‘Is Clean Coal an Act of Faith?’ by Anne Harris is a write up of a talk given to The Sheffield Humanist Society 3rd March 2010. A recording the presentation from the opposition, Terry Fox (TUC Clean Coal Task Force), this talk and contributions from the floor are available from http://www.radio4all.net/index.php/program/40349
Is Clean Coal an Act of Faith?
Coal is the dirtiest of all fossil fuels (Hansen, 2009), it releases a higher quantity of carbon dioxide per calorie of energy produced than oil or gas. The UK government is looking into new ‘clean coal’ technology, the idea behind this is that it is possible to capture and store the carbon dioxide produced in combustion of coal and prevent it being released into the atmosphere. Although organisations such as the Trades Union Congress and the government may be pushing an agenda of Carbon Capture and Storage (CCS) genuinely clean coal does not and cannot exist. This approach to addressing climate change will encourage more coal use, cause ecological destruction and human suffering, generate huge risks for the future and legitimise ‘business as usual’ thinking. At best Clean Coal is an act of faith.
In order to look at the true carbon and environmental output of coal and CCS technology, we must look at the whole life-cycle of coal, from the point at which it is mined, through transportation, combustion, CO2 extraction, CO2 transportation to CO2 storage. The ethical issues created by coal combustion are not limited to output of carbon dioxide, it is necessary to consider workers struggles, habitat destruction, future generations and human rights to get the whole picture of the problem.
We will start with what climate science says about how much fossil fuel we can use, and go on to look at what so-called ‘Clean Coal’ means, the problems and risks it poses, and why it is very much a ‘cross your fingers’ approach – an act of faith. We shall then look at why CCS and continuing to burn coal is ethically unacceptable.
|How much of the reserves can we afford to use?|
|Type of Fuel||Global Reserves||Contains Carbon (billion tonnes)?|
|Coal||848 billion tonnes||633|
|Gas||177,000 billion m3||87|
|Oil||162 billion tonnes||98|
Table derived from figures in Monbiot (2009).
This table shows the total figures for the known global reserves of fossil fuels in a state which makes it usable. The reserves are dominated by coal, and that coal is more carbon-intensive than oil. Figures published in Nature (Meinshausen et al, 2009) say that if we burn just one third of these reserves of carbon between now and 2050 it would give a 25% risk that global temperature rise would exceed 2oC.
The only reason why the huge expense of developing Carbon Capture and Storage makes sense is that coal is seen as a ‘cheap and abundant’ source of fuel. There are major companies with established interests in these huge reserves, multinational corporations such as Shell and Statoil. As well as less well known, but also powerful companies involved in the technology and infrastructure surrounding CCS. Therefore there is a powerful group arguing for using these resources, rather than using perfectly adequate measures of storing carbon, as coal, left in the ground. The imperative for climate safety is to rapidly limit our carbon emissions so does CCS help with that in time?
There are three methods of removing the carbon dioxide from the coal combustion process. These are pre-combustion capture, post combustion scrubbing and oxyfuel combustion. Each method reduces efficiency of the power station by around one quarter, so the total quantity of coal burned has to increase in order to supply the same quantity of energy and power the CCS process (Fauset, 2008:39). Of the three methods only post combustion scrubbing can be retrofitted to existing power stations as pre-combustion capture involves gasifying to separate out the hydrogen and carbon dioxide prior to burning. Oxyfuel combustion involves burning the coal in pure oxygen and so will require a constant source of this as well, this method is the least developed (Metz et al., 2005).
Many of the elements of these technologies are at the research or demonstration phase. Some elements have been operationalised in a different context, or at a different scale to what would be required for ‘clean coal.’ For example CO2 from natural gas post combustion processing has been has been injected into oil wells for Enhanced Oil Recovery (EOR), this has been at a minuscule scale compared to what would be required for CCS from coal fired power stations.
Time Scales for CCS
In order to avert catastrophic climate change we need to reduce emissions by 50% before 2050 Metz et al, 2005). If we burn more than a third of global usable reserves of coal between now and 2050 it would give a 25% risk that global temperature rise would exceed 2oC (Meinshausen et al, 2009). In order for carbon capture and storage to provide any useful reduction in global warming it needs to be viable now.
