The NREL report, "The Effectiveness of State-Level Policies on Solar Market Development in Different State Contexts," includes statistical and empirical analyses to assess policy impacts in different situations. In addition, four case histories augment the quantitative analytics within each state grouping, specifically:
- Expected leaders. In Maryland, a comprehensive policy portfolio with equal emphasis on all policy types is driving recent market development.
- Rooftop rich. In North Carolina, strong interest in clean energy-related policy distinguishes it from other states.
- Motivated buyers. Delaware's experience illustrates how targeted market preparation and creation policies can effectively stimulate markets.
- Mixed. In New Mexico, the leading state for installed capacity in its peer group, policy diversity and strategic implementation have proven to be critical in effectively supporting the market.
"Although it is widely accepted that solar policies drive market development, there has not been a clear understanding of which policies work in which context," said Darlene Steward, lead author of the report. "This study provides much-needed insight into the policy scope and quality that is needed to spur solar PV markets across the United States."
The analysis shows that the effectiveness of solar policy is influenced by demographic factors such as median household income, solar resource availability, electricity prices, and community interest in renewable energy. The data also show that it's the number and the make-up of the policies that spur solar PV markets. Follow-on research expected for release this summer identifies the most effective policy development strategies for each state context and provides strategies for states to take action.
As part of a larger effort to determine the most successful policy strategies for state governments, this report builds on previous research investigating the effect of the order in which policies are implemented. The policy stacking theory, which is outlined in the "Strategic Sequencing for State Distributed PV Policies" report, aims to draw private investors to develop PV markets.
This body of work is supported by the Energy Department's SunShot Initiative, which is a national effort to make solar energy cost-competitive with traditional energy sources by the end of the decade. Through SunShot, the Energy Department supports private companies, universities, and national laboratories working to drive down the cost of solar electricity to $0.06 per kilowatt-hour.