Image source: Scientific American (courtesy of American Electric Power).

Two pieces of news provide evidence of a fightback by coal. American Electric Power’s Mountaineer plant in West Virginia is reporting significant success for its small scale carbon capture project. And the UK has just licensed exploratory boreholes for offshore Underground Coal Gasification (UCG), a woefully under-researched technology that may make CO2 sequestration easier. The scale of the challenge facing the globe’s coal users is enormous but with determined research and development, the fuel may remain usable for power generation in a low-carbon world.

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Mountaineer
Vattenfall’s Schwarze Pumpe coal plant has been separating CO2 for a year or so. It hasn’t been putting the gas back into the ground because of resistance from citizens not wanting CO2 under their back yards. AEP started collecting and storing some of the CO2 from its Mountaineer electric power plant in early autumn 2009 using Alstom’s chilled ammonia process and injected the gas into permeable rocks 2.5km underneath the plant. Today’s process captures the CO2 from just 20 MW of the plant’s output. An upscaling of the plant will multiply this ten-fold by 2015.

Today (Wednesday 9 December 2009), the Wall Street Journal reports that the plant’s operators are pleased with the early success. AEP says that the energy penalty from operating the carbon dioxide separation and sequestering process is less than expected. (The Alstom process uses energy to heat the ammonia to separate the CO2 after it has been captured.) AEP’s CEO is reported as saying that the cost increase is no more than 4 US cents a kilowatt hour. Even this, however, would approximately double the cost of electricity produced at the plant. The optimism at AEP matches Vattenfall’s cautiously upbeat projections for the long-run cost of CCS when capturing the CO2 from a large power station’s entire output.

Clean Coal Ltd
Underground Coal Gasification (UGC) drives off useful combustible gases from coal seams. The gases are then burnt to produce electricity in a conventional gas power station. The technology has been known about for a century or more but technological advances have been slow. In recent years, the level of interest around the world has increased, partly as a result of concerns about climate change but also because of worries over the long-term availability of natural gas.

UGC is a ‘clean’ process in that it avoids the need for mining and burning coal and extracting sulphur and other pollutants. But it does face real environmental challenges in, for example, avoiding the pollution of local water supplies around the gasification sites. UGC is also not truly ‘clean’ in that it offers only a marginal improvement on conventional coal power stations in the amount of CO2 it produces. (This fact tends not to be mentioned by UGC proponents.) The world leader in UGC, Linc Energy of Australia, puts CO2 output per kWh of electricity at around 750 grams, compared to 400 grams for a combined cycle gas-fired power station.

The advantage of UGC is that it may offer cheaper sequestration of CO2 than a conventional coal station as well as much lower capital costs to build than a surface coal gasification plant. The gas coming up from the coal seam will be largely hydrogen, carbon monoxide, methane, and carbon dioxide. CO2 can be stripped from the combustible gases relatively easily because it is at high pressure. The remaining gases are then burnt in a gas turbine, producing water and nearly pure CO2. It may – only may – be possible to re-inject the gas into the coal seam for permanent storage. Some industry proponents think that this technique will eventually offer the lowest cost carbon capture and storage from coal.

The UK government has just licensed some experimental wells to be drilled by Clean Coal Ltd, a US/UK company run by industry pioneers. The wells will be in thin seams of offshore coal that would never be economical to exploit by conventional mining techniques. Offshore drilling also avoids some of the problems of subsidence that may occur when the coal is gasified underground in onshore locations.

The company’s press release says:

The UK Coal Authority has awarded Clean Coal Ltd licences to investigate the potential for underground coal gasification at 5 sites in the UK.  If the investigations over the next 12-18 months prove to be successful, commercial operations could start by 2014/15 and could lead to underground coal gasification producing 3-5% of the UK’s total energy requirement by that date.

This statement is over-ambitious. Other UCG projects around the world have taken much longer and gas production from underground coal is still something of an art. Although the Soviet Union ran UCG plants, only one of these remains open today. One of the leading scientists in the field, Dr Julio Friedmann of the US Lawrence Livermore lab, says, ‘A large number of basic science questions remain in the field of UCG.’[1]

Importantly, the Clean Coal press release is very vague about carbon capture and storage at its UK sites. Powerfuel, which is intending to use mined coal for surface gasification in Yorkshire, has been more specific and recently achieved EU funding for its plans. Without CO2 capture, Clean Coal Ltd is unlikely to be able to move forward in the UK or elsewhere, but the quickening worldwide pace of interest in UCG is a good sign.