In his article in The New Scientist Pearce (2008) states that there is disagreement about how quickly CCS could become commercially viable. He states that The Massachusetts Institute of Technology believe that the first commercial CCS will take till 2030 to be on line. The Edison Electric Institute, (who are a large US power generators) research suggests that commercial deployment of CCS for emissions from large coal-burning power stations will require 25 years of research and development and cost about $20 billion, giving usable results by 2035 (cited by Pearce, 2008). Shell are developing CCS but does not foresee CCS being in widespread use until 2050 (cited by Pearce, 2008). If the companies involved cannot agree on when the technology will be available, how can we know it will be in time?
Meanwhile, the plan is to build unabated power stations which are CCS ready. In reality this means that there is a space within the powerstation complex which could be used for the technology, once it has been created and fully tested to be retrofitted. In February 2010 Labour defeated an amendment to the Energy Bill calling for Emissions Performance Standards on all new power stations, arguing that it could harm investment in new coal power stations. Their priority is to build new coal-fired power stations, despite saying they agree with the Committee on Climate Change who say that ‘there will be a limited role for unabated coal [without CCS] in the 2020s’ (Ruddock, 2010). Until these new power stations are retrofitted they are simply adding to the problem.
Although there are differing opinions on the time it will take for CCS, if successfully created, to be fitted to new, and old power stations, no-one in industry is suggesting that this will be quickly enough to contribute significantly to reducing carbon dioxide levels in the environment. If this is the case, why are governments pushing this technology rather than looking into energy use reduction and investing in renewable technology which offers far less damaging clean energy?
Ways to Reduce Atmospheric CO2
A report by Viebahn, of the German Aerospace Center (2007), shows that electricity produced from Natural gas combined heat and power plants results are nearly as low a level of emissions as a fully functioning CCS power plants are expected to be, whilst using a well understood technology that is available right now. This is because the heat by-product from power stations is fully utilised, reducing inefficiencies.
Viebahn (2007) estimates that at best CCS will reduce greenhouse gas emissions from coal-fired power stations by little more than two-thirds. That compares with life-cycle emissions for most renewable energy technologies that are 1 to 4 per cent of those from burning coal. If we increased our use of renewables then we can supply sufficient energy without releasing significant amounts more carbon dioxide, though it does not look likely that we will be able to supply the same quantity of energy as what we currently consume. To increase the amount of renewable energy sources would require substantial government investment and an acceptance that we have to dramatically alter our habits to prevent further climate change.
Graphs from Viebahn (2007: 31)
Viebahn compares two scenarios for Germany. The first graph, ECO, predicts the energy saving, and renewable energy (as outlined in the ‘sustainable energy scenario’, BMU (2004)), resulting in a lower power requirement. The second graph, predicts CCS to be a main part of a climate protection strategy under business-as-usual conditions. Notably the amount of CO2 from coal, prior to CCS technology coming into action, is much higher than where there is real investment in renewables and energy efficiency.
The Institute of Mechanical Engineers (2009) and The Institute of Chemical Engineers are optimistic about CCS. They see clean coal as an opportunity for the UK to be world leaders in a field of global value and believe it will provide jobs in research and development. It is seen as a business opportunity for Britain, but the Institute of Mechanical Engineers (2009) report calls for a 50% cut in the use of coal for energy production, and sees the importance of renewables.
The Bigger Picture
Coal plays an important role in industry in this country beyond its capacity to be burnt to produce energy. It is also an important component for making steel, this will be more important for a sustainable future than burning coal for power at low levels of efficiency. Steel is needed to build wind and tidal turbines and other items which are essential for a low carbon economy. From this perspective it seems irresponsible to generate electricity by burning coal when there are other methods of energy production available. Coal is however needed for producing new steel.
In a Centre for Alternative Technology report (2007) a 20 year programme of energy efficiency renovation and refurbishment that could reduce the energy use of Britain’s 25 million homes by 57%. To make this saving would require a huge investment of money, science and jobs but is guaranteed to make a real reduction in green house gas emissions.
