Tapping Into Australia's Unique Hot Energy Resources

Dr McLaren will speak about her research into Australia's heat-producing elements, and their potential for future energy production, at the Academy of Science's peak annual event Science at the Shine Dome May 7.

She says that west of the line between Cairns and the mouth of the Murray River lies a belt of rocks containing the enriched elements uranium, thorium, and potassium that are around 1.5 billion years old. These enriched elements are essentially a heat source located in the upper part of our continental crust.

'Our status as one of the most prospective countries in the world for geothermal power generation is due to this extraordinary enrichment in uranium. That's because when we bury these enriched rocks, even beneath only about two or three kilometres of sediment, they're capable of generating extremely high temperatures which we can use to generate geothermal power.'

She says that nuclear power and geothermal power use the same source of fuel – enriched uranium.

'The fundamental difference between the two energy options is the degree to which the uranium is enriched in a particular spot, and the way in which we choose to use it. So, although as geoscientists we are aware of this resource, there is still a lot of work we can do in assessing and documenting it and developing new exploration strategies and, further down the track, new technology to exploit this.

'Its an extraordinary resource that we have. Its had profound impact on our geological past, and we're at the point in time, in terms of society, of making a choice of what to do with that resource into the future.

'We have on average 2-3 times the normal concentration of uranium, thorium and potassium in the crust, so we're in a better position than probably any other country in the world to generate this type of geothermal energy.'

In terms of the future of geothermal power in Australia she says: 'Its potentially unlimited in terms of the actual resource. I think the thing that's going to constrain how and when we can use this resource for generating power is more on the engineering side, more understanding how to exploit it once we've identified how much is there.

'The exploration companies in Australia are used to exploring for base metals and gold and metallic resources. Exploring for geothermal energy is a different ask all together and we really need to develop a framework to get better data sets for us to assess different resources and better ways of looking for them.'