Seattle Steam Company

The Seattle Steam Company is a privately owned district heating public utility that provides steam (generated by burning natural gas, diesel oil, and recycled wood) to over 175 business in downtown Seattle and on First Hill via 18 miles of steam pipeline. Its plants are located on Western Avenue at Union Street, just west of the Pike Place Market, and on Post Avenue at Yesler Way, in Pioneer Square.

Seattle Steam was founded in 1893 as the Seattle Steam Heat and Power Co. It owns 18 miles of pipes under the streets of Downtown. Its average winter output is 250,000 to 300,000 lbs of steam per hour; this drops to less than 100,000 pounds in the summer.

Seattle Steam's biggest customers are Swedish Medical Center, Harborview Medical Center, and Virginia Mason Medical Center, which use the steam for heat and sterilization. Other big customers include hotels, which use the steam for heat and for generating hot water, Seattle Public Library, which uses it for heat and the Seattle Art Museum, which uses it for heat and humidity control.

• Main plant, seen here from Western Avenue

• Main plant, downtown

• Old Post Station, Seattle Steam Company (at center)

• Sign on wood handling building on Western Avenue

• Wood handling building and storage silo

• View of the main plant on Western Avenue