and climate change, reducing air pollution, creation of jobs, addressing scarcity of fossil fuel resources, energy independence, reducing the impact of mining and other environmental issues, and more

 

Below are some relevant guides that provide more insight on where we may potentially be heading with the use of renewable energy sources in the future for both electricity, and the overall energy needs of our societies:

 

Current Energy & Electricity Mixes Of Some Of The Major Countries In The World

 

Installed Capacity, Production & Consumption Of Renewable Energy Worldwide

 

Countries & Cities That Use The Most Renewable Energy

 

Countries That Invest The Most In Renewable Energy

 

Future Of Energy In China

 

Future Of Energy In The United States

 

Can Renewables Replace Fossil Fuels, Meet Demand, & Power The World?

 

Other Resources On Renewable Energy

 

Sources

1. Various BMR guides

Can Renewable Energy Replace Fossil Fuels, Meet Demand, & Power The World? (Moving Towards 100% Renewable Energy)

Can Renewable Energy Replace Fossil Fuels, Meet Demand, & Power The World? (Moving Towards 100% Renewable Energy)

We know that renewable energy is already being used in many places across the world.

But, can renewable energy replace fossil fuels, meet demand, and power the world?

Could we eventually see a world run 100% on renewable energy?

These are the questions we have to answer and summarise in this guide.

 

Summary – Can Renewable Energy Replace Fossil Fuels, Meet Demand, & Power The World?

  • Energy is required across many sectors in society
  • At the moment, renewable energy has made the biggest impact in electricity generation and consumption, with hydropower accounting for majority of the impact 
  • The transport, and heating and cooling sectors are still primarily run on fossil fuels (but in the future, there will likely be more progress made to electrify these sectors with renewable energy sources in the energy mix) 
  • Some major countries in the world like China and India still use fossil fuel heavy energy mixes, but China in particular is also the world leader in renewable energy investment
  • What we do know though, is that, as of 2018, there are at least 42 cities getting 100% of their electricity from renewable energy, with many more up around the 50% and 70% benchmarks
  • What we also know, is that, there are at least 12 countries getting 90%+ of their electricity from renewable energy
  • So, we know that it’s possible for cities, countries and regions to get majority of their electricity from renewable energy sources over fossil fuels
  • Some of these countries and cities have faced challenges and problems of varying sizes in their transition to increasing shares of renewable energy. The issues a country like Germany has faced in their transition have been well documented. Studying cities, States and countries that have already begun their transition to greater use of renewables and learning from them can help other places not make the same mistakes, and ensure a better transition with better planning and implementation
  • There are 100’s of studies and forecasts that have been published that explore the feasibility of 100% renewable energy and increasing shares of renewable energy for power worldwide, and for specific countries. Each of these studies list the benefits and challenges in transitioning to a higher share of renewable energy, and suggest different energy mixes for different regions and countries, but several summarise that there are less economic and technological barriers to increasing renewable energy share, and more political, social and cultural barriers
  • Pairing the examples of cities and countries already run on majority renewable energy with the positive studies and forecasts for increasing renewable energy in our electricity and overall energy mix worldwide, and it looks like a reality that renewables could majority or entirely take over from fossil fuels in the mid to long term future if social, cultural and political agenda leans that way
  • Solar, wind, and hydropower (to be able to store and supply energy when wind and solar aren’t producing) are suggested as the main renewable energy sources in some of the main studies and forecasts, but some also suggest energy mixes with geothermal, wave, tidal, bioenergy, and even natural gas or hydrogen
  • Overall, the factors and variables influencing the uptake of increased renewable energy share to replace fossil fuels is different in each region, town, city and country as a whole. Each one needs an individual assessment and short and long term strategy. The development and breakthroughs in new technology are a big variable too
  • The pros and cons of renewable energy have to be weighed against the pros and cons of fossil fuels in both the short and long term across social, environmental, economic and other areas. 
  • In slower transitions, it’s possible fossil fuels could compliment renewable energy in an energy mix until energy infrastructure and energy systems can fully support renewables
  • Nuclear is a forgotten energy source that fits somewhere in between fossil fuels and renewables, and could be utilised in some places. Some sources also indicate that coal fired CCS (carbon capture storage, or use) technology and some other forms of improved or hybrid fossil fuel technology could play a part in some energy mixes
  • Climate change/global warming and greenhouse gas emissions, air pollution from air contaminants (and the associated human health problems and mortality rates), an increase in the human global population (leading to increased demand for energy), growth of developing countries (leading to increased generation and consumption of energy), and the finite nature of fossil fuel resources are some of the biggest issues to consider that are related to the energy sector
  • When pursuing increased use of renewable energy sources, we might ask how effectively we are addressing each of the problems we are trying to solve (like reduced greenhouse gas emissions, peak oil, reduced air pollution), and what trade offs we are making by not pursuing the use of another energy source like fossil fuels. This can help keep an energy strategy and plan more objective as opposed to political or subjective
  • Although there are some that say that renewables are too costly and unreliable, there are others that point to the significant environmental and social costs of fossil fuels, as well as the current investment and subsidies fossil fuels have been afforded, and point out that renewables can only get better in the future with new technological breakthroughs (their potential might be a lot higher than fossil fuels). Others point out that some of the problems pointed out with renewables, apply to fossil fuels and nuclear too
  • Ultimately, a transition to 100% renewable energy systems worldwide will require a balancing of various social, economic, environmental, and other types of priorities and factors. It will involve possible breakthroughs in aspects like energy storage and back up dispatchable energy sources. And, while it’s clear there are problems like variability/intermittency of renewable energy, it’s also clear that it’s likely solutions to the current problems of renewable energy can be developed in the future. In any transition, a hybrid flexible energy system that composes of different types of energy (fossil fuels, nuclear, conventional renewables, and modern renewables) might be required as a bridging system 

 

Can Renewable Energy Replace Fossil Fuels?

Each city or country has it’s own energy mix i.e. the energy sources that provide overall energy or electricity for that city or country, and the proportions in which they provide that energy or electricity.

Some countries have an energy mix that is composed of mostly fossil fuels, whilst others have an electricity energy mix that is composed mostly of renewable energy sources.

An example of a country with majority fossil fuel energy sources is China (China is currently the world leader in coal consumption), while a country like Iceland gets 100% of it’s electricity from renewable energy sources.

So, yes, renewables can replace fossil fuels in a country or city’s energy mix in differing proportional amounts (could be anywhere from 0 to 100%).

What is important to note though is that energy is different to electricity. Electricity is a sector in itself, whilst energy stretches across various sectors – transport for example is a sector that is primarily powered by fossil fuels (although this will slowly change with more electric vehicles on the road in the future powered by renewable energy sources).

