Biofuels hurt poor and environment

There are always unintended consequences. Always.

It doesn't get madder than this. Swaziland is in the grip of a famine and receiving emergency food aid. Forty per cent of its people are facing acute food shortages. So what has the government decided to export? Biofuel made from one of its staple crops, cassava. The government has allocated several thousand hectares of farmland to ethanol production in the district of Lavumisa, which happens to be the place worst hit by drought. It would surely be quicker and more humane to refine the Swazi people and put them in our tanks. Doubtless a team of development consultants is already doing the sums.

And it actually makes things worse.

The law the British government passed a fortnight ago - by 2010, 5% of our road transport fuel must come from crops - will, it claims, save between 700,000 and 800,000 tonnes of carbon a year. It derives this figure by framing the question carefully. If you count only the immediate carbon costs of planting and processing biofuels, they appear to reduce greenhouse gases. When you look at the total impacts, you find they cause more warming than petroleum.

A recent study by the Nobel laureate Paul Crutzen shows that the official estimates have ignored the contribution of nitrogen fertilisers. They generate a greenhouse gas - nitrous oxide - that is 296 times as powerful as CO2. These emissions alone ensure that ethanol from maize causes between 0.9 and 1.5 times as much warming as petrol, while rapeseed oil (the source of more than 80% of the world's biodiesel) generates 1-1.7 times the impact of diesel. This is before you account for the changes in land use.