If there was ever a way to neatly sum up 80 years of energy policy, economics and technology in the United States, this chart might do the trick.
The U.S. Energy Information Administration looked at all power plants in operation, as of 2010, and then charted them out by the date they came online and fuel type (hat tip Andrew Revkin at NYT). The chart tells dozens of stories: the early reliance on hydropower; the long-standing dominance of coal; and the wave of nuclear plant construction from the late 1960s to about 1990.
Then there's the more recent and dramatic shift from coal to natural gas power plants. Most gas-fired capacity is less than 10 years old, the EIA said. Meanwhile, 73 percent of all coal-fired capacity was 30 years or older at the end of 2010.
The rise of natural gas has been thoroughly documented in recent years. And while wind power has seen its fair share of press coverage, folks might not realize just how far its come within the U.S. power sector. Since 2006, 36 percent of total electric power industry capacity additions have been wind generators, the EIA said.
This recent wave of natural gas-fired and wind generating capacity additions shows no signs of slowing.
In the first half of 2012, 165 new electric power generators were added in 33 states, for a total of 8,098 megawatts of new capacity, the EIA said in a brief released Monday. Ten states, which added 80 percent of that new generating capacity, turned primarily to natural gas and renewable energy.
More small generators were added than large generators, the EIA said. Of the 165 generators added, 105 were under 25 MW and many of these use renewable energy sources, most commonly solar and landfill gas.
Efficient combined cycle natural gas generators are now competitive with coal generators over large parts of the country and are increasingly moving into coal country. For example, combined-cycle generators that came online in the first six months of 2012 were added in states that traditionally burn coal, with the exception of Idaho, the EIA said.
As existing coal plants continue to age, few, if any, will take their place in the coming years. Only one coal-fired generator, an 800-MW unit in Illinois, was brought online in the first half of 2012. Fourteen of the planned coal generators in EIA databases are in the construction phase. An additional five are reporting a planned status, but are not yet under construction. The EIA noted that only one of the 14 advanced from a pre-construction to an under-construction status between its 2010 and 2011 surveys.