Though the first hints of autumn are starting to appear in Pittsburgh weather, this past summer was a scorcher that saw increased natural gas power generation trying to keep air conditioners running.
That's the takeaway of the latest energy report from the U.S. Energy Information Administration, a federal agency that tracks what sources are used for power generation. Electrical suppliers can choose to use coal or natural gas for power generation, and increased gas drilling and infrastructure have recently tipped the playing field toward natural gas.
Natural gas use for power generation rose this year, averaging 26.3 billion cubic feet per day for the first 8.5 months of 2012, an increase of 24 percent from the same period last year.
Much of that increase was seen in the warm summer months, according to Bentek Energy, an energy analytics firm based in Evergreen, Colo.
Bentek measures "power burn," or the amount of natural gas used to generate power. The company told the EIA that 17 of the 25 highest days of power burn seen in the last seven years occurred this summer between June 28 and Aug. 9.
The Northeast market used about 6 billion cubic feet of natural gas per day, up 23 percent from last year.
Warm weather contributed to the need. The first half of 2012 was the warmest since 1985 in 28 states, according to the National Oceanic and Atmospheric Administration.
Other recent EIA reports have shown big increases in natural gas use and supply in power generation. Nationwide, proved reserves of natural gas increased by the biggest year-over-year margin in 2010 since the EIA began publishing estimates, the agency said last month.
Meanwhile, in April, natural gas supplied the same amount for power generation as coal -- also the first time that had happened since the agency began publishing estimates.
The jump in natural gas use coincides with recent EIA reports on coal's decreasing presence in the power generation sector.
About 9,000 megawatts of coal-fired capacity is expected to be retired by the end of this year, and low natural gas prices have been an extra incentive for companies that can switch between the two sources.
That has become a political touchstone in recent months, with Republican candidates trying to win over coal mining votes by bashing recent regulations and mandatory updates that they say cost jobs. Additional coal-fired plants are expected to be retired after this year, as well.