Geothermal energy

Geothermal energy refers to energy (heat) that is generated within the earth. Geothermal energy is considered to be a baseload renewable energy source that can operate around the clock and has low emissions. It is already being harnessed in many places around the world. The Geological Survey of Western Australia (GSWA) has been mapping the sedimentary basins of Western Australia in the search for viable energy sources.

In Western Australia, geothermal resources include shallow direct use resources which target sedimentary aquifers; deeper natural reservoirs (sedimentary or fractured reservoirs) for direct use applications as well as electricity generation; and Enhanced Geothermal Systems, which require the enhancement or creation of permeability, and may be used for both direct use applications and electricity generation.  

Current drilling technology limits economic development of geothermal resources to a maximum depth of about 5 km. The temperature at this depth varies across the Australian continent due to a range of geological factors, such as high heat-generating basement rocks. The heat is derived from the decay of radiogenic elements in the rocks (particularly granite) and is trapped by layers of sediment that act as insulating blankets. Western Australia has significant potential for geothermal energy generation due to its abundance of radiogenic basement rocks, coupled with sedimentary cover. 

Significant geothermal resources in Western Australia have been identified in the Canning, Carnarvon and Perth Basins, where the depth to 200 °C is less than 5 km (see image). Direct-use geothermal is being used successfully in Western Australia for the heating of swimming pools. Electricity generated from geothermal has the potential to play an important role in Australia's energy transition. GSWA has conducted several studies to assess the potential for geothermal energy resources and development within the Canning, Carnarvon, Perth and Officer Basins. To view GSWA publications search eBookshop.

Geothermal energy exploration in Western Australia was legislated in 2008. Since then several companies have been exploring for geothermal energy, mostly in the Perth Basin. 

Contact
For further information contact:
basinenergy.geoscience@dmirs.wa.gov.au