Digging deep for future power  

The ABC has an article on a project to use geothermal energy to chill water for cooling - Digging deep for future power.

While geothermal power has been used since pre-Roman times for warming and bathing, the use of the technology is just starting to heat up in Western Australia.

Since 2004, Challenge Stadium in the Perth suburb of Mt Claremont has used geothermal technology to heat its swimming pools. The stadium uses a geothermal supply about 700 to 1000 metres below the ground.

Now, one Perth company plans to take the concept a whole lot further, or deeper, and use the energy for cooling.

Richard Beresford is GreenRock Energy's managing director and says the geothermal energy below the city of Perth is potentially a huge resource. "We're planning on drilling deeper than has currently been drilled in the metropolitan area to get higher temperatures, around 3,000 metres."

In the process, water is pumped below the earth's surface, and when it returns it's very hot. If the temperature is high enough, the heat energy can be transferred into electricity and the water is recycled back into the ground.

The company has teamed up with the Geothermal Centre of Excellence at the University of WA.

Mr Beresford says the temperature of the water in the UWA project will not be hot enough to produce electricity but he believes it will be sufficient to drive technology called an absorption chiller, which produces cold water.

"The absorption chiller is not new technology, but it is relatively new to think about using geothermal energy as the heat source for them. That chilled water at UWA would then be circulated into their existing system which goes around the campus feeding the various air conditioning units."