The UK’s huge reserves of coal make it particularly important that the country invests in the research and development necessary to take the technology forward. Unfortunately, as ever, we are late to the game. China has graduated over 100 PhDs in UCG from one mining university and Linc in Australia is far more advanced with its plans for onshore gasification. As with several other technologies, the arguments for investing hundreds of millions in UK research and development over the next five years are overwhelmingly strong.

Footnote
[1] S. Julio Friedmann, ‘Accelerating Development of Underground Coal Gasification: Priorities and Challenges for U.S. Research and Development’, Coal Without Carbon: An Investment Plan for Federal Action (Clean Air Task Force report, September 2009), p. 8; available here in PDF format.

Image source: The Sydney Institute.

Professor Ian Plimer is one of the most influential global warming sceptics. A university academic in Australia, his trenchant views on climate change have helped persuade opposition politicians in his home country to back away from supporting schemes to reduce emissions. His book Heaven and Earth: Global Warming: The Missing Science (reviewed here last month) remains a best-seller in the UK.

He spoke in central London on 1 December at a meeting organized by the anti-EU United Kingdom Independence Party (UKIP). The material in the talk was largely taken from his book, though his language was even more open and unrestrained. Unsurprisingly, in view of the controversy over the content of recently exposed CRU emails, he repeatedly used the word ‘fraud’ or ‘fraudulent’ to characterize the views of his opponents. He described his critics as ‘rent-seekers’ who spent their time seeking out the next research grant.

This article takes a small number of the more controversial statements made by Professor Plimer and sets them against the standard scientific view.

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The role of CO2 in climate change
The burning of fossil fuels and the cutting down of forests adds to CO2 in the atmosphere. Carbon dioxide acts as a blanket, assisting the world’s atmosphere in retaining heat. More CO2 means more heat retention, say the textbooks. If we continue adding global warming gases, global temperatures will rise.

Does Plimer agree with this? During the talk he said that ‘doubling CO2 would have very little effect on temperature’. Higher CO2 levels in the future would have ‘negligible’ impact. At another time he said it would have absolutely no effect.

In a brief chat after the speech, I asked the professor to be more specific. What was his estimate of the impact so far on global temperatures of the CO2 mankind has added to the atmosphere? ’0.1 to 0.3 degrees’ (Celsius) was his response. The conventional scientific answer to this question might be about three times this figure.

Professor Plimer went on to say that his figures are lower than the IPCC estimates because the standard science is wrong about the absorption of CO2 in natural sinks such as the oceans. The typical residence time of carbon dioxide in the atmosphere is seven or eight years, he said. This is a much, much lower figure than proposed by conventional science. The standard view, sometimes called the Bern Carbon Cycle model, sees some of a pulse of new CO2 being removed rapidly from the atmosphere but also suggests that a portion remains for hundreds of years.

I responded to Professor Plimer’s remark by asking how his views on the rapid absorption of CO2 by natural sinks could be compatible with the observed yearly growth in the atmospheric concentrations of the gas since the beginning of the industrial revolution. In 1800, CO2 accounted for about 280 parts per million of the global atmosphere. Since then, concentrations have risen to nearly 390 ppm. CO2 arising from fossil fuel combustion has a different mix of carbon isotopes to the existing ambient gas. From many analyses using this and other parts of science we know that approximately half the CO2 added to the atmosphere by man is still there. (In the body of his talk the professor asserted that the assessment of how much fossil fuel CO2 is entering the atmosphere comes from a ‘dodgy calculation’ and he does not accept isotope analysis as a way of determining the source of carbon dioxide.) I wanted to understand how Plimer’s views on the short life of CO2 in the atmosphere could be made consistent with the rate of rise of observed CO2 levels since industrialization began.

He answered by saying that science was wrong to assume that the pre-industrial atmosphere held 280 parts per million of CO2. It was actually much higher, he said. The net addition to global CO2 levels by the burning of fossil fuel is therefore implicitly substantially lower than science suggests. Plimer says that measuring techniques are inadequate and that proper measurement would show that nineteenth- and early-twentieth-century CO2 levels were much higher than is assumed and very much more variable. He said to me that the belching of carbon dioxide by volcanoes would, for example, have produced short-lived but large rises in greenhouse gas concentrations. The charts that show stable atmospheric concentrations prior to the industrial revolution are therefore wrong, Plimer said.

In the body of the talk Professor Plimer attacked the quality of even today’s Mauna Loa data. He said that the measurement techniques were flawed and that the nearby volcano emits considerable amounts of CO2 which affects the quality of the record. 86% of all the observations were rejected, he said, and only data that accorded with the scientists’ prejudices was used. The professor did not, however, mention that many other sites around the world also measure CO2 concentrations and all of these stations report the same trend. (Absolute levels are different, inter alia, because of seasonal variations in CO2 concentration in different parts of the world resulting from plant growth.)

In the space of a short conversation, Professor Plimer attacked the foundations of climate science. He said that we overestimate the impact of CO2 on climate, that carbon dioxide is absorbed by sinks very rapidly, and, finally, that the standard measures of greenhouse gas levels over the last two hundred years are substantially in error, both now and in the past. In other words, almost everything that mainstream science believes about carbon dioxide in the atmosphere is incorrect. Fifty years’ work from scientists working independently all over the world on these issues has been misdirected, flawed, biased, and ignorant.

The assertion that scientists have systematically understated CO2 levels before the industrial revolution is particularly striking. To my knowledge, no one else has ever recently suggested that the stable pre-industrial level of 280 ppm is substantially inaccurate. The sources of this figure, such as measurements from the air trapped in ice cores, are usually considered to provide robust information. The number of scientists in the world who accept Professor Plimer’s views on this issue is vanishingly small. As far as I know, none of the other leading sceptics agree with him on this issue.

But he has to believe that the standard charts are wrong, even if this makes him even more at odds with the scientific establishment on this issue than other sceptics. If CO2 has risen by over 100 ppm in the last couple of centuries, he would have to accept that the gas has a much longer residence time in the atmosphere than he hypothesizes. And this would be incompatible with his view that CO2 is only responsible for ’0.1 to 0.3′ degrees of the rise in temperature since large-scale burning of fossil fuels began.

However, Professor Plimer had not even been consistent about whether world temperatures had risen at all. At some points in the body of his talk, he said that levels were rising, but this is ‘normal’. At other points, he said it was falling or stable. At yet other moments, he acknowledged some regional warming but said that large areas of the globe were getting colder. I believe that a dispassionate observer listening to Professor Plimer would have struggled to understand what he really believed about temperature rises, absolute CO2 levels or, most importantly, the effect of CO2 levels on temperature.

Nevertheless, he railed strongly against the theoreticians and the careful scientists who work on climate change. His principal charge was that they never go out into the real world to make their own observations. He said that they were ‘people in basements’ running computer models to appeal to their political masters and that only the sceptics were real scientists. Conventional science and its models made you ‘bang your head with boredom’. By contrast, he said that his thoughts on climate change provided a ‘far more evocative and sensual’ story and are therefore more likely to be right than conventional science.

Image source: Taiga Company.

1) If you buy just one new appliance in 2010, make it a really efficient fridge-freezer. The improvements in the energy use of the best fridge-freezers have been really impressive in the last few years. If you have an old refrigerator, it may be responsible for as much as a sixth of your electricity bill. A good new machine might use less than a half as much power, particularly if it is not too large. A second benefit is that by choosing to buy a really efficient refrigerator you will be sending a clear signal to the manufacturers that energy consumption matters. An impressive new web site – www.energytariff.co.uk – allows you to compare the electricity used by almost all the appliances currently in UK shops. You can make well-informed choices from your computer.

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2) Buy fewer, better clothes that are easy to wash. The worldwide textile manufacturing industry is a major user of energy. Additionally, growing natural fibres such as cotton or wool creates substantial volumes of emissions. A light woollen sweater might be responsible for over 40 kilograms of emissions before it gets to the shop. Even a T-shirt can embody over 6 kilograms of CO2 and other greenhouse gases. The average Briton buys seven of these a year. Could you make do with buying fewer, and making sure that they last longer? Buy organic cotton and you also know that your garment hasn’t added to the serious problems of pesticide pollution in central Asia. Can you switch to man-made fibres for some of your clothing? These fabrics generally last longer and can be washed at low temperatures, using less energy.

3) Think about trading in your car for membership in a car-share club. If you are typical, you use your car for one hour a day but pay for all 24. A car sitting at the kerb has to be insured, financed and maintained even if you hardly use it. Commercially run ‘car clubs’ are growing fast in many cities. They offer rentals from as little as £3.95 an hour or cars can be hired by the week from locations within a few minutes’ walk of your home. Car clubs reduce the cost of motoring for many people and each rented vehicle takes several private cars off the road. If there are no clubs in your area, simply sharing a car with neighbours may be a good alternative.

4) Look at the costs and benefits of putting solar panels on your roof. In April next year the government is introducing a new scheme to persuade us to generate our own electricity from photovoltaic panels. For every unit of electricity produced, the householder will get paid over 36p, around three times the price we are currently paying the electricity company for the power that we use. Solar panels are also coming down in price, meaning that on south-facing roofs in southern Britain you can expect a financial return of about 7% a year on your investment. It isn’t riches, but it certainly beats the interest you can get in a bank. Equally important, families that generate their own electricity seem to become more conscious of their energy consumption and focus successfully on cutting all their utility bills.

5) Eat less beef. The intensive rearing of cattle is a major contributor to greenhouse gases. These animals produce methane in their digestive processes and slurry heaps also generate large amounts of this powerful global-warming gas. What’s more, cows on most farms are fed large amounts of maize and other feed during the winter months. Growing these grains took energy and considerable amounts of artificial fertilizers. And as more and more of the world’s population demands meat in their diets, the pressure to cut down forests to create open pasture land increases. Perhaps 20% of the average Western carbon footprint is created in the food production chain and reducing the amount of beef eaten is an important step you can take to reduce this figure.

6) Try the new energy-efficient lights – LEDs. Many homes have replaced all their larger bulbs with energy-efficiency fluorescent lights. But many homes still have tens of halogen bulbs in kitchens and bathrooms. They use a lot of power and regularly need replacing. A new technology – LED lighting – uses only tiny amounts of electricity and directly replaces the small halogen downlighters. It’s only really in the past year that LED lights have become realistic alternatives. Before, they tended to have an unattractive blue colour and not produce enough light. But after recent improvements, now is the time to try some in your kitchen. They’re not cheap, but they’ll save significant amounts of electricity and will last for decades.

7) Keep your electronic devices for longer. Some of Apple’s fancy new computers have footprints of about half a tonne of CO2. This may be substantially greater than the CO2 produced generating the electricity that the computer uses in its lifetime. This could also be true for your new phone or your laptop. Although no one argues that you should waste power by unnecessarily leaving your gadgets on, the main focus should be on keeping them for longer. Doubling the average lifetime of our PCs and mobile phones would have a much more important impact than always turning them off at the mains socket.

8) Get better central heating controls. We all know that houses should be better insulated and have more efficient boilers. But for some households it may be simpler and less expensive to improve the heating controls. Check that all the household radiators have thermostatic valves. Make sure that they are turned off in rarely used rooms. Should your central heating be programmed to turn off earlier in the evening? Can you install a new computerised thermostat, such as the Dataterm (www.warmworld.co.uk), which will intelligently work out when your heating needs to be on or off? Running your heating with more care can save at least as much as investing in a new boiler. It doesn’t necessarily require you to run your house at a lower and less comfortable temperature.

9) Use the train to get to your holiday. Why not catch a train to the Mediterranean rather than driving or flying? The trip from London to Marseille can take as little as six and a half hours and you get to see something of France on the way. Book in advance and the one-way price is only £62, no more than a typical air fare. It’s similar with train travel in the UK. Going to popular UK holiday destinations by rail will almost certainly save you time and money and you can usually hire a car at the resort when you need it. Not flying to your holiday destination will probably reduce your carbon footprint by at least as much as any of the other choices in this list.

10) Grow some of your own food. Enthusiastically cultivated, a standard urban allotment can provide all the vegetables for a family of four for half of the year. In our household, we’re still eating home-produced tomatoes and lettuces grown under cover. If these vegetables had been grown in a heated Dutch greenhouse using large amounts of artificial fertilizer, shipped in a refrigerated lorry to a huge warehouse and then sold from an open chiller cabinet in a supermarket to which we’d driven, the carbon cost would be a thousand times greater. The advantages of local food are sometimes exaggerated: the greenhouse gas cost of South African apples may be no greater than English fruit kept in a cold store for months. But the footprint of seasonal produce that you grow yourself is tiny, and may even help wean your family off processed food.

11) Support international agencies trying to decrease the worldwide growth of population. The world now has over 6.7bn people, probably rising to well over 9bn by 2050. Each additional person adds to the strain on the planet’s ecology. Mike Berners-Lee, a leading researcher on carbon footprints, says in his new book, How Bad Are Bananas?, that a baby born today will add almost 400 tonnes to the UK’s emissions over his or her lifetime, even if we reduce greenhouse gases as fast as the government intends over the next decades. Cutting population growth is a vital part of any global strategy for averting the worst effects of global warming. In countless places around the world it has been shown that improving women’s education and giving easy access to family planning helps reduce the number of children in each family. As well as reducing fossil fuel use and minimising forest loss, we must therefore help women in poorer countries manage their own fertility.



A shorter version of this article appeared in the Sunday Times on 29 November 2009.