WA SB6121

Defines "large energy use facility" as any facility using or capable of using 20 megawatts or more of electricity, including data centers

Requires the Utilities and Transportation Commission (for investor-owned utilities) and Department of Commerce (for consumer-owned utilities) to develop model tariffs for large energy use facilities by June 30, 2027

Beginning January 1, 2028, mandates electric utilities to enter into contracts of 10 years or longer with large energy use facilities, requiring these customers to pay minimum amounts based on projected usage

Tariffs and contracts must allocate costs proportionally to large energy users and protect residential, small commercial, and existing industrial ratepayers from rate increases caused by infrastructure investments for these facilities

Requires the Department of Commerce to submit biennial reports to the legislature on load trends and implications from large energy use facilities, with the reporting requirement expiring January 2, 2036