Fuel from Fruit

As gasoline prices continue to climb, people have started searching for a cheaper way to fill up their gas tank. Hybrid cars get all the press, but the newest rage might be fuel from orange and lemon peels.

Scientists for the USDA's Agricultural Research Service (ARS) have improved on the method for converting dried citrus peel waste in the ethanol fuel. Citrus waste is rich in pectin, cellulose, and polysaccharides, which can be turned into sugars and fermented into alcohol.

The work was started by ARS researchers in 1992, but was expensive and inefficient, working in batches of just a gallon or so. In 2004, ARS chemist Bill Widmer modified the technique to work on the 1,000-gallon level. The process now shows economic promise and a 10,000-gallon facility is currently under construction.

Florida alone creates a total of 1.2 million tons of dried peel residue annually, which is currently sold as cattle feed. With further research, Widmer said, Florida's citrus waste could yield up to 80 million gallons of ethanol per year.

--Bjorn Carey

Amazing Images: Science & Nature Photos from Our Readers

Tipping Point: Half of America Wants a Hybrid Car

The Mysterious Origin and Supply of Oil

Experimental Hybrid Cars Get Up to 250 Mpg

Ethanol Fuel More Advantageous Than Thought

Credit: Bill Widmer