District Energy St. Paul is a non-profit utility providing energy services to downtown Saint Paul. The core heating and cooling network serves 200 buildings in the central business district and across the river to a secondary area of commercial, light industrial, and residential development. The customer base includes higher education, hospitals, Fortune 500 companies, residential apartments, condos, and townhomes, as well as hotels, entertainment and sporting venues.
District Energy is the largest hot-water district energy system in North America and is recognized globally as a leader in integrated and dynamic energy systems. Since its transition from steam to hot water in 1983, this system has incorporated district cooling, thermal storage, solar thermal, and a biomass-fired combined heat and power plant.
Developed as a public-private partnership, District Energy has worked closely with the City of Saint Paul, Saint Paul Port Authority, local businesses leaders, and civic partners to offer competitive energy solutions and cost-based rates that have played a critical role in development for the city. District Energy has become a showcase for energy efficiency through continued efforts to evolve, to reinvent, and to integrate sustainable solutions that have earned the operations a global reputation, including recognition from the United Nations Environment Programme.
Studying, testing, and demonstrating emerging technology has been key to system achievements. Just as importantly, the people inside this operation are committed to bringing customers and community stakeholders into the story to share in their success. Whether it is multifaceted efforts to bring combined heat and power to this downtown area or to build the Saint Paul EcoDistrict sustainability education platform, District Energy is dedicated to merging partnership and innovation to advance St. Paul’s community energy model.
Ever-Green Energy’s Role: Ever-Green provides comprehensive operation and management services, energy engineering, and project management, as well as business operations, finance, legal, and outreach and education services.
- 1983 steam to hot water conversion complete and heating system start-up.
- 1993 cooling service start-up.
- 2003 District Energy became a green energy service provider following construction of an affiliated combined heat and power (CHP) plant that is fueled by a renewable resource—clean, urban wood residuals. Using renewable fuel, the CHP plant simultaneously produces about 65 megawatts of thermal energy for District Energy and 25 megawatts of electricity for the local utility. It is the largest wood-fired CHP plant serving a district energy system in the nation.
- 2011 the system was advanced further with the installation of the Midwest’s largest solar installation. It is one of the country’s largest hot water solar projects and the first in the United States to be integrated into a district heating system. The system peaks over 1.5 MW (thermal equivalent) and provides hot water and space heating to the Saint Paul RiverCentre, as well as exporting to serve other District Energy customers.
- 2013 first phase of conversion of an existing 2.5 million gallon chilled water thermal storage tank to be able to store hot water.
- 2015 commitment to end use of coal after the 2020-21 heating season. The transition from coal reduces the heating system’s CO2 emissions by 27 percent or 21,000 tons. This is the equivalent of removing 4,400 cars from the road each year.
Technologies Implemented: Hot water district heating, steam to hot water transition, district cooling, combined heat and power, waste heat recovery, thermal storage, biomass, solar thermal, snow melt