“Clean coal” is the hot issue in energy policy, firing up the passions of politicians, businesses and environmentalists. For its supporters, it is the answer to the problem of providing energy that is secure, affordable and non-polluting. For its opponents, it is a con, and “clean coal” is an oxymoron like “military intelligence”. But at the heart of the debate is often a simple failure to agree what the words mean.
The appeal of clean coal for countries such as the US, Germany and China is obvious. They have large domestic coal reserves that they rely on for large proportions of their electricity – 50 per cent in the US, 90 per cent in China – and that provide an energy source not dependent on imports from unreliable countries such as Russia or Venezuela. But coal is very dirty: both in its contribution to smog and acid rain, and more importantly, in its greenhouse gas emissions. If coal-rich countries want to find a way to join the fight against global warming, they need to curb those carbon dioxide emissions from their coal-fired power stations.
Enter clean coal. Its supporters, including president Obama and much of the electricity industry in the US and worldwide, say it offers a chance to secure energy supplies while cutting greenhouse gas emissions. Sceptics include some in the energy business, but the opposition is firecest from environmentalists, such as the protestors in Washington this week, and the Reality Coalition, which backed the recent video ad directed by the Coen brothers, which argues: “In reality, there’s no such thing as clean coal”.
The problem with the debate is that neither side is clear about what they mean when they say “clean coal”. (Although a conference call from Reality Coalition explaining the ad does go a little way into the details.)
Sometimes the words are used to mean “coal that produces less acid rain”, sometimes “coal that burns more efficiently”, sometimes “coal that could be emissions-free in the future” and sometimes “coal that has no environmental impacts whatsoever”.
For example, the US industry claims:
“Today’s coal-based electricity generating fleet is 70% cleaner than it was in 1970 (based upon emissions per unit of energy produced).”
But that refers to the emissions that cause acid rain and toxic air pollution, and has nothing to do with the central issue of carbon dioxide.
On the other side, the claim that “there’s no such thing as clean coal” ignores the fact that a coal-fired power station that captures and stores its carbon dioxide emissions is technically perfectly possible. All the constituent parts of the technology have been developed and put into use, and need only to be put together. Indeed one such project is already operational, albeit on a small scale. Obviously, the coal still needs to be mined and transported, and that will have environmental impacts, but the most useful definition of “clean coal” is “coal-fired power stations with carbon capture and storage”, and in that sense the term is certainly not an oxymoron.
A better line of attack for the environmentalists would be to focus on what is happening to efforts to develop carbon capture on a commercial scale. (The Vattenfall plant in Germany is very small indeed, described derisively as “a toy” by one competitor.) As Energy Source has been reporting, pilot projects for carbon capture have been running into difficulties from Abu Dhabi to Australia.
The biggest problem, still, is the cost. Coal-fired power stations with carbon capture and storage have been estimated as costing about twice as much as conventional coal plants, and the electricity as costing 50-100 per cent more. Until governments make it clear that they are prepared to pay those prices, clean coal will remain a possibility, but not a reality.
Footnote: the BBC has a great review of carbon capture technology to be found from here.