A report from the Institute of Mechanical Engineers (2009) showed that we can realistically reduce our energy demand by insulating offices and public buildings, and using more efficient electrical devices. This could reduce 50% of all building energy use. This is only one way in which we can reduce our energy demands by becoming more efficient with energy.
Extraction of Coal
The governments use of coal-fired power stations is already disrupting community and having ecologically destructive effects. In the UK there are currently more than 33 open cast mines in operation. Since the National Union of Miners (NUM) was defeated in 1985 mining has moved towards a less labour intensive, cheaper, more ecologically damaging system of open cast or surface mining. This method involves removing the top soil and then extracting coal from large open holes. This is far more locally destructive than the deep mining industry which Thatcher destroyed during the miners’ strikes, as it removes the soil and rock covering the coal and scarring the landscape. Wildlife is displaced, heritage sites are lost, public space and footpaths are removed, soil structure is ruined, water systems are polluted (Sengupta, 1993) and trees and hedgerows are destroyed. Coal companies claim they will restore the area, but this tends to be a token gesture at best.
Open casting requires far fewer employees and the jobs from this work are rolling, so when one mine closes another comes on line and the staff are moved to the new site from the old. Therefore very few jobs are created for local people and the local economy is damaged as money moves away to the home towns of employees. The local jobs created are generally security and cleaning staff (as HJ Banks admitted in a public meeting about the proposed mine in the North East). The NUM is against open cast on the basis that it does not provide local skilled jobs like deep mining used to. Open cast mining reduces work in the local communities as land is compulsorily purchased to make way for the mines and tenant farmers are evicted. This land may previously have provided jobs from agriculture and forestry, local tourism is also damaged. Mines make villages less attractive places to live and those with the means to do so move away, leaving less money entering the local economy, creating a downwards cycle of social instability.
Open cast mining releases more atmospheric pollutants than deep mining, such as dust and other particulate matter. As coal runs in seams it is concentrated around specific communities (see appendix 1), communities already damaged by the miners strikes and subsequent unemployment are further degraded. The particulate matter from the mines causes damaging effects to local population. The Coal Health Study, Douglasdale Edition (Stramler, 2009) found that currently, chronic obstructive pulmonary disease incidence in the Douglasdale Medical Practice is over twice the UK average, up 60% from 2005, during which time the extent of open cast coal mining activities increased in the area. A sampling of other comparative health statistics also reveals amplified incidence rates in Douglasdale: asthma and hypertension up 44%, hypothyroidism up 80%, and cancer rates up 250% over the 4 years to 2009. Open cast mining degrades air quality (Sengupta, 1993) as dust is released into the atmosphere.
Imports of Coal
The damaging effects of open cast mining in this country does not show the whole picture. 70% of the coal we burn is imported, largely from Russia and South Africa (Association of Coal Importers, online). Despite worries over Russian gas supply we import much more on Russian coal than gas. Importing fuels does not create jobs in this country and locks us into relying on politically fraught relationships with other countries. Indonesia and Colombia are supplying ever more of our coal. Columbia is a country ravaged by civil war, with a reputation for murders of trade unionists and high fatality levels in its mines. Indigenous people are displaced from their inherited land, by government and mining companies (Greenpeace, 2009(a): 37). Paramilitaries and government deny basic human rights.
In Indonesia coal mining is associated with a long list of negative social and environment impacts. These include forcible eviction of local communities (including indigenous communities) from their land, leading to poverty and social dislocation. Violent police action to enforce development of mines often results in human rights abuses. There is no transparency over how decisions about issuing licences are made, despite Indonesian laws which require this. Productive farmland growing food crops to feed local people are destroyed to make way for open cast coal mines, ruining local livelihoods. Heavy coal lorries cause damage to local roads and the mines increase dust and noise pollution. Destruction of rainforests, which provide livelihoods for local communities as well as habitat for wildlife, to make way for mines, accelerates climate change and increases the likelihood of flooding (Greenpeace, 2009(a)).
