In the recent attempts to stimulate alternative energy sources for heating and cooling of buildings, emphasise
has been put on utilisation of the ambient energy from Ground Source Heat Pump Systems (GSHPs) and other
renewable energy sources. Exploitation of renewable energy sources and particularly ground heat in buildings can
significantly contribute towards reducing dependency on fossil fuels. Geothermal Heat Pumps (GSHPs), or Direct
Expansion (DX) ground source heat pumps, are a highly efficient renewable energy technology, which uses the earth,
groundwater or surface water as a heat source when operating in heating mode or as a heat sink when operating
in a cooling mode.
It is receiving increasing interest because of its potential to reduce primary energy consumption
and thus reduce emissions of the Greenhouse Gases (GHGs). The main concept of this technology is that it utilises
the lower temperature of the ground (approximately <32°C), which remains relatively stable throughout the year,
to provide space heating, cooling and domestic hot water inside the building area.
Recent attempts to stimulate alternative energy sources for heating and
cooling of buildings has emphasised the utilisation of the ambient energy from ground source and other renewable
energy sources. The purpose of this study, however, is to examine the means of reduction of energy consumption
in buildings, identify GSHPs as an environmental friendly technology able to provide efficient utilisation of energy
in the buildings sector, promote using GSHPs applications as an optimum means of heating and cooling, and to
present typical applications and recent advances of the DX GSHPs.
It also focuses on the optimisation and improvement of the operation conditions of the heat cycle and performance of the DX GSHP. It is concluded that the direct expansion of the GSHP, combined with the ground heat exchanger in foundation piles and the seasonal
thermal energy storage from solar thermal collectors, is extendable to more comprehensive applications.