In “Brazil enjoys sugar power’s sweet success” (Financial Times, June 20, 2007),  Jonathan Wheatley observes that whereas Brazil will produce about 4.6 billion gallons of ethanol this year “using about half the 16 million hectares of land planted with sugar cane,” the U.S. will produce “4.9 billion gallons from 78 million hectares” of corn.

By my back of the envelope, those numbers mean that, per unit of land, Brazilian ethanol is about eight times more productive than U.S. ethanol.

The economics of ethanol production may increasingly favor Brazil as output increases, because whereas “land in the US is scarce, Brazil has enormous scope for expansion.”

So why aren’t Americans putting greener, cheaper Brazilian ethanol in their tanks? Because “a US ethanol tariff set at 54 cents a gallon means that Brazil’s biggest potential export market is all but out of reach.”