This report explores the policy implications of the large-scale development of geothermal energy resources and their impact on water quality and availability.
Australia could potentially produce energy from a variety of geothermal systems including:
- non-conventional engineered geothermal systems (EGS)
- hot sedimentary aquifer (HSA) developments
- shallow systems such as low enthalpy aquifers
- ground source heat pump applications.
Geothermal projects require access to water during several stages of their development and operation. Currently, some exploration and development activity is occurring in areas of low water supply and/or high water demand.
However, water resources, and in particular groundwater resources, are still to be quantified in many parts of Australia. Access rights to water for geothermal applications will therefore require careful management and discussion by both water planners and the geothermal industry.
The report is not a detailed technical report. It is predominantly intended for water planners and others with an interest in the water and energy industries, to provide a baseline of information for consideration in water management and planning decisions.
- Australia lacks conventional hydrogeothermal resources yet has excellent potential for significant energy production from deep non-conventional HSA and EGS developments.
- Geothermal legislation is subject to the provisions of water legislation in most jurisdictions. If implemented appropriately, the existing arrangements can manage geothermal project water issues.
- Where geothermal schemes recirculate working fluid in their operations, water supply and security issues are similar to those facing other sectors.
- The geothermal industry is distinctly different to the mining, oil and gas industries in terms of its potential impacts on water supply. Operations either have limited potential for the transmission of impacts towards the surface or do not involve fracture stimulation.
- Where geothermal power plants have limited access to water, this factor combined with a hot climate, will require innovative power plant cooling systems.
The report identifies a number of guiding principles that jurisdictions should consider when managing the potential impacts of geothermal-related water use:
- Geothermal companies should be treated under the same rules and regulations as other industrial water users
- Adequate allowance should be made in water sharing/allocation plans for these industrial users
- Project plans need to transparently communicate water management objectives and regulatory regimes before they are approved.
Documents for download
Geothermal energy and water use (PDF 2.4MB) (55)
Geothermal energy and water use (DOC 1.5MB) (31)