main photo
Tacoma Community College » About TCC » News & Events » Harned Center Fact Sheet » Geothermal Heating System

Geothermal Heating System


  • Number: 150
  • Locations: 100 in Parking Lot C, 50 in the central quad
  • Depth: 220 ft.
  • Projected lifespan: 100 years
  • Below-ground temperature: 56 degrees F.
  • Piping: “Poly Pipe” (Polystyrene pipe)
  • Expected length of time to completion: 4 months

System functionality

  • Water is circulated through “Poly Pipe” (Polystyrene pipe) in a closed system; groundwater is not affected.
  • Heat is exchanged between the pipes and the ground.
  • Water returns to the building at 56 degrees F.
  • The building’s heating/cooling system further modifies the water temperature to the desired degree (e.g., in winter, the water might be heated a further 12 degrees to 68 degrees).
  • Air heated or cooled by the water is used to heat or cool the building

geo thermal concept diagram

Please consider rating the content on this page:
Poor Outstanding
Your comments about the content on this page:

If you would like us to get back with you, please share your email address (optional):