Hot Sedimentary Aquifer (HSA) Exploration and Development in Australia

Geothermal energy from Hot Sedimentary Aquifers (HSA) has significant potential in Australia. To date, the potential has been realized in multiple, small-scale (1-2.5 MW-th), direct use projects in the Perth Basin in Western Australia (WA) and in the Otway and Gippsland Basins in Victoria (VIC). These projects were limited by demand, not resource; current projects, planned at scales of 5-25 MW-th, include large-scale greenhouse projects in WA, aquaculture in VIC, and district heating in South Australia.

In contrast, commercial power generation has been more elusive. The Birdsville power plant in Queensland successfully generated 80 kW-e for ~20 years, but other attempts to realize the potential, such as the Salamander-1 (2010) and Celsius-1 (2011) exploration wells and the Winton power project in Queensland, were, or are currently, commercially unviable. These latter projects represent significant learnings for the Australian geothermal industry, analogous to ‘dry holes’ in oil and gas exploration.

Based on these learnings, certain areas can be high-graded for HSA energy exploration, appraisal, and development. Most notably, Strike Energy, holding a Geothermal Special Prospecting Area (GSPA) over much of the northern Perth Basin (NPB), has recently announced an Inferred Resource of approximately 226 MW-e (P50) in the Kingia Sandstone, which is anomalously porous and permeable at depths where the reservoir has proven temperatures greater than 150°C. If commerciality is confirmed by further appraisal, this resource could contribute to decarbonizing fertilizer (Project Haber), oil and gas, mining, and other operations in the region, as well as providing reliable, on-demand power.

This talk will review the relevant history of HSA projects in Australia and then provide an up-to-date look at new efforts to exploit HSA in Australia, including recent high-impact exploration bid rounds in multiple states.