Coal's share of total U.S. electricity generation falls below 40% in November and December

Although still the largest single fuel for electricity generation, coal's share of monthly power generation in the United States dropped below 40% in November and December 2011. The last time coal's share of total generation was below 40% for a monthly total was March 1978. A combination of mild weather (leading to a drop in total generation) and the increasing price competitiveness of natural gas relative to coal contributed to the drop in coal's share of total generation.

Natural gas prices have dropped significantly this winter, leading the generators in some states (such as Ohio and Pennsylvania) to significantly increase the share of natural gas-fired generation. Natural gas combined-cycle units operate at higher efficiency than do older, coal-fired units, which increases the competitiveness of natural gas relative to coal.

Total electricity generation was down 7% in December 2011 compared to December 2010 (see chart below). Despite this decline, generation from natural gas rose 12% to 86 terawatthours. Coal-fired generation, however, fell by 21% between December 2010 and December 2011, to 132 terawatthours.

EIA recently released preliminary data through December 2011 on generation, fuel consumption, and other statistics from the electric power industry in the Electric Power Monthly and Electricity Monthly Update.