Economist tviler på karbonfangst og lagring: “For the moment, at least, CCS is mostly hot air.”

I en ny artikkel hos Economist uttrykkes skepsis overfor karbonfangst og lagring:

Despite all this enthusiasm, however, there is not a single big power plant using CCS anywhere in the world. Utilities refuse to build any, since the technology is expensive and unproven. Advocates insist that the price will come down with time and experience, but it is hard to say by how much, or who should bear the extra cost in the meantime. Green pressure groups worry that captured carbon will eventually leak. In short, the world’s leaders are counting on a fix for climate change that is at best uncertain and at worst unworkable.

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Estimates of the total cost vary widely. America’s government, which had vowed to build a prototype plant called FutureGen in partnership with several big resources firms, scrapped the project last year after the projected cost rose to $1.8 billion. Philippe Paelinck, of Alstom, an engineering firm that hopes to build CCS plants, thinks a full-scale one would cost about €1 billion ($1.3 billion).

In 2005 the Intergovernmental Panel on Climate Change, a group of scientists that advises the United Nations on global warming, came up with a range of $14-91 for each tonne of emissions avoided through CCS. Last year, the IEA suggested that the price for the first big plants would be $40-90. McKinsey, a consultancy, has arrived at an estimate of €60-90, or $75-115.

Either way, that is more than the price of emissions in the European Union: about €10 a tonne. America does not have a carbon price at all yet. A bill defeated last year in the Senate would have yielded a carbon price as low as $30 in 2020, according to an official analysis. So CCS might not be financially worthwhile for years to come.

But these estimates entail some generous assumptions. McKinsey, for example, imagines that CCS plants will break down no more often than normal coal plants, despite their more complicated machinery. It assumes that the average cost of capital for CCS plants will be no more than 8%. And it projects that costs will fall by 12% for every doubling in capacity. That is roughly the same rate as for wind power, even though most of the processes in CCS are already widely used in other industries, suggesting that the scope for improvement is slender.

Analysts assume that the price of emissions will rise, as governments impose tighter restrictions, and that the price of CCS will fall, as engineers learn how to do it more cheaply. The IEA, for example, predicts CCS will cost just $35-60 per tonne of emissions reductions by 2030. McKinsey foresees a price of €30-45 when the technology is mature, some time after 2030.