By Martin Wolf

Energy security and climate change are two of the most significant challenges confronting humanity. What we see, in response, is the familiar capture of policymaking by well-organised special interests. A superb example is the flood of subsidies for biofuels. These are farm programmes masquerading as answers to energy insecurity and climate change. Not surprisingly, they have the depressing characteristics of such programmes: high protection, open-ended support to producers, and indifference to economic rationality.

Already the support in members of the Organisation for Economic Co-operation and Development costs about $13bn to $15bn a year. But this sum generates much less than 3 per cent of the overall supply of liquid transport fuel. To bring the biofuel share to 30 per cent, as some propose, would cost at least $150bn a year and probably more, as marginal costs rose.

Someone needed to take a close look at the rationality of all these supports. An excellent report from the Global Subsidies Initiative of the International Institute for Sustainable Development does just that. It does not tell a pretty story.

The remainder of this column can be read here. Debate from our guest economists appears below.