Please note that while geothermal is not a completely ‘renewable’ energy resource, we have included it here as it is one of the major emerging clean energy sources currently being developed in Victoria.
While Victoria’s geologically recent volcanic activity has resulted in an abundant underground supply of the useful ‘hot dry rock’ (or HDR) basalt, they are limited in availability due to their placement at depths considered to preclude commercial energy generation. Instead, the hydrothermal property of geothermal bores in Victoria is considered to have vast potential for geothermal direct use applications.
Geothermal temperatures in Victoria increase on average between 3 and 4ºC per 100 metres from the surface. The hot sedimentary productive aquifers (HSA) exist in what are called unconsolidated basin sediments at depths of up to 1,000 metres and have been found to provide uniform and highly productive geothermal bores. A key technological barrier will be accessing these aquifers in a way that is economically viable.
Geothermal energy is already used on a small scale across Victoria for various purposes, including at the Deep Blue Hotel Resort in Warrnambool, which uses hot mineral water from a 770 metre deep bore for all its space heating, domestic hot water, and for a pool and spa complex.
Geoscience Australia (an federal government agency) estimates that a mere 1% of Australia’s geothermal energy has the potential to supply Australia’s total annual energy requirements for 26,000 years.
The Australian and Victorian Governments have recognised the need to harness this emerging clean energy technology in the global transition toward a low carbon economy. The initiation of the Geothermal Drilling Program aims to support proof-of-concept projects and eventually establish Australia as a world leader in geothermal technology development.
Five companies have been the recipients of the Federal Government’s second-round Geothermal Drilling Program grant of $7 million each, two of which are based in Victoria.
While there are no large-scale energy projects operating at present, the combined allocation of Federal and State Government funds totaling $39 million has led to significant progress towards the establishment of geothermal test program drilling and proof-of-concept initialisation as a step towards commercial production of energy from geothermal sources.
The most significant propositions are currently located in the Geelong, Gippsland/ LaTrobe and the Otway Basin areas.
Specific projects – further information: