My Times column on carbon capture:
Carbon dioxide is not the most urgent problem facing humanity, compared with war, extremism, poverty and disease. But most presidents, popes and film stars think it is, so I must be wrong. For the purposes of this article let’s assume they are right. What’s the best way of solving the problem?
Whichever party wins the election will be legally committed to cutting our carbon dioxide emissions by 80 per cent by 2050. About 90 per cent of Britain’s total energy still comes from fossil fuels and bio-energy, both of which produce carbon dioxide. The expansion of nuclear, wind and solar is not going nearly fast enough, because electricity comprises just one third of our energy use. If we are to decarbonise transport and heating too, we will have to switch to electric cars, and electric radiators, which means generating three times as much electricity. Only aeroplanes would be left using fossil fuels.
Leave aside for now the problem of the intermittency of renewables: how to charge your car, or cook on your electric hob when the wind is not blowing and the sun is not shining. Also, the rest of the world is not following suit: fossil fuel use is growing rapidly and maintaining market share. The concentration of carbon dioxide in the atmosphere, as measured on a Hawaiian mountain top, is climbing relentlessly.
The science and technology committee of the House of Lords (on which I sit) told the government last week in a report on the resilience of the electricity system that it has not sufficiently informed the public about the “trilemma” facing policymakers. We cannot — in the present state of technology — make the electricity supply low-carbon, resilient and low-cost all at the same time. Decarbonisation is not achievable if politicians wish to restrain energy prices.
Which leaves plan B: to continue using fossil fuels but extract the carbon dioxide from power station exhaust by “carbon capture and storage” (CCS). The Energy Technology Institute told our committee that CCS is the only way to keep the cost of decarbonisation from raising energy prices by an extra £10 billion a year by 2030 and “several tens of billions a year” by 2050.
When the topic of CCS comes up, I admit to being unsure whom to believe. On the one hand there are those who say: it is ready to go, it solves the problem, what are we waiting for? On the other, those who say it’s a costly white elephant going nowhere.
My own self-interest as a landlord of a Northumbrian coal producer would suggest that I should be in the first category, because it’s a get-out-of-jail-free card for the fossil-fuel industry. If CCS were to work, then we could press ahead with fossil fuels and stop worrying. But I’m not convinced it will do the trick.
It is technically possible to extract CO2 from an exhaust stream. The recipe is as follows: bubble the exhaust gases through a caustic brew of chemicals called amines, which grab the CO2. Then place the brew back on the stove, bring the heat up to 120C and the CO2 fizzes back off again. Capture it and inject safely into an oil well to enhance the recovery of more oil, or store it underground. Save the caustic brew and re-use.
The first problem is that the process reduces the efficiency of the power station. A normal coal-fired power station runs at about 35 per cent efficiency — that is to say, a bit more than a third of the heat energy in the steam gets turned into electricity. Adding CCS means that the efficiency drops to maybe 26 per cent. The cost correspondingly goes up substantially, as do people’s electricity bills: according to the industry, it would roughly treble the price to about the same as power from an offshore wind farm.
The biggest working demonstration of CCS began operating last October in Saskatchewan in Canada, where SaskPower says its new coal-fired plant is exceeding expectations, generating about 160 megawatts, 40 of which are used to capture the carbon dioxide, leaving about 120 megawatts for the grid. The 2,300 tonnes a day of captured carbon dioxide are 99 per cent pure and are used to enhance recovery of oil near by. But this is a small unit by coal-fired power station standards and only pays because the nearby oil industry is prepared to buy the CO2.
Nor is it without risks, so the greens are against it, though they would be anyway because they hate the idea of fossil fuels getting a new lease of life. Injecting huge quantities of carbon dioxide into the ground risks causing small earthquakes, and possible leakage, with the (remote) potential to suffocate a nearby town.
The British government has been dangling a £1 billion carrot in front of the energy industry to get CCS going. A few years ago, Eon and Scottish Power both dropped out. Then last year two projects signed contracts, one in Yorkshire, and one in Peterhead in Scotland. In the latter case, SSE, the energy company, and Shell propose to pump the CO2 out under the North Sea, not to help to enhance the recovery of oil but to justify putting off the decommissioning of an oil platform called Goldeneye.
Similar delays and cancellations are affecting CCS around the world. Whereas the United Nations once forecast that at least 20 large-scale demonstration plants would be on line by 2020, in practice there will be none. Given that electricity is only a small part of the energy system, if CCS is to solve our problems it has to roll out to not just every coal and gas power station on the planet, but to three times as many — once we have electrified heat and transport.
However, all is not lost. Last week scientists at the University of California, Berkeley, announced the discovery of a new class of compounds that scrub carbon dioxide from exhaust much more cheaply. Called diamine-appended metal-organic-frameworks, they require only half as much heating as the conventional process. Another team at Lawrence Livermore Laboratory, also in California, is getting good results with microcapsules of baking soda. In other words, it is possible that chemists will come up with something much cheaper — but it will take time to find out if such ideas can be scaled up efficiently.
For now, though, there is no way to meet our self-imposed decarbonisation target without bankrupting the country. It’s not more effort and political will we need; it’s more research.
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