As part of assessing the best energy sources for the future, we are looking at the pros and cons of these different energy sources.
This is our guide on the Pros & Cons Of Coal Energy.
Summary – Coal Energy Pros & Cons
- Cost effective and provides an affordable electricity source in some places
- Some coal supply estimates are as high as hundreds of years (based on current known resources)
- Power supply infrastructure in many cities is currently set up for fossil fuels
- Not a variable power source like solar or wind for example
- Has good power density/power per unit (black coal in particular)
- Technology like CSS can capture air contaminants and emissions from coal
- Coal can be converted into different types of fuel
- Coal plants are sometimes cheaper than gas or nuclear plants
- Currently provides significant jobs and income in major countries like China
- Has provided economic growth in the past for developed countries
- Can help countries have better energy independence from other countries e.g. they might become less dependent on natural gas from Russia
- Some estimates of air pollution from coal burning aren’t as high as what is usually reported
- Some estimates of mercury emissions aren’t as high as what is usually reported
- Coal waste by products can be used for other applications
- Although cheap on it’s own, coal is heavily subsidised in some countries (which helps keep coal prices competitive)
- Not a green form of energy > produces greenhouse gas emissions when burning
- Is finite as a resource – not a renewable form of energy
- Contributes to outdoor air pollution via the release of various air toxins (and contributes to human health conditions and mortality rates)
- Can release/emit mercury
- Toxins released from coal can be poorly monitored in some regions of the world
- Air pollution from coal can be very costly to the health system (and can contribute to health conditions like lung cancer and cardiovascular disease)
- Air pollution from burning of coal can contribute to acid rain
- Coal supplies at plants need to be topped up, unlike some renewable forms of energy
- Coal mining can be very destructive environmentally and to local communities
- Coal burning can produce radiation
- Clean coal right now isn’t actually ‘clean’
- Carbon capture technology has it’s flaws, and adds to the cost of coal energy and electricity
- ‘Clean coal’ technology research and development has cost a lot of money over the last few decades
- Brown coal is an inefficient form of energy
- Brown coal can be uneconomic to transport long distances
- Some ‘Clean Coal’ technology isn’t always effective
- Coal waste like coal ash can build up, and even pollute the environment (it can also be costly to treat and manage coal waste properly)
- Thermal coal power plants can use a lot of water for cooling
- Some argue that coal power plant licenses that don’t regulate emissions allow investors and plant operators a ‘free pass’ to pollute the environment
Coal is cheap, widely available, has infrastructure already in place (for power grids for many cities around the world), and has adequate resources/supplies still left.
It essentially offers a lot of affordable power supply.
However, the carbon dioxide and air toxins it emits during combustion is a huge problem, and mining creates damage and harmful effects (although new more eco friendly coal plants have been designed and constructed in recent years)
Because of climate change and air pollution, countries like China are trying to transition to other forms of energy like natural gas, and renewables such as solar and wind.
Coal may offer several major economic and social benefits right now, and major economies may depend on it, but transitioning to cleaner and less destructive energy sources as soon as feasibly possible seems like a smart strategy.
*Note – the above pros and cons are broad generalisations. Obviously there are different variables to each specific energy project that impact the final pros and cons (like new technology that reduces emissions for coal power plants just as one of many examples). Each energy project and situation (in different countries and cities) should be analysed individually. Having said that, some broad principles and patterns about the pros and cons of different energy sources tend to stay consistent too.
What Is Coal Energy
Coal energy or coal power refers to the combustion of a fossil fuel called coal for heat generation that is used to spin a turbine to produce electricity.
Coal is a combustible sedimentary rock having a black or brownish-black color, which can be found in rock strata (layers of sedimentary rock, soil or igneous rock that was formed at the surface of the planet), in veins also called coal seams or layers of underground rock called coal beds.
Coal consists of mostly carbon along with other elements such as hydrogen, nitrogen, sulfur and oxygen.
Coal Energy Pros
- Cost Effective/Can Provide A Cheap Form Of Electricity – usually one of the cheaper forms of energy because of how widely available it is (amongst other factors). Brown coal in particular can be cheap, as well as provide jobs, and support the local economy. When you take subsidies out of the equations, brown coal energy in some places in the world can be about $30 per MWh compared to solar at about $70-$80 per MWh.
- Some Estimates Indicate A Good Supply Left – The current stockpiles of coal can provide the world with more than a century of energy, while US-based coal reserves could last over 400 years. Beyond the stockpiles of coal that have already been mined, there is an estimated global reserve of this fossil fuel that could be more than 1 trillion tons.
- Infrastructure Is Currently In Place In Major Cities For Coal – all existing infrastructure is suitable for coal energy delivery.
- Coal Power Is Not Variable Like Some Renewables – unlike solar or wind which can be a variable power source on days that aren’t sunny or non windy days, coal can be burnt 24/7, and can even be burnt at higher amounts in times of need. This means it doesn’t need back up base load generators or other power sources like wind or solar might.
