History of Enwave Seattle, Formerly Seattle Steam

Founded in 1893, Seattle Steam, now Enwave Seattle, is a privately-owned utility that provides district heat to approximately 200 buildings in Seattle's Central Business District and First Hill neighborhoods. The company produces thermal energy from five boilers located in two plants in downtown Seattle. In the fall of 2009, the company made the commitment to begin generating thermal energy primarily from a sustainable, non-fossil fuel source: biomass (also known as waste wood).

Enwave Seattle provides a cost-effective, reliable and environmentally-friendly heat source for use in heating buildings, generating hot water, humidity control and sterilization. The energy is distributed by Seattle Steam through 18 miles of pipe under approximately one-square mile of downtown Seattle to many of the city's office buildings, hospitals, hotels and college campuses.

In addition to purchasing thermal energy for heat, Enwave Seattle's customers use it for a myriad of other applications. Hospitals use high temperature steam for onsite purposes, including sterilization of medical instruments. Steam is also used for humidity control at institutions like the Seattle Art Museum, where valuable art installations have precise humidity and temperature requirements. Several of Seattle's artisan food and beverage producers, such as Beecher's Cheese and the Pike Brewing Company, use steam in their production processes.

In the fall of 2009, the company began its conversion to renewable energy by installing a new boiler that can burn clean urban waste wood, making it possible to use renewable biomass as its primary source of fuel. At full load, the biomass boiler will reduce the carbon footprint of Enwave Seattle and its customers by 50 percent, and will provide a large boost to the region's sustainability goals.

In 2014, Seattle Steam renewed its franchise agreement with the city under its new name, Enwave Seattle.

City of Seattle Department of Neighborhoods survey for Post Street Plant

Seattle Steam