So, right now, renewable energy sources have penetrated into electricity production and consumption, but have not penetrated heavily into the transport and heating and cooling sectors – which are still both primarily fed by fossil fuels.

 

Can Renewable Energy Meet Demand?

Demand is the amount of energy or electricity required by all sectors and industries within a city or country.

Demand for energy might be classified in three categories – base load (the minimum amount of energy required to meet demand 24/7), intermediate and peak demand.

Some sources debate this, but traditionally, renewables have been a variable source of energy. Solar and wind for example provide a lot of energy when the sun shines and when winds are blowing, but that energy can drop significantly when the sun and wind drops off.

A few different approaches to address variability are:

  • Huge batteries to store solar and wind energy (as was done in South Australia). But, batteries tend to only be able to store enough energy for short term output (a few hours), and with currently technology, they are very costly the bigger they get and the more storage they have
  • Having fossil fuel or nuclear backups power plants that can ramp up quickly when solar and wind drops off
  • Having pumped hydro power with water storage (and energy storage) that can ramp up quickly when solar and wind drops off. Strategies for the future might involve using renewable solar and wind energy to power pumping water uphill to make pumped hydro completely or mostly clean energy

In Germany, variability and mismatching of the timing of energy supply and consumption, has caused a few issues such as overloading power grids, excess energy forcing utilities to have to pay customers to take excess power, and other issues.

Complimentary energy sources (in addition to wind and solar) can also help provide more power for peak energy demand periods as well.

 

Can Renewable Energy Power The Entire World?

This is perhaps too broad of a question.

Studies done on this question indicate they can, and that there are only political, social and cultural barriers, and not technological or economic.

Perhaps instead of asking if renewables can power the entire world, we look to ask if renewables can power individual towns, regions, cities and countries.

Every location has different factors and variables at play that will determine what the answer in the short, medium and long-term looks like to this question.

Also, developing countries are going to face starkly different factors and variables to developed countries.

 

Moving Towards 100% Renewable Energy …

100% renewable energy may be a goal for a city or country for electricity, or for all the major energy consuming sectors (such as transport, heating and cooling, commercial/industrial, agriculture etc.).

Some cities and countries already have a large amount of electricity sourced from renewable energy sources.

Other cities and countries have committed to certain targets to have a greater % of their electricity comes from renewables at different stages up until the year 2050.

It’s possible the transition (however slow or fast that might happen) to a greater majority of renewables in the energy mix may involve fossil fuels and nuclear as complimentary energy sources for different reasons.

Different sources point out the drawbacks of renewable energy, but, other sources point out that the drawbacks to renewable energy are nowhere near as destructive or harmful as fossil fuels in the mid to long term.

Greenhouse gas emissions and climate change, outdoor air pollution, resource depletion, and energy efficiency are some of the main issues that can be addressed in different ways by moving towards 100% RE (or majority renewable energy) in an energy or electricity supply.

 

Potential Challenges, Issues & Considerations With Moving Towards Increased Renewable Energy

Potential challenges, issues and considerations in moving towards renewable energy may include:

