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The United States is the 2nd largest energy consumer (after China) in terms of total use in 2010. The U.S. ranks seventh in energy consumption per-capita after Canada and a number of small nations.〔(World Per Capita Total Primary Energy Consumption,1980-2005 ) (MS Excel format)〕〔World Resources Institute "(Energy Consumption: Consumption per capita )" (2001). Nations with higher per-capita consumption are: Qatar, Iceland, United Arab Emirates, Bahrain, Luxembourg and Canada. Except for Canada, these are small countries with a prominent energy-intensive industry such as oil refining or steelmaking.〕 Not included is the significant amount of energy used overseas in the production of retail and industrial goods consumed in the U.S. The majority of this energy is derived from fossil fuels: in 2010, data showed 25% of the nation's energy came from petroleum, 22% from coal, and 22% from natural gas. Nuclear power supplied 8.4% and renewable energy supplied 8%,〔See #Fossil-fuel equivalency - these figures are actually closer to 2.8% each.〕 which was mainly from hydroelectric dams and biomass but also included other renewable sources such as wind power, geothermal and solar energy.〔US Dept. of Energy, "(Annual Energy Report )" (2010), Energy Flow diagram〕 Energy consumption has increased at a faster rate than domestic energy production over the last fifty years in the U.S. (when they were roughly equal). This difference is now largely met through imports.〔Ristinen, Robert, A. Energy and the Environment. Malloy, 2006. Print.〕 According to the Energy Information Administration's statistics, the per-capita energy consumption in the US has been somewhat consistent from the 1970s to today. The average has been 334 million British thermal units (BTUs) per person from 1980 to 2010. One explanation suggested for this is that the energy required to produce the increase in US consumption of manufactured equipment, cars, and other goods has been shifted to other countries producing and transporting those goods to the US with a corresponding shift of green house gases and pollution. In comparison, the world average has increased from 63.7 in 1980 to 75 million BTU's per person in 2008. On the other hand, US "off-shoring" of manufacturing is sometimes exaggerated: US domestic manufacturing has grown by 50% since 1980. ==History== From its founding until the late 18th century, the United States was a largely agrarian country with abundant forests. During this period, energy consumption overwhelmingly focused on readily available firewood. Rapid industrialization of the economy, urbanization, and the growth of railroads led to increased use of coal, and by 1885 it had eclipsed wood as the nation's primary energy source. Coal remained dominant for the next seven decades, but by 1950, it was surpassed in turn by both petroleum and natural gas. In 2007, coal consumption was the highest it has ever been, with coal mostly being used to generate electricity.〔(Annual Coal Report )〕 Natural gas, which is cleaner-burning and more easily transportable, has replaced coal as the preferred source of heating in homes, businesses and industrial furnaces. Although total energy use increased by approximately a factor of 50 between 1850 and 2000, energy use per capita increased only by a factor of four. As of 2009, United States per capita energy use had declined to 7075 (kilograms of oil-equivalent), 12% less than 2000, and through 2010 (most recent available) is at levels not seen since 1960s usage levels.〔(【引用サイトリンク】title=World Development Indicators - Google Public Data Explorer )〕 At the beginning of the 20th century, petroleum was a minor resource used to manufacture lubricants and fuel for kerosene and oil lamps. One hundred years later it had become the preeminent energy source for the U.S. and the rest of the world. This rise closely paralleled the emergence of the automobile as a major force in American culture and the economy. While petroleum is also used as a source for plastics and other chemicals, and powers various industrial processes, today two-thirds of oil consumption in the U.S. is in the form of its derived transportation fuels.〔US Dept. of Energy, "(Energy in the United States: 1635-2000 )"〕 Oil's unique qualities for transportation fuels in terms of energy content, cost of production, and speed of refueling all contributed to it being used over other fuels. In June 2010, the American Energy Innovation Council, a group which includes Bill Gates, of Microsoft; Jeffrey R. Immelt, chief executive of General Electric; and John Doerr,〔(【引用サイトリンク】 publisher=American Energy Innovation Council )〕 has urged the government to more than triple spending on energy research and development, to $16 billion a year. Mr. Gates endorsed the administration's goal of reducing greenhouse gas emissions by 80 percent by 2050, but said that was not possible with today's technology or politicism. He said that the only way to find such disruptive new technology was to pour large sums of money at the problem. The group notes that the federal government spends less than $5 billion a year on energy research and development, not counting one-time stimulus projects. About $30 billion is spent annually on health research and more than $80 billion on military R.& D. They advocate a jump in spending on basic energy research. US CO2 emissions have dropped about 1% per year through greater efficiency and a sluggish economy since 2008. 抄文引用元・出典: フリー百科事典『 ウィキペディア（Wikipedia）』 ■ウィキペディアで「Energy in the United States」の詳細全文を読む スポンサード リンク
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