Thus far the star of this new science has been ethanol, a car fuel made from corn, but around the world chemical, grain and biotech companies are working to produce auto paint, cosmetics, even apparel fiber from renewable resources.

FORBES: Magazine Article

Watkins says the rest of his fortune lies in ethanol, a fuel additive usually made from corn.

FORBES: Show Me the Money

This type of ethanol refers to fuel made from waste, wood, plants and other products, as opposed to the now widely produced corn ethanol.

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Some have even calculated a ratio less than one, meaning it takes more energy to produce ethanol from corn than the energy content of the fuel.

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Unlike the U.S., ethanol is made from sugar cane rather than corn, and the growing use of sugar as a fuel in Brazil and other countries in recent years helped drive the price of the commodity.

FORBES: Big Oil Bets On Ethanol Too