The production and use of non-hydropower renewable energy sources were up in recent years. Wind and biofuels consumption (the dark blue and red bars) increased about 16 times and 8 times, respectively, between 2000 and 2010. Overall consumption of renewable energy, including hydropower, represented about 8% of total energy consumption in the United States in 2010.
Wind: Electricity generation from wind increased from about 6 billion kilowatthours in 2000 to about 95 billion kilowatthours in 2010. Improved technology has decreased the cost of producing electricity from wind. In addition, several policies contributed to growth in wind power:
Biofuels: Biofuels such as ethanol and biodiesel are transportation fuels derived from biomass materials. Fuel ethanol from corn is the primary biofuel used in the United States. Biofuels are usually blended with petroleum fuels, such as gasoline and diesel fuel, but they can also be used on their own.
In 2010, Americans consumed about 13 billion gallons of fuel ethanol, compared to less than 2 billion gallons in 2000. About 99% of this fuel ethanol was added to gasoline in mixtures up to 10% ethanol and 90% gasoline. Nearly all gasoline sold in the United States contains some ethanol.
Federal and state requirements and incentives encouraging the production and use of biofuels include:
Biomass—biofuels, wood, and organic waste—is the largest single source of renewable fuel in the United States. However, when the types of biomass are considered as separate categories, hydroelectric power generation is the largest source of renewable energy. Hydroelectric generation increases in some years and decreases in others, primarily due to variation in the amounts of rainfall and snowfall in areas where major hydroelectric dams are located.