Sound Transit's Link light rail trains will be powered with clean energy starting in 2019, the agency announced as part of an agreement with Puget Sound Energy. Sound Transit says the agreement is the first of its kind in Washington state.

The deal will last ten years as part of Sound Transit's 2015 Sustainability Plan and the voter-approved Sound Transit 3 ballot measure.

The plan aims to make Sound Transit operations entirely carbon-neutral by 2030, and also help reduce greenhouse gas emissions, future utility costs, and long-term operating expenses. Sound Transit said it also plans to stabilize 42 percent of its costs of producing electricity throughout the contract.

In order to power the trains carbon neutrally, Sound Transit says it will purchase wind energy directly from PSE's Green Direct program. The Green Direct program focuses on encouraging consumers to pursue environmentally friendly, carbon-neutral energy options, and was approved by the Washington Utilities and Transit Commission in Sept. 2016.

The agreement covers the span of light rail that is outside the Seattle city limits because that's where PSE operates. Inside Seattle, most of Seattle City Light's power comes from hydroelectric dams.