Direct Energy

Geothermal Heating and Cooling Solutions

Geothermal energy is renewable and available 24 hours a day, 365 days a year.  It comes from two replenishing sources: the Earth�s core in the case of hot-rock, several-kilometer-deep power generation, and solar energy in the case of Geothermal Heat Pumps (GHPs, also referred to as Ground Source Heat Pumps or GeoExchange).  About 50% of incoming solar energy is absorbed - GHPs harvest solar energy from the shallow Earth via ground loops circulating a fluid.

Direct Energy supplies and installs Direct Exchange GHPs (also referred to as Direct GeoExchange) throughout Australia.  Direct GHPs have greater efficiency than water-loop GHPs because they:
(i)	use thermally conductive copper instead of insulating plastic;
(ii)	circulate refrigerant directly underground allowing latent heat transfer on evaporation or condensation; and
(iii)	 do not require an intermediate water-to-refrigerant heat exchanger between the ground loops and compressor.
Direct GHPs transfer heat via 30-metre deep, 75-mm wide bore holes compared with 100-metre deep, 150-mm wide bores used for water-loop GHPs.  A continuous, closed loop of copper piping is inserted and sealed with a thermally conductive grout (cement).  At 30-metres the Earth remains at a stable temperature all-year-round, ranging from 12 ââ?¬â?? 18oC throughout Australia.  The smaller temperature difference between the heat source/sink and the building to be heated/cooled means less energy is required by the compressor compared to conventional heating and cooling systems, resulting in up to 75% energy savings.  Further savings follow from geothermal water heating which is a free by-product of the refrigerantââ?¬â?¢s superheat in summer.

As well as very effectively abating greenhouse gases, GHPs can efficiently heat commercial quantities of water to assist in water conservation via stormwater reclaim and desalination plants.
Direct Energy�s GHPs are manufactured at a facility which uses this technology and state-of-the-art energy-efficie