Challenges

  • Solar and wind can be variable sources of energy i.e. they only provide energy when the sun is shining and the wind is blowing
  • Matching the timing of variable energy generation with consumption of this energy (energy needs to be consumed when it is produced unless it gets stored), and what to do in the event a power grid is overloaded 
  • Some sources think that the challenges are not technological or economics related, but rather political, institutional, cultural/social
  • Whether or not renewables can scale up fast enough by a certain year/target time, and whether fossil fuels and nuclear energy are required in the meantime
  • Adding turbines to existing hydropower dams (when using hydro power as a backup source for solar and wind) may not physically be possible. And, discharging hydro power in some ways described by some studies and reports on future expansion of renewable energy can put unacceptable impacts on aquatic ecosystems and downstream water users
  • Upgrading and changing existing power grids to accommodate renewable energy can be expensive
  • Large scale storage batteries for renewable energy (like solar and wind) can be expensive
  • Building new transmission power lines and interconnectors to accommodate renewables can be expensive and take a lot of time
  • A divided public and government on climate change as an issue (i.e. lack of awareness of what it is, and how important it may or may not be to address with renewable energy)
  • Lobbying by groups, such as fossil fuel groups, who have a vested interest in existing energy systems, to argue only against renewables (without presenting the benefits)
  • Solar and wind farms can be land intensive compared to nuclear and fossil fuels (forbes.com) – i.e. more land is needed for the same amount of power
  • Renewables can have negative environmental and wildlife consequences e.g. wind farms can be in the way of migratory bird flight paths in some countries and regions (forbes.com)
  • Poorer countries and States might not be able to afford the sometimes more expensive upfront cost of renewables
  • Current technologies [in some US States] are intermittent, variable, and unpredictable as they depend on the weather and consequently have limited capacity factors. At the scale needed, storage is currently not a viable option as the technology is very expensive and still developing (renewableenergyworld.com)
  • Supply and demand have to be equivalent in the power market at any given time [so, making a decision of what energy source to take offline when a new renewable energy source is added can be difficult]. Also, in the short-run and in emergency situations, the grid regulators have to shut off the connection to the grid from the renewable energy sources … and this makes it more difficult for investors to recover the costs of their systems, and it also raises transmission costs for everyone else (renewableenergyworld.com)
  • Baseload power sources (coal, natural gas, and nuclear) require time to ramp up and down and thus are relatively less responsive to changes in demand … [and, this time taken to ramp up and down can be expensive] (renewableenergyworld.com)
  • Over time, operating at lower scales [for energy sources that are decreased or reduced when renewables are added] raises costs for utilities (and later the ratepayers) as they now have to operate the power plants at scales that are inefficient (renewableenergyworld.com)
  • Another issue with the large targets for renewable energy is that they create load uncertainty for nuclear power plant operators [and, as renewables become cheaper, it may lead to the shut down of nuclear plants as they may not be able to compete] (renewableenergyworld.com)
  • [When renewables are supported by government portfolio standards instead of natural market demand, subsidies might be increased in value, and this increase might be passed onto electricity ratepayers if there is no cost control in place] (renewableenergyworld.com)
  • [A shortage of strategic metals (nickel, cobalt, copper, lithium) could be a problem in the future for batteries and other renewable energy technology]
  • Barriers to electricity infrastructure like transmission lines could prevent an increase in grid capacity for renewables (renewableenergyworld.com)
  •  … diluteness, proximity, and reliability can be three [barriers to renewable energy] (lifepowered.org)
  • [Power density and how much land wind and solar need compared to fossil fuels and nuclear can be an issue – wind and solar comparatively need a lot of land for the same power – especially the big wind and solar farms. Some domestic areas can install their own solar panels] (lifepowered.org)
  • [… areas where renewables are installed are usually nowhere near where energy is needed – transmission lines can be costly and slow to build … Texas has already spent billions of dollars on thousands of miles of transmission lines that transport electricity from wind and solar farms in West Texas to cities in East Texas.] (lifepowered.org)
  • [The last issue with wind and solar is reliability/dispatchability – dispatchable generators need to be able to ramp up and down to help match elec supply with demand (and wind and solar struggle because it isn’t always windy or sunny). To supplement this – large batteries are needed for energy storage, and they can be costly] (lifepowered.org)
  • [energy grids in fossil fuel dominated places are designed on the basis of large controllable generators … and, has little energy storage. Intermittent renewable energy present a problem in this instance. However, technological advancements are presenting solutions to intermittence, such as new hybrid solar panels that can harness energy from raindrops and therefore be effective during day and night] (greenwoodsolutions.com.au)
  • … geographical distribution and variability and uncertainty in output pose challenges to the US’ electricity system with renewables (nrel.gov)
  • The Reneweconomy.com.au case study from the CSIRO referenced below lists some of the technical challenges in moving towards 100% renewables such as flexibility of the energy grid in dealing with variable energy, dispatch ability of energy sources to complement renewables, need for energy storage, the need for frequency control and the provision of inertia, price signaling and communication between distributors and the wholesale electricity market, and deciding on base load from either fossil fuels, nuclear or other renewables
  • [Some of the challenges in increasing the penetration of renewables in all sectors are electricity transmission (the way electricity is transmitted, generated and sold) … The electricity system need to be flexible to deal with variable output, and market structures need to evolve to integrate renewable power properly] (swecourbaninsight.com)
  • … political ideology and the capture of governments by powerful vested interests is a major barrier [to renewable energy growth] (reneweconomy.com.au)
  • [market designs favor fossil fuels, market failure favors fossil fuels and fossil fuels want to cling to their traditional business models] (reneweconomy.com.au)
  • Older power engineers are attached to the concepts of base load, intermediate and peak load power stations … and cannot envisage a system that contains a large fraction of variable RElec and where demand can be modified almost instantaneously (reneweconomy.com.au)
  • [Intermittency and variability, overcapacity, grid stability, variable electricity prices, back up dispatchable power sources, and energy storage are some of the biggest challenges facing a transition to renewable energy] (power-technology.com)
  • [Intermittency and variability of renewable energy means that power supply is lacking when there is less wind and sunshine, and there can be a surplus (overcapacity) supply of power when there is lots of sunshine and wind] (power-technology.com)
  • [Overcapacity is when there is an over supply of renewable energy – usually caused by the variable/intermittent nature of wind and solar. Overcapacity can overload power grids, and can lead to variable electricity prices] (power-technology.com)
  • [Grid stability can be impacted when there is an overcapacity of RE – examples of this are Poland and the Czech Republic’s power grids, which receive transmitted electricity from Germany’s power system] (power-technology.com)
  • [Variable electricity prices can be a result of the introduction of renewable energy. RE can make the price of electricity more competitive. But, RE can also create problems with pricing of electricity when there is a surplus, due to variability. Power plants might actually have to pay commercial customers to take their electricity in times of surplus. This can create uncertainty and problems for all types of energy generation – as prices aren’t predictable and stable] (power-technology.com)
  • [The variable nature of renewable energy means that back up energy sources, known as dispatchable energy sources, might be needed. These sources might need to be able to ramp up and down quickly to fill in energy gaps when renewable energy supply is down, and not overload the grid when renewable energy supply is up. Back up energy sources are usually coal or natural gas. Nuclear can also figure into this equation. Using natural gas or coal as backup energy sources can actually increase greenhouse gas emissions in the short term, as seen in Germany, and actually goes against short term carbon emission targets. Furthermore, if sufficient back up energy sources aren’t in place for some energy systems, this can lead to blackouts – as seen in South Australia] (power-technology.com)
  • [Renewable energy use, along with how competitive natural gas and coal can be without carbon pricing, can mean the closure of nuclear plants – especially if not supported by the government] (power-technology.com)
  • [Increasing installed capacity of solar and wind can have a negative impact on land use and the transformation of landscape in some countries – as solar and wind farms aren’t as land efficient as fossil fuel power plants] (power-technology.com)
  • [Capital and upfront costs, siting and transmission, market entry, an unequal playing field for different energy sources and competitors, and reliability misconceptions can be some of the challenges for renewable energy technology in general, and when it comes to expansion and increased use] (ucsusa.org) 

 

Other Considerations

  • The final energy mix a country or city uses i.e. how much of each renewable source, how much of each fossil fuel source, how much nuclear, and so on
  • Whether or not more debatable energy sources like nuclear, bioenergy, hybrid energy sources and hydrogen, and CSS fossil fuels are used in addition to modern renewables like solar, wind, hydro, geothermal and wave/tidal
  • Energy storage – whether batteries, or pumped hydro energy storage is used to store energy when variable energy sources like solar and wind are used. Other options are flexible natural gas power plants, or, adding turbines to more rapidly convert stored heat from solar thermal power plants into electricity.
  • The number of hours of energy storage available e.g. 2 hours, 12 hours, 24 hours, or more
  • The natural renewable resources each country has available e.g. Iceland’s renewable energy resources to draw from might be different to Australia (Australia is abundant in land, sun and win for example)
  • Level of financial investment in renewables (can vary from year to year, and with support from government mechanisms)
  • How much a government supports and commits to renewables, and the policies, subsidies and other incentives they introduce (subsidies on fossil fuel energy and renewable energy, subsidies for residential solar installation, carbon taxes etc.)
  • Certainty for businesses and investors in the market – they need to know (have some certainty) they can get a return and profit on investment over 20 or 30 years
  • How cheap each renewable source is to provide electricity
  • Whether or not renewable energy installations degrade grid reliability by undermining continuously operated “baseload” nuclear and coal power plants in countries like the US (spectrum.ieee.org)
  • Whether baseload power is necessary to a well-functioning electric grid or not. Some say baseload (such as fossil fuels and nuclear power) isn’t necessary, but rather a flexible and dynamic power supply from both variable and energy storage renewables will suffice. An example of this is when California utility PG&E announced plans to shut down a nuclear plant as they said this baseload plant was ill suited to help manage the California power grid which has a diverse mix of energy sources and renewables  (spectrum.ieee.org)
  • What happens to existing fossil fuel and nuclear equipment and infrastructure, and these industries as a while, when they are phased out – some future scenarios see them remodelling to supply hydrogen or synthetic gas (instead of real natural gas)
  • How fast (at what rate per year) fossil fuel is phased out
  • What happens to jobs in each industry with phase outs – are new jobs created, and are existing workers re-trained and re-skilled to work in new industries?
  • [Economically in the future, we will need large investments in grid storage, transmission to distribute power and to smooth out the issues of intermittency] (greenwoodsolutions.com.au)
  • [Politically, creation of the regulatory framework, setting standards and offering incentives to economies to make a significant shift in their energy usage to renewables will be required for increased use of renewables] (greenwoodsolutions.com.au)
  • Growth in renewable energy can be influenced by … strong lobby groups looking to support national industry … [and] National industry is in turn more likely to have grown where there are natural resources to support the early development of an industry (swecourbaninsight.com)
  • Public interest and acceptance for particular types of renewable energy are driven by multiple factors, including support of local jobs and industry, visual impacts and public awareness of climate change (swecourbaninsight.com)
  • [It’s possible there might be an] inadequate understanding of the engineering, scientific and quantitative modelling has found its way through to the political mainstream (reneweconomy.com.au)

