Thermal energy consumption in Ireland is 1.032 Mtoe (155.67 TWh) for domestic heating. For the tertiary sector it is 0.421 Mtoe (63.50 TWh) (Dubuisson, 2002). Less than 1% of Irish households are heated using a heat pump. This contrasts sharply with Switzerland, one of the world leaders in heat pump technology, in which 67% of homes are equipped with a heat pump (Rybach and Sanner, 2000). The reasons for such a low number of installations in Ireland is due to a) low public awareness of heat pump technology and its advantages over conventional heating systems, b) air conditioning, which drove the heat pump market, especially in the US, is not required in Ireland, c) a lack of hot springs, a feature which usually promotes the use of ground source heat pumps (GSHP) and d) few installers to promote and install heat pump systems