Table 4.3. Existing Capacity by Energy Source, 2012 (Megawatts)

Energy Source Number of Generators Generator Nameplate Capacity Net Summer Capacity Net Winter Capacity
Coal 1,309 336,341 309,680 312,293
Petroleum 3,702 53,789 47,167 51,239
Natural Gas 5,726 485,957 422,364 455,214
Other Gases 94 2,253 1,946 1,933
Nuclear 104 107,938 101,885 104,182
Hydroelectric Conventional 4,023 78,241 78,738 78,215
Wind 947 59,629 59,075 59,082
Solar Thermal and Photovoltaic 553 3,215 3,170 3,053
Wood and Wood-Derived Fuels 351 8,520 7,508 7,570
Geothermal 197 3,724 2,592 2,782
Other Biomass 1,766 5,527 4,811 4,885
Hydroelectric Pumped Storage 156 20,858 22,368 22,271
Other Energy Sources 95 2,005 1,729 1,739
Total 19,023 1,167,995 1,063,033 1,104,459

Notes: Coal includes anthracite, bituminous, subbituminous, lignite, and waste coal; coal synfuel and refined coal; and beginning in 2011, coal-derived synthesis gas. Prior to 2011, coal-derived synthesis gas was included in Other Gases.
Petroleum includes distillate fuel oil (all diesel and No. 1, No. 2, and No. 4 fuel oils), residual fuel oil (No. 5 and No. 6 fuel oils and bunker C fuel oil), jet fuel, kerosene, petroleum coke (converted to liquid petroleum, see Technical Notes for conversion methodology), waste oil, and beginning in 2011, synthetic gas and propane. Prior to 2011, synthetic gas and propane were included in Other Gases.
Other Gases includes blast furnace gas. Prior to 2011, waste heat was included in Natural Gas.
Hydroelectric Conventional capacity includes conventional hydroelectric power excluding pumped storage facilities.
Wood and wood-derived fuels include wood/wood waste solids (including paper pellets, railroad ties, utility poles, wood chips, bark, and wood waste solids), wood waste liquids (red liquor, sludge wood, spent sulfite liquor, and other wood-based liquids), and black liquor.
Other Biomass include municipal solid waste, landfill gas, sludge waste, agricultural byproducts, other biomass solids, other biomass liquids, and other biomass gases (including digester gases, methane, and other biomass gases).
Hydroelectric Conventional capacity includes conventional hydroelectric power excluding pumped storage facilities.
Other Energy Sources include batteries, hydrogen, purchased steam, sulfur, tire-derived fuels and other miscellaneous energy sources.
Capacity by energy source is based on the capacity associated with the energy source reported as the most predominant (primary) one, where more than one energy source is associated with a generator.
In 2011, EIA corrected the NAICS codes of several plants which resulted in a net capacity shift from the electric utility sector to the commercial sector.
Source: U.S. Energy Information Administration, Form EIA-860, 'Annual Electric Generator Report.'