The following is a reference taken from the signing of the Energy Policy Act by President George W. Bush:

"The bill also will lead to a greater diversity of fuels for cars and trucks. The bill includes tax incentives for producers of ethanol and biodiesel. The bill includes a flexible, cost-effective renewable fuel standard that will double the amount of ethanol and biodiesel in our fuel supply over the next seven years. Using ethanol and biodiesel will leave our air cleaner. And every time we use a home-grown fuel, particularly these, we're going to be helping our farmers, and at the same time, be less dependent on foreign sources of energy."

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