The United States is the largest energy consumer in terms of total use, using 100 quadrillion BTUs (105 exajoules, or 29 PWh) in 2005. This is three times the consumption by the United States in 1950. The U.S. ranks seventh in energy consumption per-capita after Canada and a number of small countries.
The vast majority of this energy is derived from fossil fuels: in 2005, it was estimated that 40% of the nation's energy came from petroleum, 23% from coal, and 23% from natural gas. Nuclear power supplied 8.4% and renewable energy supplied 7.3%, which was mainly from hydroelectric dams although other renewables are included such as wind power, geothermal and solar energy.Energy consumption has increased at a faster rate than energy production over the last fifty years in the U.S.(when they were roughly equal). This difference is now largely met through imports.
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 335.9 million BTUs per person from 1980 to 2006. 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 72.4 million BTU's per person in 2006. On the other hand, US "off-shoring" of manufacturing is sometimes exaggerated: US domestic manufacturing has grown by 50% since 1980.
The development of renewable energy and energy efficiency marks "a new era of energy exploration" in the United States, according to President Barack Obama.
History
US energy consumption, by source, 1850-2000. Vertical axis is in quadrillion BTU
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 7 decades, but by 1950, it was surpassed in turn by both petroleum and natural gas. While coal consumption today is the highest it has ever been, it is now mostly used to generate electricity. 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 dramatically during this period, by approximately a factor of 50 between 1850 and 2000, energy use per capita increased only by a factor of 4.
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.Oil's unique qualities for transportation fuels in terms of energy content, cost of production, and speed of refueling have made it difficult to supplant with technological alternatives developed so far.
In June 2010, the American Energy Innovation Council, (which includes Bill Gates, Microsoft; Jeffrey R. Immelt, chief executive of General Electric; and John Doerr) 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.
Current consumption
U.S. Energy Flow - 2009. A quad is 1015 BTU, or 1.055 × 1018 joules. Note that the breakdown of useful and waste energy in each sector (yellow vs. grey) may be misleading because much of the 'lost' energy consists of unavoidable losses arising from the Second Law of thermodynamics: heat engines cannot convert 100% of thermal energy into useful work, and must dump a fraction of waste heat into the environment.
The U.S. Department of Energy tracks national energy consumption in four broad sectors: industrial, transportation, residential, and commercial. The industrial sector has long been the country's largest energy user, currently representing about 33% of the total. Next in importance is the transportation sector, followed by the residential and commercial sectors.
| Sector Name | Description | Major uses |
|---|---|---|
| Industrial | Facilities and equipment used for producing and processing goods. | 22% chemical production 16% petroleum refining 14% metal smelting/refining |
| Transportation | Vehicles which transport people/goods on ground, air or water. | 61% gasoline fuel 21% diesel fuel 12% aviation |
| Residential | Living quarters for private households. | 32% space heating 13% water heating 12% lighting 11% air conditioning 8% refrigeration 5% electronics 5% wet-clean (mostly clothes dryers) |
| Commercial | Service-providing facilities and equipment (businesses, government, other institutions). | 25% lighting 13% heating 11% cooling 6% refrigeration 6% water heating 6% ventilation 6% electronics |
The breakdown of energy consumption by source is given here:
| Fuel type | 2006 US consumption in PWh | 2006 World consumption in PWh |
| Oil | 11.71 | 50.33 |
| Gas | 6.50 | 31.65 |
| Coal | 6.60 | 37.38 |
| Hydroelectric | 0.84 | 8.71 |
| Nuclear | 2.41 | 8.14 |
| Geothermal, wind, solar, wood, waste | 0.95 | 1.38 |
| Total | 29.26 | 138.41 |
U.S, Primary Energy Consumption by Source and Sector in 2008 is tabled as following:
| Supply Sources | Percent of Source | Demand Sectors | Percent of Sector |
|---|---|---|---|
| Petroleum 37.1% | 71% Transportation 23% Industrial 5% Residential and Commercial 1% Electric Power | Transportation 27.8% | 95% Petroleum 2% Natural Gas 3% Renewable Energy |
| Natural Gas 23.8% | 3% Transportation 34% Industrial 34% Residential and Commercial 29% Electric Power | Industrial 20.6% | 42% Petroleum 40% Natural Gas 9% Coal 10% Renewable Energy |
| Coal 22.5% | 8% Industrial <1% Residential and Commercial 91% Electric Power | Residential and Commercial 10.8% | 16% Petroleum 76% Natural Gas 1% Coal 1% Renewable Energy |
| Renewable Energy 7.3% | 11% Transportation 28% Industrial 10% Residential and Commercial 51% Electric Power | Electric Power 40.1% | 1% Petroleum 17% Natural Gas 51% Coal 9% Renewable Energy 21% Nuclear Electric Power |
| Nuclear Electric Power 8.5% | 100% Electric Power |
Note: Sum of components may not equal 100 percent due to independent rounding.
Total Primary Consumption Historical Evolution in U.S until 2009.
