IamTheRealMike writes "Vinod Khosla, venture capitalist and co-founder of Sun, has a new obsession these days. Ethanol is the fuel touted by many as an alternative to dwindling oil stocks, but is it all it's cracked up to be? Whilst Khosla is an avid supporter of ethanol as an alternative fuel (video link) his optimistic views have been rigourously challenged by Robert Rapier, an oil industry insider who is also engaged in a quest to discover alternatives. Recently the two debated via phone the merits of an ethanol economy, and Mr Rapier has now written up a report of the debate. What will be powering our cars 10 years from now?"