San Diego Gas & Electric announced it has filed proposals with the California Public Utilities Commission (CPUC) to install tens of thousands of electric charging stations in an effort to contribute to a state-mandated reduction of carbon emissions.

The business said the stations would encourage the use of zero-emission electric vehicles, which reduce carbon emissions. Half of all carbon emissions in San Diego come from transportation, SDG&E said.

The cost of the project was not disclosed.

The CPUC oversees SDG&E and other investor-owned electric and natural gas utilities operating in California.

Under the proposals, the utility would install up to 90,000 charging stations at single-family homes in its services area, up to 45 charging ports for ground support equipment at San Diego International Airport, electric vehicle charging stations and research meters to study the charging habits of electric trucks and forklifts at the Port of San Diego, grid-integrated charging stations at some businesses and grid-integrated charging infrastructure at four Caltrans Park & Ride locations.

SDG&E would also provide incentives to the operators of taxis, rideshare programs and shuttles to use electric vehicles and to dealerships to sell electric vehicles, were the proposals to pass, according to the company.

"SDG&E has spent more than a decade reducing our carbon footprint through the rapid expansion of clean energy," said Caroline Winn, chief operating officer of SDG&E. “We all want to breathe cleaner air, which means slowing down the impacts of climate change will require an increased focus on the areas that produce the most harmful emissions.”

The utility said the proposals were filed in response to Senate Bill 350, signed into law in 2015, which requires energy companies operating in the state to generate 50 percent of their electricity from renewable sources by the end of 2030.

SDG&E is owned by San Diego-based energy services holding company Sempra Energy.