California governor signs clean energy bill

California raised its climate ambitions today as governor Jerry Brown (D) signed a bill that will require the state to use zero-carbon resources for all its electricity by 2045.

Brown also went a step further by issuing an executive order calling for the state to achieve carbon neutrality by that same year.

"This bill and the executive order put California on a path to meet the goals of Paris and beyond," Brown said. "It will not be easy. It will not be immediate. But it must be done."

State lawmakers passed the bill, SB 100, in the closing days of this year's legislative session, despite opposition from California's investor-owned utilities. It allows electricity providers to tap nuclear plants, natural gas generators that capture and store their carbon, hydro and other clean energy sources to achieve the target, but the state will likely rely heavily on solar and wind farms that are paired with batteries.

The new law also raises the state's renewable portfolio mandate to 60pc of electricity use by 2030, up from 50pc. The state's major utilities were on track to meet the previous goal a decade early.

Environmental groups said the move sends a strong signal to other countries and US states to shift away from fossil fuels.

"It is impossible to overstate how significant it is for a state as large and influential as California to commit to 100pc clean energy," Sierra Club executive director Michael Brune said.

Brown signed the bill days before the start of the Global Climate Action Summit he will co-host in San Francisco. The event seeks to re-energize cities, companies and investors to commit to the goals of the Paris agreement, which seeks to limit global temperature increases to no more than 2° Celsius.

The executive order sets a statewide goal for California to remove just as much carbon from the atmosphere at it emits by 2045 and maintain "net negative" emissions thereafter.

Brown said California would reach carbon neutrality through "continued significant reductions" of greenhouse gas (GHG) emissions and increased carbon sequestration in forests, soils and other landscapes.

The state aims to cut GHG emissions by 40pc from 1990 levels by 2030 and 80pc by 2050.

With the executive order, California joins 20 countries and at least 40 cities, states and provinces planning to go carbon neutral by mid-century or sooner, according to Brown's office. Hawaii has set mandates to use 100pc renewables and become carbon neutral by 2045.