SUGAR LAND--January 21, 2013--Written by Richard Finlayson, Senior International Editor for Industrial Info Resources (Sugar Land, Texas)--Wind, solar power , geothermal energy, hydro and biomass were the renewable energy sources that together accounted for 49.1% and 12,956 megawatts (MW) of all U.S. electrical generating capacity installed in 2012, according to the latest Energy Infrastructure Update by the Federal Energy Regulatory Commission. December alone saw more than 25% of the new capacity entering operation with 3,276 MW.