In 2006, the California legislature adopted AB 32, the California Global Warming Solutions Act of 2006, which requires the reduction of statewide greenhouse gas emissions (GHG) to 1990 levels by 2020, and grants the California Air Resources Board (ARB) broad authority to regulate GHG emissions to reach this target.
The ARB developed an AB 32 Scoping Plan in 2008 that recommends specific programmatic measures to achieve these emission reductions, including a Renewable Portfolio Standard, Energy Efficiency, and Combined Heat and Power, as well as a statewide Cap-and-Trade program.
According to the Scoping Plan, the ARB will adopt regulations to acquire all cost-effective energy efficiency in the state, increase renewable power beyond the 20% level, and design a multi-sector GHG cap-and-trade program in California.
In August 2009, the CPUC issued the Alternative-Fueled in order to support California's greenhouse gas emissions reduction goals.
Cap-and-trade is a market-based mechanism intended to achieve the remaining emission reductions necessary to bring California to 1990 levels by 2020.
The CPUC is currently implementing $3.1 billion in funding for energy efficiency programs during 2010-2012 at the four largest investor owned utilities.
California's RPS is the most ambitious in the country, requiring 33% of energy procured to be from renewable sources by 2020. The standard was raised from 20% by Senate Bill X1-2 in 2011.
ARB 2013 2013 ARB Annual Report on AB 32 to the Legislature on progress of AB 32 related to addressing Climate Change.