Energy Consumption in the U.S. by Source & Sector
Lawrence Livermore National Laboratory recently released an energy consumption chart categorized by source and sector. Copied below, the chart details the quantities of energy of the various primary fuels and the derived usable energy delivered to the residential, commercial, industrial, and transportation sectors. The chart also specifies the amount of energy that the generation of electricity consumed and where the electricity was ultimately used. In total, the U.S. consumed 95.1 Quads of energy (1 Quad = 1,000,000,000 MMBtu) in 2012, down 2.2 Quads from 2011. Biomass made up 5% of the primary fuels consumed, while fossil fuel made up 82%. The use of renewables in the U.S.’s energy portfolio has grown in recent years, increasing from 7.3% of the total primary fuels in 2008 to 9.3% in 2012. Surprisingly though, the energy infrastructure in the U.S. became considerable more inefficient in the amount of useful energy that was derived from the primary fuels. From 2008 to 2011, between 42.3% and 42.9% of the bound energy in the primary fuels was converted into usable energy services. The rest of the bound energy that was not used in an ‘energy service’ was lost to heat (out of a tail pipe or smokestack, for example) or via other routes of loss. In 2012, however, the efficiency of the energy infrastructure converted 38.9% of the energy in the fuel to useful energy, representing a decrease of roughly 3.5%. Intrinsic losses during the production of usable energy are unavoidable, particularly with combustion. There are, however, various technological advancements that allow a variety of proven strategies to improve the overall efficiency that usable energy is produced, for example: CHP plants, hybrid auto-mobiles, super-critical boiler, etc.. The decrease seen in 2012 is hopefully an anomaly, and increases in the overall efficiency will be observed as older, inefficient power plants, automobiles, space heating systems are retired. Biomass and other renewables have a large part play in a more sustainable energy infrastructure. Yet, beyond renewables, gains in the efficiency of how energy is currently produced need to be exhaustively pursued if climate mitigation goals have any chance of being reached.