 

IEA.org outlines some of the individual factors that might impact expansion of individual renewable energy sources globally into the future:

General

  • Market and policy framework developments (whether there are supportive government policies and market improvements)
  • Regulatory and financial challenges

Solar PV

  • Cost reductions of solar PV technology impact on technology competitiveness
  • Presence of feed in tariffs and deployment quotas

Solar CSP

  • Multilateral bank support
  • Cost reduction potential 
  • Technology risk
  • Access to financing
  • Project lead times
  • Market designs
  • Whether or not energy storage is valued 

Wind

  • Federal tax incentives
  • Presence of feed in tariffs
  • Grid integration challenges
  • Faster commissioning of transmission lines
  • Larger auction volumes (more auction activity and faster auction implementation)
  • Faster commissioning of planned projects

Hydro

  • The development of large scale hydro
  • Concerns of social and environmental impact
  • Untapped resource potential
  • Attractive economics to improve electricity access affordably
  • Completing feasibility studies, securing finance, finishing civil works
  • Full commissioning of mega projects

Geothermal

  • Demand in developing countries and emerging economies
  • Abundant resource availability
  • Support of projects by government policy
  • Pre development risks, and securing financing for projects

Marine

  • Whether a renewable technology is in the large scale stage, or small-scale demonstration and pilot project stage (like marine renewable technology is)

 

Renewableenergyworld.com writes about some practical tips for moving towards 100% renewables:

  • Make sure the choices of consumers in green energy are privatised
  • Consider incentives or updating portfolios and adding a nuclear energy tier, to keep nuclear power in operation in the short term [as premature shutdowns and switching to natural gas may actually increase GHG emissions]
  • Keep investing in emerging energy technology
  • Keep updating existing energy policies
  • Find more ways to make CSS and direct capture technologies more economically feasible
  • Focus on energy efficiency in the future which can help increase capacity for renewables and provide ancillary services to the grid
  • In addition to the power sector, figure out how to decarbonize the transportation, manufacturing, and agriculture industries
  • Spread low carbon energy to developing economies

 

The environmental impacts of wind, solar and hydro energy are listed at https://interestingengineering.com/is-mark-jacobsons-plan-to-use-100-renewable-energy-feasible

 

Additionally, we’ve written some guides which outline some of the other challenges in moving to renewables (generally, and for specific countries like China)

 

Benefits Of Using Increased Renewable Energy 

Potential benefits of moving to renewables over fossil fuels may include:

  • Addressing greenhouse gas emissions and climate change/global warming
  • Addressing outdoor air pollution, air quality, and the associated human health problems and mortality rate associated with it
  • Addressing future potential issues with scarcity of fossil fuel resources
  • Reduction of fossil fuel resources mining (and associated problems with mining)
  • Economic benefits like job creation, economic stimulus, additional income streams for individuals, and so on
  • Reduce costs and money spent addressing some of the other problems mentioned in this list
  • Addressing other environmental issues that happen directly or indirectly as a result of the above problems, like water pollution, land degradation, acid rain, ocean warming and acidification etc. 
  • Providing energy independence to countries who currently rely on importing fossil fuels from other countries
  • Renewable technology and equipment is only expected to get cheaper and better/more advanced in the future – leading to potentially only more favorable future outcomes
  • Renewable energy can compete with fossil fuels for cheaper wholesale electricity prices
  • Renewable energy can be brought to previously energy poor areas and address energy poverty (especially in places that are still using biofuels for indoor cooking and heating and suffer from indoor air pollution)
  • Save on other critical resources like water which is heavily used on fossil fuel plants for cooling (ucsusa.org)
  • Energy efficiency and and overall reduction in total energy use (by switching to renewables over fossil fuels)

 

You can read more about the potential benefits of using a greater share of renewables for energy and electricity in this guide:

 

Studies & Reports That Assess The Feasibility Of 100% Renewable Energy Scenarios Globally, & For Different Countries

There are various studies and reports that assess the feasibility of moving towards greater shares of renewable energy in the future, either globally, or in individual countries.

They may also list pathways of how we can get there, and what the energy mix would look like.

We’ve listed and summarised them below:

 

Wikipedia.org: (renewable energy globally, and in a range of individual countries)

  • According to a review of the 181 peer-reviewed papers on 100% renewable energy which were published until 2018, “[the] great majority of all publications highlights the technical feasibility and economic viability of 100% Renewable Energy systems
  • Mark Z Jacobsen says that ‘producing all new energy with wind power, solar power, and hydropower by 2030 is feasible, and that existing energy supply arrangements could be replaced by 2050’
  • A 2012 study by the University of Delaware for a 72 GW system considered 28 billion combinations of renewable energy and storage and found the most cost-effective, for the PJM Interconnection, would use 17 GW of solar, 68 GW of offshore wind, and 115 GW of onshore wind, although at times as much as three times the demand would be provided. 0.1% of the time would require generation from other sources
  • The barriers to large scale renewable energy are: climate change denial, the fossil fuels lobby, political inaction, unsustainable energy consumption, outdated energy infrastructure, and financial constraints
  • [Overall, when considering 100% renewable energy scenarios] Because the wind blows during stormy conditions when the sun does not shine and the sun often shines on calm days with little wind, combining wind and solar can go a long way toward meeting demand, especially when geothermal provides a steady base and hydroelectric can be called on to fill in the gaps
  • In countries with high variation in energy demand by season (for example the UK uses far more gas for heating in the winter than it uses electricity) but lacking hydropower electrical interconnectors to countries with lots of hydropower (e.g. UK – Norway) will probably be insufficient and development of a hydrogen economy will likely be needed: this is being trialled in the UK and 8 TWh of inter-seasonal hydrogen energy storage has been proposed.
  • In Australia, as well as storing renewable energy as hydrogen, it is also proposed to be exported in the form of ammonia.

