On Thursday, August 2, the Sound Transit Board’s Executive Committee approved a plan to power Link almost entirely from renewable energy resources, as part of a program ST developed with regional governments and Puget Sound Energy (PSE.)

By July 2019, Sound Transit will lower its emissions by 71 percent, with renewable energy generated by a new wind farm, which will come online that month. In 2021, PSE will finish construction on a new solar array in central Washington which will allow Link to operate on 100 percent renewable energy. Systemwide, 96 percent of Sound Transit’s energy will be generated by renewables.

The contract also locks in Sound Transit’s PSE electricity rates at agreed levels for the next ten years, which could save the agency some operations cost. Sound Transit staff said that they intend to negotiate similar green energy deals with relevant utilities as the Link system expands.

The 4 percent of the energy that is not renewable will be purchased on the open energy market. Utilities use fossil fuel capacity when renewable generation is not possible or is suboptimal, or when demand exceeds renewable capacity. Solar plants can’t generate at night, for example, and wind plants can’t generate if air is stagnant.

The program is part of PSE’s Green Direct initiative, which the utility developed at the behest of regional governments and major corporate partners. According to King County Executive and ST board member Dow Constantine, the ST move is part of a larger regional push to cut carbon emissions.

“King County’s signing on to [Green Direct] reduced and is reducing our climate impact, our carbon emissions, by 20 percent,” Constantine said. “These are not really incremental steps—these are big steps forward.”

“In committing to creating electric, high capacity rail, our conversion to an all electric bus system, and our insistence that our vendor provide us with the kind of power we want, we are changing the [energy] market.”

This post has been updated to reflect the fact that Link itself will be powered entirely by renewables, while Sound Transit’s overall energy supply will be 96 percent renewable.