United States' Energy Usage

After discussing options of renewable energy sources and the impact of oil in our economy, it was suggested to look into what the United States actually consumes energy for.  Residential, commercial, industrial, and transportation are all vital parts of our economy.  They are also markets demanding convenient and reliable energy sources.  But before claiming a new renewable energy source is the answer to less dependence on foreign oil and more environmental sustainably, the breakdown of the United States’ energy demand is necessary.

Surprisingly, the US consumed less energy in 2009 (94.6 quads) than any year since 1999 (97 quads), which was the first year of data the Lawrence Livermore National Laboratory had listed on their site.  The study used quads to measure the energy consumption, with one quad equally the energy produced from burning 36 million tons of coal.   

Even better news is the continued improvements in the renewable energy field.  In fact, according to studies by the Lawrence Livermore National Laboratory, 2009’s energy sources came from more renewable sources than in 2008.  . For example, solar energy increased in that time period from 0.09 quads to 0.11 quads.  Wind energy production also increased from 0.51 quads to 0.70 quads. Finally, the increase in geothermal energy rose from 0.35 quads to 0.37 quads in 2009.  

However, do not let the decreased energy consumption and increased renewable energy production mislead the true impacts of U.S. energy use.  The following chart is from the study conducted by the Lawrence Livermore National Laboratory and US Department of Energy reflecting the 2009 US Energy use.  The most revealing area of the chart is the total amount of energy that is wasted because of inefficiencies.  Theses inefficiencies range from light bulbs, to vehicles, to power plants’ waste heat.  This “rejected energy” counts for almost 55% of the total energy that is produced. 

Overall the United States’ energy efficiency is 42%.  Also, only 1.2% of our total energy consumption comes from solar, wind, and geothermal energy, despite the improvements in these areas.  With petroleum making up 37% of our energy sources, natural gas at 25%, and coal at 21%, the United States is still heavily dependent on exhaustible, nonrenewable sources.  

Incidentally, the largest sector that consumes energy is transportation, almost 40% of all energy consumed.   Residential, commercial, and industrial sectors are around 80% efficient, wasting on 20% of their energy.  Concurrently, the transportation sector is only 25% efficient, wasting 75% of the total energy consume.  The sobering reality is that solar panels and geothermal can help with the energy demands in the residential, commercial, and industrial sectors, but there has been limited progress in developing alternatives for fueling transportation.  

Bike paths, ethanol plants, and flex-fuel vehicles have all attempted to decrease the amount of pollution and nonrenewable energy use throughout the transportation sector.  However, more work is needed, especially in rural areas, extreme weather climates, or sprawling suburbs, where peddling over 50 miles to the nearest grocery store is not a feasible or desirable option.  The path to increased renewable energy will continue to be one of innovation and adaptation.