District Cooling

District Cooling St. Paul provides year-round chilled water services to over 100 buildings in Saint Paul, totaling over 19 million square feet. The chilled water service replaces stand-alone chillers and cooling towers by providing reliable cooling served at 42°F.  District cooling significantly reduces the use of ozone-depleting refrigerants, lowers potable water usage at the building, and uses energy more efficiently.  District Cooling St. Paul utilizes electric centrifugal and low-pressure steam absorption chillers. The district cooling service has proven to be just as reliable as district heating service, exceeding 99.99% since service began.

By replacing stand-alone chillers and cooling towers and providing buildings, buildings are connected to the underground system of pipes that provides reliable chilled water between 38°F and 42°F (on average). The piping system is connected to chiller plants and thermal storage facilities. This allows one off-site chiller or production asset to replace multiple chillers in multiple buildings, allowing higher efficiency for production and for customers. These cooling systems are flexible when managing load and during extreme weather events.

How it Works

District cooling is the process of distributing chilled water from a central generation source for cooling and air-conditioning. This chilled water can be produced from different sources, including electric chillers, absorption chillers, combined heat and power, industrial waste energy, or cold sea or lake water.

Benefits

  • 99.99% reliability of service
  • Decreases use and emission of refrigerants
  • Off-peak cooling stabilizes energy costs for district cooling customers
  • Improves energy security and community resiliency
  • Reduces air emissions by centralizing cooling and reducing the need for chillers and small, inefficient air conditioning units