Fuel Sources for U.S. Electrical Generation 2006
Power Plant	Total Number	Nameplate Capacity	Percent of	Nameplate Annual	Actual Annual	Actual Capacity	Percent of
by Fuel Type	of Installations	(MW)	Capacity	Generation (GWh)	Net Generation (GWh)	Factor	Net Generation
Coal	1,493	335,830	31.2	2,941,871	1,990,926	68	49.0
Natural Gas	5,470	442,945	41.2	3,880,198	813,044	21	20.0
Nuclear	104	105,585	9.8	924,925	787,219	85	19.4
Hydro	3,988	77,419	7.2	678,190	289,246	43	7.1
Renewables	1,823	26,470	2.5	231,877	96,423	42	2.4
Other*	4,046	87,426	8.1	765,852	87,843	11	2.2
Total	16,924	1,075,675	100.0	9,422,913	4,064,701	43	100
NOTES:
Nameplate Capacity is the maximum rate that the plants can produce.
Percent of Capacity is the percent of total nameplate capacity for that power plant type.
Nameplate Annual Generation is the theoretical total gigawatt-hours that could be generated running at the nameplate rate all year. Calculated as Nameplate Capacity multiplied by the numbers of hours in a year, 8,760. Actual production will always be less than this because no producer can run at the maximum rate all year.
Actual Net Generation is the actual gigawatt-hours (GWh) generated.
Percent of Net Generation is the percent of total generation for that power plant type.
Actual Capacity Factor is the actual generation as a percent of the Nameplate Annual Generation.
**Several smaller power plant types were combined to the 'other' line to simplify the results.
Source:
http://www.eia.doe.gov/cneaf/electricity/epa/epat1p1.html
http://www.eia.doe.gov/cneaf/electricity/epa/epat2p2.html