 

Interestingengineering.com (renewable energy globally):

  • A new Jacobson paper outlined that …
  • 139 countries can be broken down to 20 regions and the most appropriate energy storage resolution individually suited to those regions can be implemented.
  • … [first though] stability of the grid [needs to be found out] every 30 seconds in 5 years, in each region
  • 100% renewables has risk and demands a significant amount of efforts

 

Ucsusa.org: (renewable energy in the US):

  • … the U.S. can generate most of its electricity from renewable energy by 2050
  • … an 80 percent renewables future is feasible with currently available technologies, including wind turbines, solar photovoltaics, concentrating solar power, biopower, geothermal, and hydropower
  • … [a high renewable scenario can] meet electricity demand across the country every hour of every day, year-round.
  • Variable resources such as wind and solar power can provide up to about half of U.S. electricity, with the remaining 30 percent from other renewable sources.
  • [there are] multiple pathways to reach this goal
  • [to reach this goal] the right long term clean energy policies are needed, the electricity grid needs to be improved, there needs to be more advanced grid planning, there needs to be prices on carbon emissions, and there needs to be increases in funding for research and development of renewables

 

Nrel.gov (renewable energy in the US):

  • A Renewable Electricity Futures Study (RE Futures) concludes that ‘renewable electricity generation… in combination with a more flexible electric system, is more than adequate to supply 80% of total U.S. electricity generation in 2050 while meeting electricity demand on an hourly basis in every region of the country’
  • [This can happen via a] portfolio of supply- and demand-side options, including flexible conventional generation, grid storage, new transmission, more responsive loads, and changes in power system operations
  • The abundance and diversity of U.S. renewable energy resources can support multiple combinations of renewable technologies
  • [some benefits would be decreased GHG emissions and decreased water use]

– nrel.gov

 

Reneweconomy.com.au (renewable energy in Australia):

  • [the CSIRO says] there is no apparent technical impediment to reaching 100 per cent renewables for the [Aus] national electricity grid
  • … introducing renewables at a share of 10, 20 or 30 per cent is fairly trivial on the basis that the existing generation capacity has a lot of flexibility to deal with the variability
  • … existing back-up and redundancy for the current coal-dominated grid [is] already in place
  • … peaking gas, using the dispatchability of coal and the interconnection between states allow renewables to contribute to the system. That has generally been the approach in most states
  • [in South Australia, and in renewable modelling, problems can begin to occur at around 40% renewable energy share. To deal with this, you either have to add energy storage, or a dispatchable form of energy that can support renewables. Dispatchable energy could be other renewables like solar thermal or geothermal, or another form of dispatchable energy]
  • [for 100% renewable penetration into the electricity system … we might need] very, very high battery deployment to achieve that … and also technologies like biogas, which is dispatchable, and dispatchable biomass. This take care of energy balancing on a half-hour basis. There are also other issues around the need for frequency control and so forth, where you need additional technologies that provide inertia. That could include things like synchronous condensers and more advanced inverters for the battery technologies, and so forth.]
  • [it should be noted that deploying high renewable energy penetration solutions and having them work in reality can be different to simulation and modelling]
  • [price signalling and communication between technologies down at the distribution end of the market and up into the wholesale market … could be useful in the future]
  • [base load is not essential with fossil fuels if you have an energy mix of wind and solar PV, and pumped hydro storage]

 

Iflscience.com: (renewable energy in the US)

  • [when running every major energy sector on renewable energy] across all 50 states, [there was a] 39 percent reduction in total end-use power demand by the year 2050
  • About 6 percentage points of that is gained through efficiency improvements to infrastructure, but the bulk is the result of replacing current sources and uses of combustion energy with electricity
  • … clear plan[s] [have been laid out] for each state to make an 80% transition to renewable energy by 2030, and reach 100% by 2050
  • Some States will have a much more achievable plan than others
  • Initial costs will be high, but would eventually average out to roughly the current cost of fossil fuel infrastructure

 

TheConversation.com (renewable energy for the world):

  • The world can limit global warming to 1.5℃ and move to 100% renewable energy [by 2050] … without relying on technological fixes such as carbon capture and storage …
  • the gas industry can be a transition fuel … without its infrastructure becoming obsolete once natural gas is phased out
  • [there can be a] conversion of the gas industry to synthetic fuels and hydrogen over the coming decades … Natural gas will be increasingly replaced by hydrogen and/or renewable methane produced by solar power and wind turbines. While most scenarios rely on batteries and pumped hydro as main storage technologies, these renewable forms of gas can also play a significant role in the energy mix.
  • [there can be an increase in the] amount of economic output per unit of energy use
  • [there’s a relatively slow phase out of natural gas in this scenario]
  • [different types of jobs in the energy sector are impacted differently with the above scenario]

 

Stanford.edu (renewable energy for each State of America):

  • … a 50-state roadmap has been developed for transforming the United States from dependence on fossil fuels to 100 percent renewable energy by 2050
  • [it is designed to] maximize the renewable resource potential of each of the 50 states

 

TheGuardian.com: (renewable energy in the US)

  • This study considered only wind and solar
  • Wind, solar, and storage could meet 90–100% of America’s electricity needs [based on 36 years of hourly weather data, and the US’ electrical demand and variation over this time]
  • Wind and solar are variable – they fluctuate in space and time with their supply of energy
  • Fluctuation of these energy sources can complement each other though – solar power generation is highest in the summer and lowest in the winter. Wind power is greatest in the spring and fall. Wind turbines work at night when solar panels are dormant 
  • There were two future scenarios the authors of this study focussed on … 
  • 1. … with 100% power capacity and no mechanism to store energy, a wind-heavy portfolio is best (about 75% wind, 25% solar) and using large aggregate regions is optimal. It is possible to supply about 75-80% of US electrical needs.
  • 2. If the system were designed with excess capacity (the 150% case), the US could meet about 90% of its needs with wind and solar power.
  • … both systems could generate too much power for use. In this event, excess energy could be stored in several ways, for example in batteries or by pumping water into elevated tanks and then letting the water fall at night and turn a turbine.
  • When the above study was modified to allow up to 12 hours of US energy storage … They then found that the 100% capacity system fared even better (about 90% of the country’s energy) and the optimal balance was now more solar (approximately 70% solar and 30% wind). For the over-capacity system, the authors found that virtually all the country’s power needs could be met with wind, solar, and storage.
  • Furthermore, people are learning to use energy more wisely, either by using more efficient products or purchasing electricity during off-peak hours. These behavioral changes can also help us reach a 100% clean energy target.

