According to the latest issue of the U.S. Energy Information Administration's (EIA) "Electric Power Monthly," with preliminary data through to December 31, 2012, non-hydro renewable sources (i.e., biomass, geothermal, solar, wind) increased by 12.8 percent last year compared to 2011 and provided 5.4 percent of net U.S. electrical generation.

Solar increased by 138.9 percent while wind grew 16.6 percent, geothermal by 9.6 percent, and biomass (i.e., wood, wood-derived fuels, and other biomass) by 1.6 percent. Moreover, since 2007, non-hydro renewables have more than doubled their contribution to the nation's electrical supply, according to the report.

At the same time (2012 compared to 2011), total net U.S. electrical generation dropped by 1.1 percent with petroleum coke and liquids down by 24.1 percent, coal by 12.5 percent, and nuclear by 2.6 percent. In fact, coal, which only a decade ago provided more than half the nation's electricity, fell to 37.4 percen percent of net electrical generation while nuclear, for the first time in many years, slipped below 19.0 percent. Conventional hydropower also declined by 13.4 percent due to last year's drought and lower water flows, but natural gas expanded by 21.4 percent to provide 30.3 percent of net electrical generation.

Conventional hydropower and non-hydro renewable sources combined accounted for 12.22 percent of net U.S. electrical generation: hydropower - 6.82 percent, wind - 3.46 percent, biomass - 1.42 percent, geothermal - 0.41 percent, and solar - 0.11 percent. However, as EIA has noted in the past, these figures do not comprehensively reflect distributed, non-grid connected generation and thereby understate the full contribution of renewables to the nation's electrical supply. These additions understate actual solar capacity gains. Unlike other energy sources, significant levels of solar capacity exist in smaller, non-utility-scale applications - e.g., rooftop solar photovoltaics.

EIA's report also reveals the top renewable-electricity generating states for 2012: 

  • Top Five Hydropower States: Washington, Oregon, California, New York, Idaho
  • Top Five Non-Hydro Renewables States: Texas, California, Iowa, Minnesota, Oklahoma
  • Top Five Wind States: Texas, Iowa, California, Oklahoma, Illinois
  • Top Five Biomass States: California, Florida, Maine, Georgia, Alabama
  • Top Five Geothermal States: California, Nevada, Utah, Hawaii, Idaho
  • Top Five Solar States: California, Arizona, Nevada, New Jersey, New Mexico 

Technical advances, falling costs, and the desire to address climate change have combined to rapidly expand the contribution of renewable energy to the nation's electrical generation. With the right policy incentives, one can foresee these cleaner energy sources providing the bulk of the nation's electrical needs within a generation.

Lead image: Growing graph via Shutterstock