In this guide, we list the pros and cons of coal energy.
This guide forms part of a series of guides we have put together outlining the benefits and disadvantages of different energy sources and energy generation methods.
Summary – Coal Energy Pros & Cons
Can be cost effective and provide affordable electricity
Some remaining coal supply estimates are as high as hundreds of years (based on current known resources)
Power supply infrastructure established in many cities is currently set up for fossil fuels like coal
Not a variable power source (like solar or wind for example)
Has good power density/power per unit (black coal in particular)
Technology like air filters, and CCS systems can capture air contaminants and emissions from coal combustion
Coal can be converted into different types of fuel
Electricity from coal power plants can sometimes be cheaper in price than electricity from natural gas plants
Provides significant employment and income in major countries like China
Has, and continues to be a contributor to economic growth for major countries
Can help countries have better energy independence from other countries
Actual air pollution from coal combustion might be lower in some instances than what is usually reported
Some estimates of mercury emissions also 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 (and sometimes protected) in some countries (which helps keep coal prices competitive)
Is finite as a resource as a fossil fuel – not a renewable form of energy
Coal supplies at plants need to be topped up, unlike some renewable forms of energy
Emits greenhouse gases, and has one of the highest carbon footprints of all energy sources (and can leak methane during extraction at coal mines)
Contributes to outdoor air pollution via the release of various air toxins
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 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
Some ‘Clean Coal’ technology isn’t always effective
Brown coal is an inefficient form of energy
Brown coal can be uneconomic to transport long distances
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
Some reports indicate coal isn’t suitable for ramping up fast
Coal is cheap, widely available, has infrastructure already in place (for power grids for many cities around the world), and has a reasonable amount of resources/supplies still left.
It essentially offers a lot of affordable power supply, and has helped build and sustain economies over time.
However, the carbon dioxide and air toxins it can emit during combustion are seen as a major issue (when filters and carbon capturing devices aren’t used especially), and mining of coal can also lead to negative effects
Because of climate change and air pollution, countries like China are trying to transition to other forms of energy (other than coal) like natural gas, and renewables such as solar and wind.
Coal may offer several major economic and social benefits right now, and some major economies may depend on it, but transitioning to cleaner and more renewable energy sources as soon as feasibly possible seems like a smart strategy to hedge and protect against some of the major downsides.
*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 is a combustible sedimentary rock having a black or brownish-black color [and] coal consists of mostly carbon along with other elements such as hydrogen, nitrogen, sulfur and oxygen (alternative-energies.net)
Once coal has been mined/extracted, it needs to be cleaned (to remove unwanted materials) and processed, before it can be transported to a consumer for energy use.
One of the major ways coal is used for it’s energy is to produce electricity.
At coal power plants, coal is burnt/combusted to turn water into high pressure steam, and this steam turns a turbine to create electricity.
Coal Energy Pros
Cost Effective & Can Provide Affordable Electricity
Usually one of the cheaper forms of energy because of how energy dense coal is compared to how much it costs per unit of weight.
Brown coal in particular can be cheap.
When you take subsidies out of the equation, some sources indicate that brown coal energy in some places in the world can be about $30 per MWh compared to solar at about $70-$80 per MWh.
Prices though can ultimately depend on various factors like the market, the energy mix, the geographic location, and other factors.
Some Estimates Indicate There Is A Reasonable Supply Of Coal Left
According to one estimate, 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.
Many Cities’ Current Infrastructure Is Set Up For Coal & Fossil Fuels
Existing infrastructure in major countries like China is set up for coal and fossil fuels energy.
Solar and wind installed capacity on the other hand might struggle with energy loss due to not having infrastructure set up for it.
Coal Power Is Not Variable Like Some Renewables
Solar and wind energy for example can be variable due to their reliance on weather conditions.
Coal on the other hand can provide constant energy as long as coal is available to burn.
There’s additional benefits to a non variable energy source, such as not requiring energy storage and
Coal Has Good Energy Density
Compared to other energy sources, coal generally has good energy density, when measured in gigajoules or microjoules, per unit
Black coal might have better energy density when heated/combusted because it has less moisture and more carbon, compared to brown caol
Technology & Devices Exist To Capture Air Contaminants and Emissions From Coal Power Plants
For example, filters (and other devices) can catch air contaminants before they get into the atmosphere
Additionally, carbon capture devices can capture carbon dioxide before it gets into the atmosphere, and carbon storage can be used to store carbon underground.
Other CCS technology exists for carbon capture from coal energy.
