NREL Report Relates State Policies to Renewable Energy Development

December 02, 2009

DOE's National Renewable Energy Laboratory (NREL) recently issued a report showing that clean energy development is spreading rapidly throughout the country, often following public policies designed to spur renewable energy growth. According to the report, "State of the States 2009: Renewable Energy Development and the Role of Policy," California led the nation in terms of total non-hydroelectric renewable generation in 2007, while Maine generated the largest percentage of electricity from renewable resources other than hydropower, at 26.1%. Twenty-nine states and the District of Columbia have adopted a renewable portfolio standard (RPS), a policy that requires utilities to draw a percentage of their power from renewable energy sources. All but a dozen states have implemented policies for connecting renewable energy systems to the power grid, known as interconnection, while all but eight allow customers to earn credit for power fed back into the grid, a policy called net metering.

The NREL report also went beyond simply tabulating data by examining the impact of renewable energy policies using statistical and empirical methods. That analysis found that states that had a net-metering policy in place in 2005 had more generation from non-hydropower renewable energy sources in 2007 than states that did not. States that required utilities to tell their customers the energy sources used to produce their electricity and that also required utilities to offer "green power"—electricity produced from renewable energy sources—ended up with more renewable energy development. The report also found several features of RPS policies that significantly contributed to increased renewable energy development, but it failed to find a perfect combination of features for an RPS policy that correlated with significant increases in renewable energy. See the report (PDF 4.2 MB). Download Adobe Reader.