Direct-Heat Use for Australia

Abstract

Direct geothermal heat use is an overlooked sustainable opportunity for displacing large scale electrical consumption. Recent trends for small scale (< 1MW) direct heat use by ground source heat pumps now dominate over historical space heating and bathing applications (Lund, et al., 2005). According to the 2005 review, the global total direct geothermal heat use is estimated at 28 GW. Through the addition of this new trend, direct heat has now overtaken the global geothermal electricity production of close to 10 GW (Bertani, 2005). We propose here that a new wave of utilising direct heat is imminent through the advent of newly attractive megawatt-scale applications. The biggest challenge is to drive them with low temperature (typically around 90