Enhanced Oil Recovery and Carbon Dioxide Storage
The idea that this is ‘storage’ is an intentional white herring. Are we really storing something we need and want? In reality this is dumping, by another name, because dumping is illegal under various international protocols. In order to safely lock away the CO2 so that it is not released in to our atmosphere we need to be confident that it will stay where we put it. As the time period we need to be sure of is indefinite, we simply cannot test ‘storage facilities’ this long. The Weyburn-Midale CO2 project claims to be the world’s first CO2 measuring, monitoring and verification initiative. Yet the length of the study is merely 10 years (IEA, online). Can the long term safety be presumed to last indefinitely after such a short trial period? This doesn’t stand up to scientific scrutiny.
The only ‘storage’ of carbon dioxide currently in industrial use is through Enhanced Oil Extraction. The CO2 produced by the Great Plains Synfuels Plant in the US and is transported to the Weyburn oilfield Canada via 330km purpose-built pipeline. CO2 injection is expected to produce at least 130 million barrels of incremental oil, which should extend the life of the oilfield by some 25 years (IEA, online 2010). Whether or not the CO2 stays in the space once filled by oil is unclear. There does not appear to be any research published about this suggesting that those running the EOR program are not testing to find if the CO2 remains in place. As a method of removing CO2 from the atmosphere, this is a non-starter. The CO2 is used to extract more fossil fuels which are then burnt increasing, not reducing, global warming.
A proposed BP project is to build a pre-combustion power station for £500m and capture 26 million tonnes of CO2, this CO2 will then be used to extract an extra 40 million barrels of oil, which when burnt would produce 13 million tonnes of CO2 (Fauset, 2008 citing BP, 2005 and Bliss, 2008). Such a plant would capture only 85% of CO2 produced, and use 20% more coal, with all the environmental effects that has. This whole system will generate more fossil fuels, the emissions from which will accelerate climate change unless these too are captured and stored. This plan increases our reliance on fossil fuels rather than forcing us to look into energy reduction and efficiency.
Were the techniques used in EOR used in purely ‘storage’ methods, would using the space left by depleted oil and gas fields be viable? The furthest-advanced depleted oil storage test project is Upper Frio on the Gulf coast of Texas. Engineers have injected 1,600 tonnes of CO2 into a sandstone formation. The rock, which once contained oil, is now flooded with salt water. An early report on the Frio project (Kharaka, 2006) points to a possible danger of storing CO2 in formations like these. The CO2 has acidified the brine, allowing it to dissolve metal-oxide minerals in the rock, which might eventually create tunnels in the cap rock through which CO2 might escape. Other scientists think that this process may further seal the CO2 into the chamber. Without being tested for the amount of time we need to use these methods for, we cannot know which of these hypothesis are true.
The possibility of a sudden or even a slow release of the captured CO2 into the atmosphere or into water is a real risk. Pearce (2008), points out that a leakage rate of 0.01% a year from a geological field used to store CO2, a suggested industry standard, would see almost two-thirds of the gas released back into the atmosphere and oceans within 10,000 years which is not very long in geological time scales. Geoscientists are not sure what the effects of CO2 storage underground would be and therefore feel research is needed, however we need to ask if there is not another solution.
A sudden release of carbon dioxide would have disastrous and sudden effects. Sudden releases of CO2 have happened before. In 1986 1,700 people were killed in Cameroon, when Lake Nyos which has naturally occurring stratifications saturated with CO2, released a cubic kilometre of the gas (BBC, 1986(a)). The cause of the release is unknown but may have been as simple as an unbalance caused by cool rainwater on one side of the lake. If we were to begin to store the enormous quantity of CO2, the world’s human population generates annually, into unstable geological or marine environments, earthquakes and climatic changes could result in a sudden CO2 release wiping out life in large areas and accelerating climate change.
Another method of storage being considered is deep sea storage. Pumping CO2 to the bottom of the sea may seem like a convenient solution. The gas will liquefy at extreme pressures created with depth (Fauset, 2008). This is a really short sighted answer as we are still learning about the deep sea bed (BBC, 2010(b)). We risk destroying lifeforms we know little, if anything about and irreparably disrupting fragile ecosystems. These ecosystems do not exist in isolation but feed into the entire underwater environment. Even gradual release of carbon dioxide into the sea will have an acidifying affect. This could potentially kill off plankton, which is the basis of almost all life in the sea and aids in the ocean’s capacity to absorb CO2 which would result in ecological collapse.