Total Consumption until 2009 in Mtoe :
| 1990 | 1991 | 1992 | 1993 | 1994 | 1995 | 1996 | 1997 | 1998 | 1999 | 2000 | 2001 | 2002 | 2003 | 2004 | 2005 | 2006 | 2007 | 2008 | 2009 | 2008-2009 | CAGR 2000-09 |
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
| 1914 | 1929,6 | 1967,5 | 2000,9 | 2041,3 | 2067,3 | 2118,4 | 2140,7 | 2167,2 | 2215,9 | 2279,6 | 2235,8 | 2270,6 | 2265,2 | 2311 | 2324,6 | 2304,5 | 2340,4 | 2301,4 | 2201,4 | -4,3% | 0,4% |
CAGR = Compound Annual Growth Rate Note: Total energy includes coal, gas, oil, electricity, heat and biomass.
Regional variation
Average annual residential electricity usage by city, 2000-2005. Measured in Kilowatt hours per customer.
Household energy use varies significantly across the United States. An average home in the Pacific region (consisting of California, Oregon, and Washington) consumes 35% less energy than a home in the South Central region. Most of the regional differences can be explained by climate. The heavily populated coastal areas of the Pacific states experience generally mild winters and summers, reducing the need for both home heating and air conditioning. The warm, humid climates of the South Central and South Atlantic regions lead to higher electricity usage, while the cold winters experienced in the Northeast and North Central regions result in much higher consumption of natural gas and heating oil.
Another reason for regional differences is the variety of building codes and environmental regulations found at the local and state level. California has some of the strictest environmental laws and building codes in the country, which may contribute to the fact that its per-household energy consumption is lower than all other states except Hawaii.
Major U.S. cities also show significant variation in per capita energy consumption. In addition to differences in regional climates and variations in building code standards, factors affecting energy use in cities include population density and building design. Townhouses are more energy efficient than single-family homes because less heat, for example, is wasted per person.
Oil consumption
U.S. oil consumption is approximately 21,000,000 barrels per day (3,300,000 m3/d), yet domestic production is only 6 million barrels per day (950,000 m3/d). Hence, the majority of oil consumed in the United States must be imported. The cost to import oil is approximately $410 billion dollars a year (at $75/barrel).
During the Carter administration, in response to an energy crisis and hostile Iranian and Soviet Union relations, President Jimmy Carter announced the Carter Doctrine which declared that any interference with U. S. interests in the Persian Gulf would be considered an attack on U.S. vital interests.This doctrine was expanded by Ronald Reagan.
Today, many scholars and politicians call for the immediate incubation of long term energy solutions prior to a 'peak oil' scenario which would force the economy to grinding halt. Although additional drilling in areas such as continental shelf, the Gulf of Mexico, off the U.S. West Coast, Alaska, and the Great Lakes may stave off the inevitability of the problem, it would be only a temporary solution.
Electricity production
Electricity production by source.
coal, oil, natural gas
hydroelectric
nuclear
Other renewables
Further information: Electricity sector of the United States
That United States has and continues to get most of its electrical production from conventional thermal power plants. Most of these are coal; however, the 1990s and 2000s have seen a disproportionate increase in natural gas and other kinds of gas powered plants.
From 1992 to 2005 some 270,000 MWe (Megawatt electric) of new gas-fired plant were built, but only 14,000 MWe of new nuclear and coal-fired capacity came on line, mostly coal, with 2,315 MWe of that being nuclear.[19] Nuclear and coal are considerably more capital intensive when compared to gas, and the great shift to gas plant construction is often attributed to deregulation and other political and economic factors.
As of January 2008 the American Wind Energy Association estimated that U.S. wind power, capacity as 16,818 MW, sufficient to power 4.5 million homes. The largest wind facility in the U.S. and the world is in Roscoe Texas, costing more than $1 billion and providing 781.5 MW of power (enough for 230,000 homes throughout Texas, which has more wind power generation capacity than any other state and all but four countries.).Several solar thermal power stations, including the new 64 MW Nevada Solar One, have also been built. The largest of these solar thermal power stations is the SEGS group of plants in the Mojave Desert with a total generating capacity of 354 MW, making the system the largest solar plant of any kind in the world.
In 2007, summer demand for electricity was 783 GW and 640 GW for winter. By 2017, North American Electric Reliability Corporation (NERC) projects summer consumption to be 925GW for summer and 756 GW for winter.
Energy consumption of computers in the USA
Green computing
Visible or embedded (i. e. hidden) computers are found everywhere: in all sectors listed in the above chapter, as well as in all subsectors listed in the column entitled Major uses in the above tables. In 1999, a study by Mark. P. Mills [26] of the Green Earth Society reported that computers consumed 13% of the entire US supply. Numerous researchers questioned Mills' methodology and it was later demonstrated that he was off by an order of magnitude; for example, Lawrence Berkeley Labs concluded that the figure was nearer three percent of US electricity use. Although the Mills study was inaccurate, it helped drive the debate to the national level, and in 2006 the US Senate started a study of the energy consumption of Server farms.
International Cooperation
President Barack Obama and China's President Hu Jintao announced on 2009-11-17 a far-reaching package of measures to strengthen cooperation between the United States and China on clean energy. The presidents began by establishing a U.S.-China Clean Energy Research Center to facilitate joint research and development of renewable energy technologies by scientists from both countries. The center will be supported by $150 million in public and private funds over the next five years, split evenly between the partners. Initial research priorities will be building energy efficiency and electric vehicles.
The two countries will also leverage private sector resources to develop clean energy projects in China through the U.S.-China Energy Cooperation Program (ECP). More than 22 companies are founding members of the program. The ECP will include collaborative projects involving renewable energy, smart grids, electric vehicles, green buildings, combined heat and power and energy efficiency.
(source:wikipedia)