Solar Energy and the Williamson Act: Legal Developments and Recent Trends

by Bradley Brownlow^*

Less than a decade after enactment of the California Global Warming Solutions Act of 2006 (AB 32), California stands as a global leader in the shared endeavor to reduce greenhouse gas emissions to sustainable levels. The electricity sector, however, remains one of California’s largest greenhouse gas contributors, historically responsible for approximately 23 percent of statewide emissions.¹ To reduce these emissions, the Legislature implemented renewable portfolio standards (RPS) that require the state’s investor-owned utilities (IOUs) to procure 33 percent of their annual retail electricity sales from eligible renewable resources by 2020.²

Adoption of the RPS requirements prompted a wave of renewable energy development in the state. Between 2008 and 2015, roughly 8,000 megawatts (MW) of renewable energy capacity achieved commercial operation, with 2,541 MW of additional capacity projected to come online in 2015.³ As a result, California’s IOUs now serve approximately 21 percent of retail sales with RPS-eligible generation and are well on their way to achieving the 2020 RPS mandate.⁴

One side effect of California’s RPS success is the recent slowdown of utility-scale (i.e., >20 MW) solar electric generation development.⁵ As the installed capacity of clean energy resources nears the 2020 RPS target, IOUs are executing fewer of the power purchase agreements that help fuel utility-scale solar development.⁶ However, the solar industry is hopeful that this trend will reverse following Governor Jerry Brown’s January 2015 inaugural address, in which he called for expanding California’s renewable energy target from thirty percent by 2020 to fifty percent by 2050.⁷ If the RPS is raised to achieve the Governor’s long-term clean energy vision, a new wave of utility-scale solar development may follow. Indeed, achieving California’s long-term greenhouse gas reduction goals may depend on it.⁸