California utility regulators approved Pacific Gas & Electric's proposal to build the two largest battery systems in the world. The 4-1 vote marks a landmark development in California's quest to decarbonize its electrical system by shifting from natural gas to non-emitting sources for flexible power. "Not only will this help California integrate solar and reduce the need to ramp up polluting gas plants in the late afternoon, but it will also provide local reliability needs in an area that is currently highly reliant on gas-fired generation," said Matt Vespa, staff attorney at Earthjustice, in an email Thursday.