 

Cnet.com: (renewable energy in Australia, and the US)

  • … simulated up to six years using real data on sun and wind and electricity demand, and in [a] peer-reviewed paper [have] shown [Australia] could have operated the national electricity market if [it had] installed enough [infrastructure] entirely on renewable energy with the same reliability as the same existing system
  • [there’s not technical challenges in this transition, but political challenges … for example, some politicians might have too close of a relationship with fossil fuel industries, or, a government may simply not show enough commitment to renewables and this can cause uncertainty for investors]
  • [the renewable energy setup would include wind, solar PV, high voltage transmission lines, pumped hydro and energy storage batteries]
  • [the US has more than enough resources to run entirely on renewables as well]
  • [challenges for a transition to renewables are mostly political, institutional, cultural]

 

Spectrum.ieee.org (renewable energy globally, and in the US):

  • [Mark Jacobsen, a Stanford University engineer, says the world can be run on solar, wind and hydro energy by mid century]
  • Critics of Jacobsen’s journal publication debate it citing invalid modeling tools, modeling errors, and “implausible and inadequately supported assumptions
  • Jacobsen’s evaluation of a renewable future does not include fossil fuels with CSS technology, or nuclear reactors
  • [Critics say that a new generation of nuclear reactors are required because renewables] cannot scale up fast enough
  • [Jacobson’s model for the US] replaces fossil fuels for heating and transportation with hydrogen and electricity generated by renewables]
  • Jacobsen’s model for the US implies a [15-fold expansion in hydropower generating capacity] as he uses hydro power for a backup to wind and solar.
  • Critics point out that Jacobsen’s approach of adding turbines to existing hydropower dams is not physically possible
  • Critics point out discharging hydro power from dams in some ways described can put unacceptable impacts on aquatic ecosystems and downstream water users
  • Critics point out that invalidating Jacobsen’s hydropower approach means blackouts and a breakdown of the system
  • But, Jacobsen says his hydropower upgrade proposals have technical and economic viability, and ‘reflect a cost that policymakers pursuing his road map would need to consider’
  • All clean energy proposals will always have trade offs compared to existing fossil fuel set-ups
  • Jacobson also has alternative sources of backup power, such as adding turbines to more rapidly convert stored heat from solar thermal power plants into electricity
  • Battery storage is yet another option, but is deemed unnecessarily costly
  • [other studies apart from Jacobsen’s have relied mostly on flexible natural gas power plants rather than dams or batteries to handle residual power demand]
  • Some say renewables may degrade the US’ power grid reliability
  • Some say base load power is necessary to a well-functioning electric grid – whilst other say flexibility is required, not base load power plants

 

Further Resources On A Future With Increased Use Of Renewable Energy 

Below are some resources that contain different information relevant to a future with increased use of renewable energy. We’ve summarised (paraphrased) each:

 

Renewableenergyworld.com:

  • Renewable Energy Portfolio Standards require the utilities to generate or procure a minimal percentage of energy in their portfolios from renewables energy
  • [favorable technical potentials in a State can lead to more of a particular renewable energy being established]

 

Lifepowered.org:

  • … policies, such as renewable energy subsidies and mandates and extra taxes on fossil fuels [can be economically devastating]

 

Iflscience.com:

  • each region or State in a country has current energy demands, and these energy demands might change over time 
  • energy use [might be divided] into four sectors: residential, commercial, industrial and transportation

 

Wikipedia.org:

  • As of 2019, however, [renewable energy] needs to grow six times faster to limit global warming to 2 °C (3.6 °F)
  • [After the power sector, the transport and heating and cooling sectors could be next to be electrified by renewable energy sources]

 

Cnet.com:

  • Outlines reasons why some countries aren’t using renewables
  • Every country has different natural renewable resources and potential available – for example, Iceland gets it’s electricity from hydro power and geothermal sources. Australia, on the other hand, is a country rich in large scale solar and wind potential because of the amount of land it has (so much so, that there is potential to export solar energy to Asia in the future). Texas has one of the biggest capacities for wind in the US
  • How much a government commits to renewables can determine their uptake in a State or country
  • Hydropower has traditionally been cheapest way to source renewable electricity, but solar and wind are starting to outpace and become cheaper than hydro economically
  • Solar panels can either be installed on buildings and feed energy into a battery, or they can be set up in solar farms and feed directly into the grid
  • Government incentive in Germany encouraged much more solar installation than in a country like Australia
  • Batteries to store wind and solar energy can be expensive if you need one for more than a day’s worth of energy (South Australia recently installed one as an example) – they are good for short term bursts of power, like for example an energy peak demand period which might last 2 or 3 hours
  • Solar and wind can be variable sources of energy i.e. energy is produced more when there is wind and sunlight, but less when there isn’t
  • Two of the main sources of hydro energy are hydroelectric plants, and pumped storage hydro energy
  • Pumped storage hydro energy is a cheaper way of storing renewable energy than using batteries
  • Pumped storage hydro energy could be used as a backup to solar and wind energy (seeing as though solar and wind are variable)
  • It’s possible South Australia could have prevented their last blackout if they had pumped hydro storage energy to compliment their current renewable energy sources
  • Successful use of hydro can maintain electricity during times of drought

 

Sciencealert.com:

  • Outlines the potential that pumped storage hydro energy has for the future to provide enough stored energy to power the world
  • Thousands of new pumped storage hydro energy sites have been found worldwide via an algorithm
  • These sites still have to pass on-site inspections and tests (there’s several factors that need to be checked off for a site to be suitable), but if only 1% of them pass final assessment, they will have adequate storage capacity for the world
  • The big positive that pumped storage hydro energy offers is that it can store energy. Solar and wind energy don’t have this ability
  • In the future, we might see pumped storage hydro energy sites that use wind and solar energy to pump water up to the top water reservoir – providing almost a completely clean form of energy 

 

  • apart from the electricity sector, there are the heat and transport sectors which could become renewable powered. Right now, transport, through the use of petrol and diesel-fuelled cars; and for heating, through the use of oil and natural gas boilers in buildings [are fossil fuel powered]
  • [we could switch to bio fuel or electric and hybrid cars]
  • [we could switch to district heating or electrification of heat]
  • [Although each country has different renewable energy resources … this difference is thought to be smaller than those relating to fossil fuel reserves]
  • [It’s expected as renewables become cheaper, subsidies will drop away – which is good, and brings the market back into play for pricing, as opposed to regulation controlling pricing]
  • [One of the biggest challenges in the future with renewables is matching timing of energy supply with demand]
  • Digitalisation, energy storage and demand response are the keys to helping future energy systems maintain balance
  • The generation of energy for heat, electricity and transport is interconnected through storage, monitored through smart meters, and changed through voluntary shifting of demand

