The United States used significantly less coal and petroleum in 2009 than in 2008, and significantly more wind power. There also was a decline in natural gas use and increases in solar, hydro and geothermal power according to the most recent energy flow charts released by the Lawrence Livermore National Laboratory.
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| The left side of the chart shows the different sources of energy and the amounts produced. Following the flow of energy from left to right, the pink boxes show where the energy is consumed (electrical generation, residential, commercial, industrial and transportation) while the shades of gray show the amount of energy lost or rejected – often through heat loss. The information is based on DOE/EIA-0384(2009), August 2010. Distributed electricity represents only retail electricity sales and does not include self-generation. EIA reports flows for non-thermal resources (i.e., hydro, wind and solar) in BTU-equivalent values by assuming a typical fossil fuel plant “heat rate.” End use efficiency is estimated as 80% for the residential, commercial and industrial sectors, and as 25% for the transportation sector. |
The estimated U.S. energy use in 2009 equaled 94.6 quadrillion BTUs (“quads”), down from 99.2 quadrillion BTUs in 2008. (A BTU or British Thermal Unit is a unit of measurement for energy, and is equivalent to about 1.055 kilojoules). The average American household uses about 95 million BTU per year.
Energy use in the residential, commercial, industrial and transportation arenas all declined by .22, .09, 2.16 and .88 quads, respectively.
Wind power increased dramatically in 2009 to.70 quads of primary energy compared to .51 in 2008. Most of that energy is tied directly to electricity generation and thus helps decrease the use of coal for electricity production.
The significant decrease in coal used to produce electricity can be attributed to three factors: overall lower electricity demand, a fuel shift to natural gas, and an offset created by more wind power production.
Nuclear energy use remained relatively flat in 2009. No new plants were added or taken offline in this interval, and the existing fleet operated slightly less than in 2008.
Of the 94.6 quads consumed, only 39.97 ended up as energy services. Energy services, such as lighting and machinery output, are harder to estimate than fuel consumption.
The ratio of energy services to the total amount of energy used is a measure of the country’s energy efficiency. Carbon emissions data are expected to be released later this year.
The U.S. is using less energy, but more of it is coming from renewable sources, such as wind and solar.