Ground Source Heat Pumps

Ground source heat pumps (GSHPs) are also known as geothermal heat pumps. They are highly efficient systems for heating and cooling that tap into the Earth’s stable subsurface temperatures to regulate indoor conditions.

Here’s a concise breakdown of how GSHPs work:

The GSHP Process:

  1. Heat Exchange: GSHPs comprise two key components: the ground loop and the heat pump unit. The ground loop, often a network of pipes, is placed underground (horizontally or vertically) or submerged in a water source. It contains a heat transfer fluid, typically a mix of water and antifreeze.
  2. Heat Absorption: The heat transfer fluid circulates through the ground loop, absorbing heat from the Earth’s subsurface. Even at several feet below the surface, the ground maintains a consistent temperature throughout the year, generally warmer than winter air and cooler than summer air.
  3. Heat Pump Unit: The heat transfer fluid, now carrying the absorbed heat, is pumped to the indoor heat pump unit. This unit houses a heat exchanger and a compressor.
  4. Heat Extraction: In heating mode, the heat exchanger within the heat pump extracts heat from the fluid and transfers it to the building’s heating system, such as underfloor heating or radiators, effectively warming the indoor space.
  5. Refrigeration Cycle: The compressor in the heat pump unit elevates the temperature of the extracted heat, making it suitable for heating. The refrigeration cycle within the heat pump ensures efficient operation across different weather conditions.
  6. Distribution: The warmed air or water is distributed throughout the building, ensuring a comfortable indoor environment during the winter.
  7. Cooling Mode: During summer, GSHPs can reverse their operation to provide cooling. They extract heat from indoor air, transfer it to the heat transfer fluid, and dissipate it into the cooler Earth or a water source, offering effective cooling.


Ground source heat pumps represent an environmentally friendly and energy-efficient choice for heating and cooling buildings. By harnessing the Earth’s stable thermal energy, they deliver long-term cost savings and contribute to reduced greenhouse gas emissions, making them a sustainable solution for climate control.