Geothermal Energy

Geothermal energy is harnessed from kilometres below the earth's surface through large pipes pumping water into the ground. Although probably the least known about renewable option for Australia, there are some major projects in operation especially in South Australia which is home to some of the hottest underground rocks in the country. I have found these videos which give a really good introduction to the concept, and also describe a bit about the process.

Introduction to Geothermal Energy

So how does geothermal energy work? Essentially energy is produced from the hot rocks deep below our Earth's crust. Water is sent down into shattered rock where it is heated to several hundred degrees before it returns to the surface turning steam turbines. Water is recaptured in condensers and sent back down into the ground to be reheated. This process is virtually unlimited in terms of availability and as the video below describes, hot rock resources are fairly evenly distributed around the country.

There are some ways you can design your home to take advantage of geothermal heating. If you want to find out more, then have a look at installing some Geothermal Heat Pumps.

In Australia one of the largest discovered hot spots is the cooper basin in South Australia where a 50MW facility is currently in production. With current oil prices set to sky rocket, the phasing out of coal and the necessity to hang onto our non renewable natural gas supplies, geothermal energy is one of the most exciting future energy sources. It can provide base load energy as well unlike wind and un-stored solar energy (base load solar thermal can be provided by storing excess energy in the form of heat in molten salts).

Looking further into Geothermal Energy production (in the US)

This next video is a little over dramatised, however brings up some other benefits of geothermal energy. Sulphur which can be used in fertilizer and hydrogen which can be used in fuel cells can be separated and captured from the return water or high pressure super heated steam. This video also claims that geothermal energy production is effective 95% of the time which means such plants operative more or less as a base load energy source.