- Capture Carbon Storage & Other Technology Is Being Improved To Reduce Emissions From Coal Power Plants – As of 2017, coal energy is responsible for about 50% of the electricity being generated in the United States. Thanks to clean coal technologies, many of the emissions which are released during the combustion phase of this resource can be captured. This limits the potential damage to the environment and atmosphere while maintaining current infrastructures.
- Coal Can Be Converted Into Different Types Of Fuel – Coal can be converted into a gas or into a liquid. When this process has been completed, coal energy burns cleaner than it would if the natural resource were being burned in its natural state.
- Coal Power Plants Can Be Cheaper Than Gas Or Nuclear Plants – Energy sector specialists GHD and Solstice Development Services have estimated that building a 1,000 MW ultra-supercritical coal-power plant (USC) would cost about $2.2 billion and the electricity produced would cost about $40-$78 per MWh, while the electricity produced by a gas-fired power plant would cost between $69 and $115 per MWh.
- Has Helped Grow Economies In The Past – developed countries have benefited immensely from coal in the past. It has been used heavily to grow their economies and progress various industrial sectors
- Can Provide Energy Independence For Some Countries – brown coal in particular can provide a domestic source of energy, which gives countries independence from foreign energy supply. For example, Germany and Poland can both cut their dependence on Russian gas with the use of their own brown coal
- Some Estimates Of Coal Air Pollution Emissions Are Lower Than What Is Reported – some coal plants might not be as bad for air pollution as is traditionally thought. For example, emissions from Victoria’s (in Australia) power stations contributed at one point to less than 1 per cent of total mercury concentrations in the Latrobe Valley (abc.net.au). Also, the brown coal at Gippsland (Victoria, Australia) is relatively free of sulfur and nitrogen and produces less than 5% by weight of ash. (dynamicscience.com.au). Cities and places with coal power plants might like to look at the overall air quality and concentration of the main air toxins and contaminants in the area to get an idea of the plants’ impact on how healthy and breathable air is in the area.
- Some Estimates Of Mercury Emitted By Coal Burning Are Lower Than What Is Reported – mercury concentrations in the [Latrobe Valley] region [in Australia] are dominated by the atmospheric background and natural emissions from vegetation, soil and water. [So, they aren’t influenced as much by coal emissions]. Victorian brown coal actually has very little mercury … [and] Australian coal-fired power plants [mercury emissions are] quite low compared to others such as the United States (abc.net.au)
- Coal Waste By Products Can Be Used For Other Applications – such as for bricks, recycled fuel, and a sustainable form of concrete using coal fly ash (sciencedirect.com, and sciencedaily.com). In 1999 the EU used half of its coal fly ash and bottom ash in building materials (where fly ash can replace cement), and it used 87% of the gypsum from flue gas desulfurisation (world-nuclear.org). Captured carbon dioxide gas [from coal] can be used for enhanced oil recovery on a commercial basis where the CO2 acts to reduce the viscosity of the oil, enhancing its flow to recovery wells. It is then separated and re-injected (world-nuclear.org)
– vittana.org, alternative-energies.net, unearthed.greenpeace.org, abc.net.au, dynamicscience.com.au, sciencedirect.com, sciencedaily.com, world-nuclear.org
Coal Energy Cons
- Although Coal Is Cheap, It Has Been Heavily Subsidised and Protected In Some Countries – coal, natural gas and oil have been more heavily subsidised and protected in most countries compared to renewable and cleaner or less destructive forms of energy. This places an asterisk over the price of coal
- Emits Greenhouse Gases – carbon dioxide greenhouse gas is emitted when coal is combusted for fuel. Additional emissions are released through the mining and delivery processes. These emissions do not line up with the global goal to minimise climate change and global warming. Overall, the burning coal produces over 14 billion tonnes of carbon dioxide each year (world-nuclear.org)
- Emits Air Pollutants (and contributes to human health conditions and mortality rates) – such as NOx and SO2, which decreases air quality and can cause human health problems (such as lung cancer and cardiovascular disease), and mortality risks. When brown coal in particular is burnt, it releases a long list of poisonous heavy metals and toxic chemicals like sulphur dioxide, mercury, particulate matter and nitrogen oxides. The type of coal being burned can determine the toxins that are released. Winds can carry air pollutants from one region to another as well – so the spread of air contaminants is possible. Just as one example of coal and air pollution – Coal-fired power stations were responsible for 49% of all nitrous dioxide emissions in Australia in 2016-17 and 54% of sulfur dioxide emissions (theguardian.com). Cities should probably look at their overall air quality levels though, and poor air quality levels might be able to be related to coal plants or fossil fuel burning in the area (transport is another common cause).
