BAY AREA — BART's board of directors voted Thursday to purchase renewable energy from two new wind and solar projects near Bakersfield in a pair of 20-year contracts that are expected to save an estimated $173.9 million over two decades.

NextEra Energy's Sky River wind project and Recurrent Energy's Gaskell West 2 solar project, both in Kern County, are expected to put out 257,000 megawatt hours and 130,000 megawatt hours per year respectively when they come online. BART currently uses roughly 400,000 megawatt hours of electricity per year, and together these two projects will provide roughly 387,000 megawatt hours. "BART receieved a robust set of competitive bids in response to the Request for Proposals that was issued in May 2017," BART Sustainability Director Holly Gordon said in a statement.

"The price per kilowatt hour that BART will pay when the projects begin operating is lower than what BART currently pays for energy," Gordon said. "That low price will be locked in for 20 years, resulting in significant cost savings ... over the long run." BART currently uses renewable energy for roughly 4 percent of its power supply, but these projects will account for roughly 90 percent of the district's electricity in 2021, according to projections.

BART officials anticipate that the districts energy needs will rise, however, and as that happens Sky River and Gaskell West 2 are expected to provide roughly 75 percent of the electrical supply around 2025. This exceeds the requirements of BART's Wholesale Electricity Portfolio Policy, which requires the district to source at least 50 percent of it's electricity from renewable sources by 2025.

"These agreements demonstrate BART's commitment to being a climate-forward transportation agency and establish the agency as a national leader when it comes to utilizing renewable energy," Nick Josefowitz, BART

District 8 director, said in a statement.