Coal Can Be Converted Into Different Types Of Fuel
Coal can be converted into a gas, or into a liquid.
An additional benefit of this conversion is that coal energy can burn cleaner than it would if it were being burned in its natural state.
Prices For Electricity From New Coal Power Plants Can Be Cheaper Than Gas Fired Plants
[some specialists] have estimated that [electricity from] ultra-supercritical coal-power plants … 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.
Provides Significant Employment
Along with natural gas and oil, the coal industry is responsible for significant employment.
There’s direct employment, but also indirect employment in the form of all the associated employment of people not working in the coal industry, but who consult to it.
Has Helped Grow Economies In The Past. & Continues To Do So
Developed countries have benefited immensely from coal energy in the past.
It has been used heavily to grow their economies and help various industrial sectors progress and develop.
China is still heavily using coal energy right now in it’s energy mix, and it’s installed capacity of coal isn’t expected to peak until 2025 according to some estimates.
Can Provide Energy Independence For Some Countries
Brown coal in particular can provide a domestic source of energy, which gives countries independence whereby they aren’t as reliant on a 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 Reports Of Actual Coal Related Air Pollution Are Lower Than What Is Usually Reported
Some examples of lower than usually reported air pollution levels from coal plants are:
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 Usually Reported
It can be the same for mercury emissions. Although, it can be dependent on geographic location.
Some data on mercury emissions from coal power plants:
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
A few examples of the different uses of coal waste by-products …
General waste by products:
[coal waste by products might be used 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 desulfurization (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)
Coal Energy Cons
Although Coal Is Cheap, It Has Been Heavily Subsidised & Protected In Some Countries
Coal, natural gas and oil have been more heavily subsidised and protected in most countries compared to renewables and other energy sources, according to various reports.
This places an asterisk over the actual price of coal (when taking out subsidies, protectionism, and the years of development and investment it has had)
Coal Is Not Renewable & Has Finite Supplies
Supplies are finite and are expected to eventually run out, at which point we have to consider other forms of energy.
This is compared to renewable energy like solar or wind for example.
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 without needing to be refuelled.
Emits Greenhouse Gases, & Has High Carbon Footprint
Carbon dioxide greenhouse gas is emitted when coal is combusted for fuel, and also during the mining/extraction process.
Compared to other energy sources, coal usually has the highest carbon footprint of all.
Contributes To Outdoor Air Pollution
The combustion of fossil fuel like coal is one of the major causes of outdoor air pollution.
Air contaminants like NOx and SO2 are emitted when coal is burnt.
This impact air quality, and can also impact human health.
Brown coal in particular can emit 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.
Air pollution from coal power plants, and subsequent degradation of air quality might not be well monitored in some places in the world, compounding the issue.
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 into the atmosphere.
After a series of reactions in the atmosphere, rain can become acidic, and this is know as acid rain.
Acid rain can have a range of effects.
Air Pollution From Coal Power Stations Can Have Health Costs For Society
In Australia alone, various sources indicate the health cost to society can be in the hundreds of millions to billions of dollars.
Coal Mining Can Have A Range Of Environmental Effects
Mining coal, and mining different mineral out of the ground can have a range of potential negative environmental and other effects.
Coal Mining Can Harm Human Health
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.
There’s also coal mining related injuries and fatalities to consider on an annual basis.
Coal Burning Produces Radiation
Combustion of coal at a coal-fired power plant produces more outward radiation exposure than a nuclear power plant would produce according to some sources.
This could lead to increased levels of asthma and lung cancer for local populations.
‘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.
Full Risks Of Carbon Capture Still Aren’t Known
The full risks of capturing carbon from coal and putting it in the ground are still not known.
This is a potential concern long term.
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%.
As one example, new coal power plants with clean technology could be expensive, and pass on higher prices for coal electricity onto consumers – ‘[some specialists] have estimated that building a 1,000 MW ultra-supercritical coal-power plant (USC) would cost about $2.2 billion’
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
Brown Coal Is An Inefficient Form Of Energy
Brown coal 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 Isn’t Economically Feasible 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
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
Coal Power Plants Can Be A Major User Of Water
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
Read more about the water footprint of different industries in this guide.
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)
Coal Isn’t Suitable For Ramping Up Fast
Thermally lethargic technologies like coal and solid-fuel nuclear are physically incapable of fast ramping (wikipedia.org).
Combined cycle natural gas might be more suitable for this, like for example when fast ramping sources are needed to support variable renewable energy