– swecourbaninsight.com

 

  • [Several types of renewable energy can provide baseload power such as] … geothermal energy is available at all times, concentrated solar thermal energy has storage capability, and wind energy can be stored in compressed air
  • It will be over a decade before we can produce sufficient intermittent renewable energy to require high levels of storage, and there are several promising energy storage technologies

– skepticalscience.com

 

  • [The fact that carbon isn’t priced in some countries allows coal to beat out nuclear and other energy sources]
  • [Some people say that renewables aren’t reliable enough to provide baseload energy because of their intermittency, whilst others say renewables can provide a flexible and dispatchable grid, and can be designed for reliability, security and affordability]
  • … several of the [renewable energy] simulation studies achieve reliability with zero or negligible base-load capacity
  • … for a reliable generating system [it is unnecessary for renewable power stations to be dispatchable
  • [Increased demand for energy in the future doesn’t take into account the increased] energy efficiency renewables can provide … [or the facts that] a unit of electricity from wind and solar uses three times less energy to produce than fossil fuels, and EVs half as much as internal combustion engines
  • The capacity factors of different energy sources matter in calculations and models
  • [100% renewable electricity supply system are possible even if] RElec is limited to technologies that are commercially available now. Regions with insufficient local RE resources will in future be able to import RE via transmission line and/or tanker carrying renewable fuels

– reneweconomy.com.au

 

  • [Even though a country or city might have an average % of it’s electricity provided by renewable energy sources, on some days that are very sunny and breezy, that % can significantly increase. For example, Germany had an average at the end of 2017 of around 36%, but on very sunny and breezy days, that number can jump up as high as 86%. On those days, coal plants and nuclear plants may either not be in use, or severely reduced in use.]
  • [Intermittency and variability, overcapacity, grid stability, volatile electricity prices, back up dispatchable power sources, and available energy storage are some of the problems that face increased use of renewable energy]
  • [Intermittence and variability is the nature of how consistent the energy supply is from renewables i.e. whether the sun and wind are consistent and how consistent the resulting energy supply is to the grid]
  • [Overcapacity is when a power grid gets flooded with surplus/excess energy – usually caused by very sunny and highly windy conditions]
  • [Grid stability is a grid’s ability to deal with excess power being pushed through it, and the result of that extra power i.e. are there blackouts and shutdowns, or is there a non destructive way that excess energy is dealt with and used such as filtering off to the power grids of other States and countries who need it]
  • [Volatile energy prices can be a result of overcapacity – when there is too much electricity – it pushes prices down … sometimes in the negative. Volatile prices not only reduce profits, but increase uncertainty for investors and energy suppliers]
  • [Backup energy sources that are dispatchable are needed when renewable energy is highly variable and there is inadequate forms of energy storage in place. These dispatchable energy sources like coal and natural gas need to be able to ramp up and down quickly when more power is needed, or when power needs to be reduced quickly]
  • [Energy storage can be important in a renewable energy system. If there is stored energy, then this energy can be used in the event that there is lower renewable energy being supplied due to poor wind and sun conditions]
  • [Some regulations, like those in Germany, require renewable energy to be used first in the grid, so fossil fuel energy is pushed out of the grid and used by neighboring countries when there is an excess of renewable energy. Countries like Poland and Czech Republic have suffered overloaded power grids as a result of variable energy from Germany]
  • [Germany energy suppliers have also experienced volatile electricity prices, which have sometimes gone in the negative, as a result of overcapacity and variability. This means power plants have to pay commercial customers to take their electricity]
  • [Volatile electricity prices] can be somewhat addressed by replacing the feed-in tariff subsidy with a market-responsive auction system based on pre-set RES capacity growth caps
  • [In Germany, because of a lack of Government support for nuclear, natural gas and coal power are usually the back up sources of power for variable renewable energy sources. This has led to a short term increase in greenhouse gas emissions]
  • [Because of intermittency, even in a given year when solar and wind installed capacity increases, poor wind and sun conditions can lead to an overall drop in solar and wind energy generation]
  • [Intermittency and overcapacity, without adequate back up energy sources, or without proper energy storage, can lead to blackouts]
  • [South Australia is an example of a place that has experienced blackouts as a result of renewable energy and a lack of adequate energy back up … although they have now got a giant energy storage battery installed]
  • [California is an example of a State that has experienced issues with intermittency and overcapacity of renewable energy]
  • [Some estimates of what Germany would need to do to go 100% renewable, is build a hugely expansive solar and wind system compared to what they have now, and also invest in a significant energy storage system compared to what they have now … so there are costs to expansion]. This could cause a host of problems related to overcapacity, energy spot prices and carbon-intensive back-up power when RES output falls, not to mention the landscape impact of wind turbine installation on this scale and the resistance this might cause. [Also, in this scenario] … If the back up power sources are replacing expensive gas fuel by cheap lignite – then GHGs will increase 
  • [Increased production by intermittent renewable energy sources may not be the way to go as there would also be huge tradeoffs on land use and how landscape is transformed with solar and wind farms that take up far more land than fossil fuel power plants. Wind converters and transmission lines also take up a lot of land. For these reasons and others …] countries might look at other forms of CO2 free energy production
  • [Ultimately, a transition to renewables isn’t going to be without challenges] … It requires balancing environmental efficiency, energy security and harmonious electricity markets is a complex task that will take many decades to solve
  • [An approach that falls somewhere between supporting existing energy systems and new renewable energy systems might be required]
  • Nuclear power could play an important role in providing low-carbon baseload or back-up power, although its suitability for dispatchable capacity is limited by how slowly nuclear plants can ramp up or down on demand when compared to gas turbines. Public and political appetite for significant nuclear fleet expansion is also low in many countries, with Germany proving particularly nuclear-averse.
  • [A strategy that provides solutions and components in moving towards increased use of renewables might involve] back-up dispatchable power, demand response and energy efficiency measures, distributed generation, data-driven smart technologies, grid-level energy storage and more integrated networks. The EU, through its harmonised policy environment, has an opportunity to take the lead on common energy markets and interconnected grids, although technical, political and financial obstacles to this are currently formidable
  • … If you want to use fluctuating renewable power, you have to upgrade the grids across Europe
  • Given the extended timespan of the challenge [of moving towards 100% renewables], breakthrough power sources such as fusion energy – which could provide emissions-free baseload power in virtually unlimited amounts – could emerge as well. Large-scale energy storage is still in the early stages of development with several competing technologies; the efficiency of dispatchable storage will be a concern moving forward, but breakthroughs in this area could also have a decisive effect on the feasibility of greater RES predominance.
  • While it’s undeniable that RES intermittency and overcapacity are significant problems for the energy systems of today, a host of options can be developed to create solutions for the energy systems of tomorrow. But until fully clean energy systems become technologically and economically feasible, some level of hybridism will be needed to offset the variability of intermittent renewables

