Geothermal+Power

The centre of the Earth is around 6000 degrees Celsius - easily hot enough to melt rock. Even a few kilometres down, the temperature can be over 250 degrees Celsius if the Earth's crust is thin. In general, the temperature rises one degree Celsius for every 30 - 50 metres you go down, but this does vary depending on location in volcanic areas, molten rock can be very close to the surface. Sometimes we can use that heat. Geothermal energy has been used for thousands of years in some countries for cooking and heating. Hot rocks underground heat water to produce steam. We drill holes down to the hot region, steam comes up, is purified and used to drive turbines, which drive electric generators. There may be natural "groundwater" in the hot rocks anyway, or we may need to drill more holes and pump water down to them. The first geothermal power station was built at Landrello, in Italy, and the second was at Wairekei in New Zealand. Others are in Iceland, Japan, the Philippines and the United States. In Iceland, geothermal heat is used to heat houses as well as for generating electricity. If the rocks aren't hot enough to produce steam we can sometimes still use the energy - the Civic Centre in Southampton, England, is partly heated this way as part of a district heating scheme with thousands of customers. Advantages: It does not produce any pollution and does not contribute to the greenhouse effect. The power stations so not take up much room so there is not much impact on the environment and no fuel is needed. Once you’ve built the power station the energy is almost free. Disadvantages: The big problem is that there are not many places where you can build a power station and sometimes a site might run out of steam, perhaps for decades. Hazardous gases and minerals may come up from underground and can be difficult to safely dispose of.  Back To contents
 * Geothermal Energy **