- Air Pollutants From Coal Contribute to Acid Rain – When coal is burned the sulfur combines with oxygen and the sulfur oxides are released to the atmosphere. Sulfur dioxide (SO2) becomes sulfur trioxide (SO3) when reacting with oxygen in the air. This reacts with water molecules in the atmosphere to form sulfuric acid, a strong mineral acid. This makes rain acidic. (butane.chem.uiuc.edu)
- Air Contaminants From Coal Might Not Be Well Monitored – in some regions of the world, poor monitoring and control of air contaminants leads to air quality issues.
- Air Pollution From Coal Burning Costs The Health System Money – in Australia alone, it’s estimated the health cost is up to $800 million every year.
- Not Renewable/Has Finite Supplies – supplies are finite and will eventually run out, at which point we have to consider other forms of energy.
- Coal Mining Can Be Destructive To The Environment – potential pollution of groundwater tables and the removal of trees. There is also the added danger of having a fire begin in a coal mine. Wildlife can be affected, as well as there being permanent land erosion and degradation. On top of this, coal mining can emit methane (a GHG 20 to 25 stronger than C02)
- Coal Mining Can Also Be Harmful In Other Ways – Byproducts of coal mining including arsenic, sulfur dioxide, selenium, and mercury. Miners who inhale coal dust can develop a condition that is called Black Lung Disease, which can make it difficult for the person to breath and reduce their overall quality of life. In total, several million tons of unusable waste are produced annually because of coal energy and that stuff needs to go somewhere.
- Coal Burning Produces Radiation – Coal energy, when burned at a coal-fired power plant, produces more outward radiation exposure than a nuclear power plant would produce. The emissions are also linked to increased levels of asthma and lung cancer for local populations compared to other forms of energy.
- ‘Clean Coal’ Right Now Is Not Actually Clean – it can be a cleaner form of energy than regular coal plants without clean coal technology, but it’s still significantly more dirty in operation than nuclear and renewables right now
- Carbon Capture Can Be Uncertain – the full risks of capturing carbon from coal and putting it in the ground are still not known.
- Carbon Capture & Other ‘Clean Coal’ Technology Can Be Expensive – the technologies to convert current coal-fired plants to clean coal could greatly increase the energy costs for individual consumers. LiveScience estimates that some carbon capture and storage technologies could increase the price of energy by up to 75%.
- Some ‘Clean Coal’ Technology Isn’t Always Effective – bag filters [on coal plants] are less effective for [air pollution] particles referred to as PM 2.5, or particulate matter smaller than 2.5 microns (abc.net.au). Additionally, clean coal plants have had to be shut down before commissioning in several locations worldwide, and haven’t had the most consistent success
- ‘Clean Coal’ Technology Research and Development Has Taken Up A Lot Of Money Over The Last Few Decades – About $50 billion has been put towards the development and deployment of “traditional” clean coal technologies over the past 30 years (wikipedia.org). Some argue this money could have gone towards renewable technology instead
- Coal Plants Need To Be Topped Up With Fuel Regularly – coal plants need to be topped up with ongoing coal supplies to burn for energy. Compare this to solar for example which can continually absorb energy from the sun.
- Brown Coal Is An Inefficient Form Of Energy – BC is wet when it is extracted and burned. So, it takes more brown coal in quantity, and more mining, to produce the same amount of power from less black coal
- Brown Coal Can Be Uneconomic to Transport Long Distances – Victorian (in Australia) brown coal has a high moisture content, containing more moisture than black coal – it can contain up to 70 percent water. This high moisture content makes long distance transportation uneconomic and so brown coal is not currently used for export markets (environmentvictoria.org.au)
- There’s A Possibility Coal Plants Might Be Able To Manipulate Emissions Reporting & Auditing – waste incineration plants can do this in some countries when it comes to pollution third party auditing. There’s a possibility coal plants might be able to do this too (bettermeetsreality.com)
- Coal Waste Like Fly Ash Can Build Up, & Can Pollute – in places like Australia, coal fly ash can make up to one fifth of the total waste stream. It can contain high concentrations of heavy metals that can pollute water sources and seep into soil. Coal waste needs to be managed and treated properly, which can also cost money (abc.net.au)
- Coal Power Plants Can Be A Major User Of Water – to be fair, it’s not just coal that needs water for cooling purposes, but thermal power plants in general. What type of water is used and whether it is re-used or recycled plays a big role in the water footprint of power plants. But, solar and wind as energy sources can be less water intensive overall. (bettermeetsreality.com)
- Coal Power Plant Licenses Can Allow Investors & Plant Operators To Pollute The Environment – if licenses are granted for say 20 years at a time without any regulations on air pollution or carbon emissions, this can encourage investment in dirty and cheap coal energy, and puts no eco responsibility on plant operators (theage.com.au)
– vittana.org, energyinformative.org, unearthed.greenpeace.org, environmentvictoria.org.au, wikipedia.org, butane.chem.uiuc.edu, world-nuclear.org, bettermeetsreality.com, abc.net.au, theage.com.au