– power-technology.com

 

  • [some of the barriers and challenges for renewable energy technology are …]
  • [Capital Costs – such as the upfront of building solar and wind farms compared to fossil fuel plants. Higher costs can lead to less investment by investors in some places. Over time though, costs can average out, and renewables seem to be getting cheaper and more affordable over time too. It’s also worth noting that new coal and natural gas plants that have to meet environmental regulations are becoming increasingly expensive as they have to have certain systems and devices fitted to decrease emissions and pollution]
  • [Decentralization, Siting and Transmission – fossil fuels are centralized generally to one spot, where as renewables like solar and wind can be decentralized i.e. spread out providing energy from many locations … solar for example can come from utility solar farms, or from distributed solar panels on buildings and in residential locations. Siting renewable energy that is decentralized can present issues with] negotiations, contracts, permits, and community relations, all of which can increase costs and delay or kill projects … [Transmission can also be an issue as power lines, interconnectors, power grids, and other infrastructure are required or need to be upgraded in order to get energy] from where it is to where it needs to be. [Areas that have the best renewable energy expansion potential for large solar and wind farms might be located far away from where the power is actually needed, which might be in cities for example … and it might be very difficult and expensive to build new infrastructure to service this expansion]
  • [Market Entry – fossil fuels are well established and developed industries with] existing infrastructure, expertise, and policy. [Renewable energy sources are less established and developed, and it can be harder for renewable sources in general, and individual renewable competitors to take a foot hold] Increased government investment in clean energy—in the form of subsidies, loan assistance, and research and development—would help
  • [Unequal Playing Field – fossil fuels might have political support, as well as subsidies, tax breaks and other incentives and loop holes available that renewables don’t have. It’s also possible investment and support for fossil fuels in the past could have went to renewables or energy efficiency instead. Fossil fuels, unless forced to have new environmentally friendly systems that minimize emissions and pollution, don’t pay the full environmental and social cost of their operation] Emission fees or caps on total pollution, potentially with tradable emission permits, are examples of ways we could use to help remove this barrier
  • [Reliability Misconceptions – such as pointing out that RE is variable and needs the support of other energy sources to meet base load requirements. But, renewables can be more predictable] when spread across a large enough geographic area—and paired with complementary generation sources. Modern grid technologies like advanced batteries, real-time pricing, and smart appliances can also help solar and wind be essential elements of a well-performing grid. Tests performed in California … a place with high renewable energy use … shows real-world validation for the idea that solar and wind can actually enhance grid reliability. Many utilities, though, still don’t consider the full value of wind, solar, and other renewable sources. Energy planners often consider narrow cost parameters, and miss the big-picture, long-term opportunities that renewables offer. [So, there needs to be more awareness around this and a willingness to go beyond these misconceptions]

– ucsusa.org

 

Sources

1. https://www.bettermeetsreality.com/countries-cities-that-get-most-of-their-electricity-from-renewable-energy-sources/

2. https://www.bettermeetsreality.com/energy-sources-energy-mix-by-country-where-major-countries-in-the-world-get-their-energy-from/

3. https://www.bettermeetsreality.com/countries-that-invest-the-most-in-renewable-energy-what-they-invest-in/

4. https://www.bettermeetsreality.com/installed-capacity-production-consumption-of-renewable-energy-worldwide-by-country-by-source/

5. https://www.sciencealert.com/scientists-spot-530-000-potential-pumped-hydro-sites-to-meet-all-our-renewable-energy-needs

6. https://www.cnet.com/news/if-renewable-energy-can-power-entire-countries-why-isnt-everyone-doing-it/

7. https://spectrum.ieee.org/energywise/energy/renewables/can-the-us-grid-work-with-100-renewables

8. https://www.bettermeetsreality.com/renewable-energy-vs-fossil-fuels-vs-nuclear-comparison-guide/

9. https://www.bettermeetsreality.com/economic-impact-benefits-of-renewable-energy-clean-energy/

10. https://www.bettermeetsreality.com/pros-cons-of-renewable-alternative-energy-now-into-the-future/

11. https://www.theguardian.com/environment/climate-consensus-97-per-cent/2018/mar/26/study-wind-and-solar-can-power-most-of-the-united-states

12. https://en.wikipedia.org/wiki/100%25_renewable_energy

13. https://news.stanford.edu/news/2014/february/fifty-states-renewables-022414.html

14. https://www.iflscience.com/environment/here-s-roundmap-get-us-run-100-renewable-energy-2050/

15. https://www.ucsusa.org/clean_energy/smart-energy-solutions/increase-renewables/renewable-energy-80-percent-us-electricity.html

16. https://www.forbes.com/sites/michaelshellenberger/2019/05/06/the-reason-renewables-cant-power-modern-civilization-is-because-they-were-never-meant-to/#47301a3aea2b

17. https://theconversation.com/heres-how-a-100-renewable-energy-future-can-create-jobs-and-even-save-the-gas-industry-110285

18. https://www.iea.org/renewables2018/power/

19. https://www.bettermeetsreality.com/reasons-why-we-dont-use-more-renewable-energy-worldwide-barriers-obstacles-challenges-in-switching-over-to-renewables/

20. https://www.bettermeetsreality.com/the-challenges-with-chinas-transition-from-coal-to-natural-gas-renewable-energy/

21. https://www.bettermeetsreality.com/considerations-when-choosing-different-energy-sources-in-the-future-social-environmental-economic-practical-more/

22. https://www.renewableenergyworld.com/ugc/articles/2019/04/02/why-100-renewable-energy-goals-are-not-practical-policies.html

23. https://lifepowered.org/challenges-for-100-renewable-energy/

24. https://www.greenwoodsolutions.com.au/news-posts/a-100-renewable-energy-future-whats-the-reality

25. https://www.ucsusa.org/clean-energy/renewable-energy/barriers-to-renewable-energy

26. https://reneweconomy.com.au/the-fake-arguments-against-100-renewable-energy-65406/

27. https://www.power-technology.com/features/featureovercapacity-and-the-challenges-of-going-100-renewable-5872868/

28. https://interestingengineering.com/is-mark-jacobsons-plan-to-use-100-renewable-energy-feasible

29. https://www.swecourbaninsight.com/urban-energy/the-limits-to-renewable-energy/

30. https://skepticalscience.com/renewable-energy-baseload-power.htm

31. https://www.nrel.gov/analysis/re-futures.html

32. https://reneweconomy.com.au/csiro-says-australia-can-get-100-per-cent-renewable-energy-86624/