The principle of operation is the same as the ASHP, the difference results from the source which is here, the ground. The heat is extracted from the ground, a fluid circulates through the buried pipes in horizontal ditches or in vertical boreholes.

ASHP GSHP Heat pump in general
  • Cheaper and quicker than GSHP (no need to install a loop in the ground)
  • COP higher than ASHP in winter (temperatures higher in the ground)
  • Cheaper to run than oil and gas boiler
  • Reduction of CO2 emissions
  • Less maintenance and safer than combustion heating system
  • Can provide cooling during summer
  • Less efficient in winter
  • Need a fan system to blow air through HX : need energy and produce noise
  • Need a defrost cycle to prevent ice on HX
  • Need more space
  • Need to do a trench in the ground
  • More expensive
  • High start-up cost
  • Heat transfer fluid can be pollutant
  • Difficult to install : understanding movement of heat, significant work in garden/house