Southern California drivers can save as much as $884 a year in fuel costs by switching to electric cars and being careful to charge them only at night, according to a new report by the Union of Concerned Scientists.

“It does take a little bit more research, a little bit more work, but that can pay off in pretty substantial savings,” said David Reichmuth, a senior engineer with UCS and the report’s author.

To help consumers decide between gas and electric cars, the Union of Concerned Scientists, a science and research-based advocacy group, chose to compare fuel costs over the course of a year in the 50 largest U.S. cities. In each city, there was at least one electricity rate plan that made driving an electric car cheaper than an average new gasoline vehicle.

Electric cars also have very low maintenance costs: they never need an oil change.

Often the biggest savings came by taking advantage of “time of use pricing,” where people charge their cars when demand for electricity is lowest, typically late at night, early in the morning and on the weekends.

Southern California Edison customers who drive electric cars can expect to save $884 a year over their gasoline car-driving counterparts, according to the report. That’s because the utility’s “time of use” rate for electric car drivers is 14 cents per kilowatt hour between 9 p.m. and 12 p.m every day. But be careful: under the “time of use” program, an EV driver can get slammed with high electricity prices during peak demand hours. During the peak winter hours, electricity costs 22 cents per kilowatt hour and 34 cents during peak summer hours.

The difference isn’t quite as stark at the Los Angeles Department of Water and Power, where EV drivers can save $571 a year compared to their gasoline counterparts, according to the report. The utility charges EV drivers who get a separate meter installed just over 12 cents per kilowatt hour between 8 p.m. and 10 a.m. and all day on the weekends, compared to 14 to 18 cents during peak demand on weekdays.

In order to take advantage of the lower “time of use” pricing, customers must request a new electric meter, said Scott Briasco, a power engineering manager at LADWP. The utility will reimburse up to $750 for the cost of the electric vehicle charger and installation of the meter, which can cost up to $2,000.

While they may be cheaper to operate, electric vehicles are still more expensive to buy new -- $4000 more than the average new gasoline car, according to the report. State and federal incentives can help shrink the gap, however Congress is considering eliminating the $7500 federal tax credit for electric vehicles (the House plan would cut the rebate, while the Senate plan would keep it intact). Either way, Californians could still qualify for a state rebate of up to $2500.

This story is part of Elemental: Covering Sustainability, a new multimedia collaboration between Cronkite News, Arizona PBS, KJZZ, KPCC, Rocky Mountain PBS and PBS SoCal.