Bio fuels produced by converting food crops into ethanol are facing heavy criticism for fueling the global food crisis. But there are bio fuels that are both, friendly to the environment and no competition for food supplies. These biofuels are made of waste and leftovers of agricultural production such as straw, matured timber and orange peels.
Florida is the second largest producer next to Brazil of oranges in the world with more than 300,000 hectares of orange acreage. About 10 million tons of oranges are processed into juice in Florida alone annually. Until today, the leftovers have been used to make dry pallets as cattle feed, but this is an expensive and barely profitable process.
Karel Grohmann, a researcher and chemist at the State Department for Agriculture has found an alternative to making cattle feed or dumping the leftovers into landfills.
Grohmann’s team uses enzymes and a strain of bacterium to convert the sugars, of which the citrus waste consists mostly, to ethanol and essential oil amongst others. A pilot project has been running for two years now and it shows that converting 100 liters of orange peel waste mash into 4 liters of ethanol is profitable. It is estimated that the 5 million tons of annual waste from orange processing in Florida could be converted into some 230 million liters of ethanol.
This ethanol could be used to fuel the more than six million Flexible Fuel Cars which are on the road in the US today. Ethanol made from waste is the best alternative to ethanol made of food crops and the most sensible processing of the leftovers of orange juice production which would mostly be rotting in landfills otherwise.