<P> The largest gas producing states in 2007 were Texas (30%), Wyoming (10%), Oklahoma (9%) and New Mexico (8%), while 14% of the country's production came from the federal offshore lands in the Gulf of Mexico . Recent development in hydraulic fracturing and horizontal drilling have increased interest for shale gas across the United States in recent years . Leading fields are the Barnett Shale in Texas and the Antrim Shale in Michigan . Natural gas reserves in the United States were 35% higher in 2008 than two years earlier largely due to shale gas discoveries . </P> <P> The United States is the world's largest supplier of commercial nuclear power . As of 2010, the demand for nuclear power is softening in America, and some companies have withdrawn their applications for licenses to build . Ground has been broken on two new nuclear plants with a total of four reactors . The only reactor currently under construction in America, at Watts Bar, Tennessee, was begun in 1973 and may be completed in 2012 . Of the 104 reactors now operating in the U.S., ground was broken on all of them in 1974 or earlier . In September 2010, Matthew Wald from the New York Times reported that "the nuclear renaissance is looking small and slow at the moment". </P> <P> In August 2011, John Rowe, head of Exelon, America's largest nuclear utility, said that this was not the time to build new nuclear plants, not because of political opposition or the threat of cost overruns, but because of the low price of natural gas . "Shale (gas)", said he, "is good for the country, bad for new nuclear development". </P> <P> Following the 2011 Japanese nuclear accidents, the U.S. Nuclear Regulatory Commission has announced it will launch a comprehensive safety review of the 104 nuclear power reactors across the United States, at the request of President Obama . The Obama administration "continues to support the expansion of nuclear power in the United States, despite the crisis in Japan". Following the Japanese nuclear emergency, public support for building nuclear power plants in the U.S. dropped to 43%, slightly lower than it was immediately after the Three Mile Island accident in 1979, according to a CBS News poll . </P>

History of u.s. energy policies over the 20th and 21st centuries