The performance of a geothermal installation depends on the performance of the heat pump and on the design of the ground loop.  The heating system (radiators and circulation pumps) have a large influence on the efficiency of the heat pump heating system, and should function with the lowest possible flow temperatures.

Ground source heat pumps use collectors filled with a mix of water and anti-freeze buried in the earth, either horizontally, or vertically in a borehole where land space is limited.  It consists of a system used for conveying the heat transfer medium from the warm side of the heat pump to the heat consumers.

Although more costly to install than air source heat pumps, with consistent temperatures below the surface of the earth throughout the year, ground source heat pumps deliver high levels of efficiency irrespective of seasonal variations in air temperature.

Improved thermal insulation leads to an increase in the mean surface temperatures of the space enclosing surfaces.  As a result, the same degree of comfort can be achieved at lower room temperatures.  To get the most out of any renewable energy system, it is important to ensure that the property is well insulated.