This helps to open up existing tiny cracks in the granite, increasing the permeability of the rock. The water is converted to steam by the heat and is channelled to the surface through another bore-hole, where it can be used to drive a turbine and thereby generate electricity. Energy from hot dry rocks is not strictly renewable because the granite mass will eventually cool down. A pilot project in the Hunter Valley is now underway. As any surfer knows, there s plenty of energy in a wave.
Waves are a form of solar energy the uneven heating of the Earth by the sun causes air to move.
This wind, in turn, transfers some of its energy to the surface layers of water bodies, particularly the ocean, thereby generating waves. Putting this energy to use has proved a titanic task for scientists. For example, sea water is highly corrosive, so making generators that are sensitive to small undulations in the sea yet strong enough to withstand the inevitable storms has been a major undertaking. But scientists are now confident that many of these difficulties are close to being solved. There is little potential for pollution either chemical, visual or noise and no greenhouse gas emissions.