There’s been a lot of investment in renewable and green type energy sources over the last decade or so.
In addition to that, the amount of electricity we produce globally from renewables has gradually been increasing.
With these things in mind, we thought we’d put a quick guide together outlining which renewable or green energy source might be the ‘best’.
This is obviously a subjective thing, so to give the answer some objectivity, we’ve assessed ‘best’ by comparing energy sources across various factors.
Summary – Which Renewable Or Green Energy Source Is The ‘Best’?
- Renewable energy sources generally include solar, wind, hydropower, geothermal, wave, tidal, and bioenergy/biomass/biofuel
- If we add green energy sources to the mix, nuclear energy can be included too
- Although nuclear energy has many pros including great power density/energy output and essentially emission and pollution free operation, the mining required for uranium and radioactive waste produced as a waste product does means that it probably loses points overall as a green energy compared to some renewables (there’s also the impact of nuclear waste management to think about)
- Hydropower currently provides around 50% of the electricity provided globally by renewables
- Over the last 10 years or so, solar and wind have by far received the most investment money
- Solar (PV) and wind (mainly onshore) appear to be the ‘best’ renewable and green forms of energy going forward into the future (although, you could add hydropower to the list as well based on the current picture of renewable energy installed capacity, production and consumption). They are relatively affordable energy sources in terms of cost per unit of electricity produced, that can be set up to provide electricity at decent scale, and also have good resource to electricity conversion efficiency. They aren’t perfect though – they do usually need a complimentary energy source (usually a fossil fuel like coal or natural gas, or even nuclear) to help meet baseload power demand, and sometimes to meet peak load demand. So, the ‘best’ energy source or sources may still be supported by another less ideal energy source in the overall energy mix for logistical reasons
- The ‘best’ energy source can also be country and even city or region specific – different countries, cities and regions have different challenges, logistics and natural resources to consider in setting up the best short and long term energy mix for them. So, this should be taken into account to provide a city, state/province and country level solution/answer.
- A good understanding of the pros and cons of renewable energy in general, as well as the different renewable energy sources helps is coming up for an energy solution for each city, state or province, or country
Below, we summarise the leading energy sources by the following aspects:
- Cost per unit of electricity produced for investors and energy suppliers
- Wholesale price of electricity for consumers
- How dangerous and safe each energy source is towards humans
- Impact on environment and wildlife
- Capability based on installed capacity, production and consumption
- Investment and what that means for the future
- Number of jobs provided
- Practical and logistical considerations
- Country, city and region based considerations
*Note – whilst one energy source might be more eco friendly and environmentally sustainable across various factors than another energy source, it might lack some of the technical and practical advantages of other energy sources. Just as one example, nuclear doesn’t suffer from the same variability or power output issues solar and wind might.
Cost Per Unit Of Electricity Produced
Cost per unit of electricity produced can be measured among a few factors, such as capital costs, and the levelized cost of electricity which tries to capture the lifecycle costs that contribute to making a unit of electricity.
What we see is a changing picture when it comes to cost.
Fossil fuels used to be cheaper across many measures (because old plants didn’t have to have pollutant or emissions controls or systems), but increasing controls and regulations for fossil fuel plants to meet emissions and pollution requirements is lifting the cost of fossil fuels, and economies of scale and advancements in technology are reducing the price of renewables. Subsidies can also play a role here.
By the 2020’s, it is expected renewables will be cheaper than fossil fuels per unit of electricity produced.
As far as capital costs go for renewables, offshore wind and advanced nuclear tend to be expensive. Solar PV and onshore wind tend to be cheaper and affordable.
As far as LCOE, onshore wind and solar PV are expected to be very cheap in some countries by the early 2020’s.
Wholesale Price Of Electricity
Wholesale price of electricity for consumers can differ between countries, and between states/provinces and regions within a country.
It depends on factors like local energy mix, government policies and local energy suppliers.
How Dangerous Is Each Energy Source To Humans?
When looking at health problems caused by outdoor air pollution from the burning of energy sources, carbon dioxide emissions from power plants and energy operations, and accidents in the energy sector – nuclear, solar, wind and hydropower are among the safest energy sources compared to fossil fuels.
Impact On Environment & Wildlife
Nuclear requires mining of uranium, which has a range of potential environmental problems such as land degradation, water pollution, air pollution, and destruction of ecosystems and wildlife habitats (among other issues).
Each renewable energy source has both a carbon footprint, and water footprint to consider throughout the entire lifecycle of the energy process.
Renewables can have several issues to do with the environment – the building of dams and storage areas for hydropower degrades rivers and water sources, solar farms can take up a lot of land space (and introduce industrial issues to remote areas), wind farms that are set up off-shore can displace reefs, seabeds and aquatic habitats.
Renewables can have several issues to do with wildlife – wind generators can cause problems for flying animals, hydropower for marine life and aquatic species, bioenergy can cause land clearing and a range of agricultural related issues if grown as crops.
But overall, renewables tend to be more eco and animal friendly because of they tend not to have emissions, air pollutants or waste products when in operation.
Solar equipment also has to be either recycled or dumped to landfill once it reaches the end of it’s lifespan, and the materials used to make solar panels, wind generators, dams etc. still might have to be mined or require a raw production process that uses a lot of energy. Solar panels even include plastic in them – and plastic comes from petroleum as one ingredient.
Read more about eco and wildlife impact of energy sources in these guides:
- Impact Of Energy & Electricity Production On The Environment
- Impact Of Energy & Electricity On Animals & Wildlife
- Carbon Footprint Of Each Energy Source
- Water Footprint Of Each Energy Source
Capability Based On Installed Capacity, Production & Consumption
Hydropower leads installed capacity, production and consumption across many measures, comprising of around 50% of total renewable end user consumer electricity.
But, solar and wind follow behind hydropower across many measures too.
- When accounting for all factors, it’s likely that renewable energy results in more jobs per dollar invested than fossil fuels
- … [one report found that] wind and solar photovoltaic investments lead to at least 40% more jobs per dollar than coal
Practical & Logistical Considerations
Practical and logistical considerations of the energy sources are location and technology specific.
They centre around things like budgets/funding, investing and profitability/return on investment, energy independence, subsidies, exports and imports, abundance of natural and renewable resources, variability, dispatchability, power density, the existing power grid, infrastructure like transmission lines, ability to meet low demand, baseload power and peak demand, as well as considerations for not just electricity, but the heating and cooling and transport sectors (for electric vehicles for example). These are just some practical considerations and logistics – there are many more.
Solar and wind tend to be variable power sources that need another energy source like a fossil fuel or nuclear to help meet base load and sometimes peak energy demand.
Hydropower is pretty flexible, but it’s long term generation capacity and potential can be limited.
Nuclear tends to be far more expensive in some Western countries than some Asian countries, and is therefore is priced out as a power source in these countries.
These are just examples of some of the logical and practical considerations for different energy sources.
Country, City & Region Based Considerations
Each country, city and region will have different considerations in choosing their final short term and long term energy mix.
Country wide trends can differ to city, and region specific trends.
Also consider that ‘cities use a higher percentage of renewable electricity than countries. Already, there are at least 100 cities around the world using between 90 and 100 percent renewable electricity’. Cities can often better implement and test renewable energy sources compared to countries where nationwide uptake can be very slow and cumbersome for various reasons.
China as a whole faces an interesting situation whereby they are the leaders in renewable energy investment, installed capacity, production and consumption across many measures, but they also face existing issues in transitioning away from coal energy in the short to medium term (because of factors like investment in existing coal plants, and a power grid and infrastructure set up for fossil fuels)