Following its neighboring West Coast states in California and Oregon, Washington has charted its own three decade path to decarbonization, mandated by the 2019 passage of a state law, Senate Bill (SB) 5116, ordering the retirement of all coal-fired power by 2025.

Named the Clean Energy Transformation Act (CETA), SB 5116 has resulted in four rulemakings so far by the Washington Utilities and Transportation Commission (UTC), which is charged with overseeing the state’s major energy utilities transforming to 100% carbon-neutral in 2030 and l00% carbon-free by 2045.

Under CETA, the state’s electric utilities have to fully transition to “renewable, nonemitting resources” over the next 25 years, and in the meantime develop and implement plans to reduce greenhouse gas (GHG)...