Transportation of Captured CO2
If scientists are able to get CCS running at commercial scale then a new massive infrastructure will have to be built to transport the extracted CO2, as when burnt, coal produces about three times its weight of CO2, which has to be compressed and transported to storage. A study by the International Energy Agency suggests that the EU would need 150,000 kilometres of pipeline to trunk its CO2 emissions to the North Sea (Pearce, 2008). If depleted oil fields or deep sea storage are used then it would make most sense for power stations to be built near the ultimate end point of the CO2. This means that retro-fitting existing coal fired power stations with CCS is unlikely to be viable as the transportation will cost too much. If CCS only comes on line in 2050 as Shell predict, the oil platforms and other oil related infrastructure which would be useful for the transportation of CO2 would already have been removed.
A new transportation system for the waste CO2 will cause further disruption to the environment. This network will be vulnerable to terrorism in an unstable world due to resource shortages. Moving large amounts CO2 of will require more energy, which is likely to be generated from fuels which emit CO2.
So What is the Answer?
If clean coal (CCS) is the answer we are not asking the right question. The question is not how can we get rid of this CO2 we are are creating to reduce the effects of climate change. The question is how can we live sustainably on this planet. The answer is much bigger than simply looking at the carbon footprints of nations and more complex than burying waste out of sight and out of mind. Energy companies, supporters of CCS and the government say they are working to keep the lights on and so CCS is the answer. The harsh reality is that the lights will probably go off as we need to reduce our demand dramatically and look for real solutions, not quick fixes. Nationally we need to cut our emissions to a sustainable level, we have to move away from lifestyles revolving around computer screens, individualistic behaviour and consumerism. We need to recreate community and share resources, rather than all of us owning things which we only use occasionally. The answer is not about moving backwards to times of old, but moving forward to sensible technology use, human interaction, fewer but better quality personal possessions, energy efficiency and robust communities.
The energy we use must really be clean. It has to come from renewables and energy efficiency measures are vital. Clean coal and nuclear simply do not offer the answers. Green jobs, from the renewable industry, sustainable farming methods and increased localisation are central to this. Genuine sustainable practice produces more jobs, as the example of organic agriculture shows. Having limitless energy encourages companies to cut labour costs and increase mechanisation. A reduction in energy availability will supply more people with better jobs and working conditions as their labour will be valued, rather than being seen as commodities replaceable by machines if they assert their rights to fair working conditions.
Other nations put the UK to shame; Germany employs a quarter of a million people in the renewable energy industry which brings huge benefits to its domestic economy (Greenpeace, online(b)). China is now the fifth biggest user of wind energy in the world and built more wind turbines in a year than the UK has ever (GWEC, online).
The reality is that we need to drastically cut emissions. CCS is unlikely to come on line in time to prevent a 2oCrise in global temperatures. The money and scientists time would be better invested in renewables which do not leave massive amounts of unnecessary ‘stored’ CO2 or nuclear waste. Time is short, hard questions need to be answered, now is not the time for delay and procrastination whilst waiting for a technological fix, it is time to work together to reduce our demand on the planet’s resources.
Conclusion: Is clean coal an act of faith?
Clean coal is an act of faith in corporations and governments who push a business as usual approach and rely on technology to solve societal problems. It enables us to continue using resources in a destructive way, rather than reduce demand. Investing in new technology delays looking at the real issues of over consumption and asking difficult questions with widespread consequences.
Combustion of coal ignores the problems of extraction from the earth, transportation, human rights, relationships between nations, and storage of a hazardous product. It will leave a trail of destruction in its path and a legacy of waste for future generations.
Clean coal relies on poor maths; corporations say CCS may not be ready before 2050, yet the UK government believe it will be operational by 2020 (Fauset, 2008). Either way CCS is not expected to reduce atmospheric carbon dioxide before 2015, by which time we need to be releasing less green house gas emissions than we do presently.
From Guardian, 14/08/09
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