Here’s the need-to-know stuff about the energy source, geothermal energy!
The centre of the Earth is extremely hot – around 6000oC. Some of this heat rises up to heat rocks nearer the surface.
Where can you find geothermal energy?
Geothermal plants can be found wherever very hot rocks can be found near the surface, for example in the United States, New Zealand, Iceland and Japan. There is one small geothermal power plant in the UK, in Southampton.
How is it made into electricity?
Holes are drilled down to hot rocks – sometimes thousands of metres below the surface. Water is pumped down to the rock, where it is heated and turned to steam. This steam is then drawn up to the surface and used to propel the blades of a turbine. This is attached to a generator, which produces electricity.
What are the advantages of using geothermal energy?
- It is a renewable source of energy, which means that it will not run out.
- No fuel is needed, so once the geothermal plant is built the running costs of producing electricity are relatively low.
- Once built, geothermal plants do not produce air pollution and do not contribute to the greenhouse effect.
- The power stations do not take up much room.
What are the disadvantages of using geothermal energy?
- The right geographical location is needed, where suitable hot rocks are within drilling depth. For example, not many of these exist in the UK
- Sometimes the heat source can ‘dry up’ if too much heat energy is extracted.
- Hazardous gases and minerals can be brought up which need to be safely disposed of.