Report: Renewable Energy Accounts for Capacity Increase

For the first time, non-hydroelectric renewable energy, led by wind power, was the leading source of new electric generating capacity in the United States, according to "Electric Power Annual 2007" from the U.S. Energy Information Administration.

The study found that in 2007, electric power generation increased 2.3 percent, from 4,065 million megawatt-hours (MWh) in 2006 to 4,157 MWh in 2007. Total net summer capacity increased 8,673 MW. Wind capacity accounted for 5,186 MW of this new capacity.

Net generation produced by renewable energy sources, excluding hydroelectric generation, grew by 9.0 percent as compared to 10.5 percent growth in 2006. Renewable energy accounted for 2.5 percent or 105 million MWh of total net generation in 2007. This marks the fourth consecutive year in which renewables' share of total net generation has increased.

In 2007, wood and wood-derived fuels accounted for 39 million MWh or 0.9 percent of total net generation. These fuels continued to be the largest sources of renewable generation, accounting for 37.1 percent of total net renewable generation, excluding conventional hydroelectric generation.

Wood and wood-derived fuels have maintained fairly stable output levels averaging 38 million MWh per year.

Other biomass supplied 17 million MWh of net generation. It has declined from a 23 million MWh peak in 2000 to 17 million MWh in 2007.

Wind generation was the second largest renewable energy source, contributing 34 million MWh or 0.8 percent of total net generation in 2007. It is rapidly gaining a larger share of total renewable generation. In 2007, wind accounted for 32.7 percent of total net generation from non-hydroelectric renewable sources, as compared to 4.3 percent in 1997.

The annual growth in solar thermal and photovoltaic generation has been sufficient for this renewable source to account, on average, for 0.5 percent of all non-hydroelectric renewable energy.

Geothermal power plants contributed 15 million MWh of net generation and accounted for approximately 0.4 percent of total net generation in 2007. Geothermal has maintained fairly stable output levels averaging 15 MWh per year.

Conventional hydroelectric power continues to decline as a share of total net generation. It declined 14.4 percent from 289 million MWh in 2006 to 248 million MWh in 2007. In 2007, conventional hydroelectric generating capacity accounted for 6.0 percent of total net generation, as compared to 10.2 percent in 1997.

The decline in conventional hydroelectric generation is consistent with drought conditions, which, according to the National Climatic Data Center (NCDC), prevailed over the West and Southeast for much of the year. According to NCDC, evaporation caused by above-normal summer temperatures exacerbated drought conditions. Moreover, precipitation was below average in the Southeast, and the mountain snowpack in the Rocky Mountain and Western States was significantly below normal levels.

"Electric Power Annual 2007" was issued on Jan. 21, and can be found online at