Bay Area Rapid Transit (BART) signed deals to buy 61.7MW from NextEra Energy Resources' Sky River project, which is being repowered, and from a new 45MW solar project built by developer Recurrent Energy.
Both sites are situated in Kern County in central California, south of the Bay Area, and are due to be completed by 1 January, 2021, BART stated.
The power deals follow BART’s adoption of its Wholesale Electricity Portfolio Policy in April, in which it pledged to "support low and stable operating costs" and "maximise the use of low-carbon, zero-carbon and renewable electricity supply".
In May, BART issued a request for proposals (RFP) for renewable energy projects to contribute to its approximately 400,000MWh/year power demand for its service around the Bay Area.
Former San Francisco State Senator Mark Leno had introduced a bill in 2015 enabling BART to directly renewable energy sources. It was approved the same year.
The company said the two power deals "would not be possible" without this legislation.
BART currently gets 4% of its electricity supply from renewable sources, but with the wind and solar deals, this will increase to about 90%, the transport company stated.
As the public transport system’s energy needs increase, the proportion of its electricity needs met by the wind and solar PPAs will fall to 75% by 2025, with this share remaining constant for the remainder of the agreements’ 20-year terms, BART added.
"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," said BART District 8 director Nick Josefowitz.
Ultimately, BART plans to get 100% of its electricity from renewable sources by 2045, it added.
Transport and renewables
BART’s PPAs are not the only examples of public transport systems turning to renewable energy to meet their power needs.
Wind turbines flanking train tracks have helped power Belgian rail network operator Infrabel’s passenger trains since 2015.
Meanwhile, Metro of Santiago, the Chilean capital’s public transportation system, will "run mostly" on solar energy from a 100MW project due to be commissioned by the end of this year.