In a State of the Union address in February 2006, former US President George Bush pledged to end the nation's "addiction to oil", through increasing spending on renewable technologies. One such technology was ethanol, a fuel produced from agricultural feedstocks such as sugar cane, wheat and corn, and blended in small amounts with gasoline to power motor vehicles. Government incentives have caused this market to flourish over the past five years, particularly in the US, which is now the world's