District of Columbia



On January 19, 2005, the Council of the District of Columbia enacted Bill A15-755, creating a renewable portfolio standard that requires 11 percent of the electricity sold in the District to come from renewable sources by 2022. The standard includes two tiers. Tier-one renewable resources include solar, wind, biomass, landfill gas, wastewater-treatment gas, geothermal, ocean (mechanical and thermal), and fuel cells fueled by tier one resources. Tier-two renewable resources include hydropower (other than pumped-storage generation) and municipal solid waste. The standard calls for an additional 0.386 percent of the state’s renewable energy to come from solar energy by 2022.




On July 24, 2007, Governor Ruth Ann Minner signed Senate Bill 19, which expanded the state’s previous renewable portfolio standard to require that 2 percent of the state’s electricity supply come from solar photovoltaics by 2019, in addition to 18 percent from other renewable sources by the same date. Sources of energy that count toward the standard include wind, ocean tidal, ocean thermal, fuel cells powered by renewable fuels, hydroelectric facilities with a maximum capacity of 30 megawatts, sustainable biomass, anaerobic digestion, and landfill gas.




On June 2, 2004, Governor Linda Lingle enacted Senate Bill 2474, which requires the state’s public utilities to provide 20 percent of their electricity from renewable sources by 2020. Sources of energy that count toward the standard include wind, solar, ocean thermal, wave, and biomass resources.


105 MW


In 1983, Iowa enacted the Iowa Alternative Energy Production law. The law requires the state’s two investor-owned utilities—MidAmerican Energy and Alliant Energy Interstate Power and Light—to contract for a combined total of 105 megawatts of their generation from renewable-energy resources, including small hydropower facilities. Sources of energy that count toward the standard include photovoltaics, landfill gas, wind, biomass, hydroelectric, municipal solid waste, and anaerobic digestion.

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