Closed Loop:
Similar to the way GSHP’s work, closed loop uses a series of pipes, known as collectors which are carefully places into a pond or stream.
These pipes are then circulated with a mixture of water and anti-freeze, which absorbs heat from the body of water and then passes through the heat-exchanger into the heat pump.
The fluid is then compressed, raising the temperature so that it can be used to cater for your heating and hot water needs.
Cooled ground-loop fluid will passes back into the ground where it absorbs further thermal energy, and the process begins again.