Biodiesel Use Requirement

At least 20% of all diesel fuel used to fuel state agency vehicles, vessels, and construction equipment must be biodiesel. The Washington State Department of Enterprise Services (WDES) must assist state agencies by coordinating the purchase and delivery of biodiesel if requested, using long-term contracts if necessary, to secure a sufficient and stable supply of biodiesel. For state agencies complying with the U.S. Environmental Protection Agency’s ultra-low sulfur diesel (ULSD) standard, at least 2% biodiesel (B2) must be used as an additive to ULSD for lubricity, provided that the use of a lubricity additive is appropriate and that performance and cost are comparable with other available lubricity additives. All agencies using biodiesel must submit annual consumption reports to WDES. As of 2025, Washington State ferries must use a minimum of 5% biodiesel fuel diesel-powered vessels, subject to budget funding. Additionally, the State ferries must develop a renewable diesel demonstration project and submit a report to the Legislature by September 15, 2026.

(Reference Senate Bills 5801 and 5161, 2025 and Revised Code of Washington 43.19.642 and 43.19.646)