Geothermal Energy (Cambridge (CIE) O Level Physics): Revision Note

Geothermal Energy

• Radioactive elements deep in the Earth release energy as they decay, this geothermal energy heats up the rocks, sometimes to a high temperature

• Water can be poured into shafts below the Earth's surface which is heated by the rocks and returned via another shaft as steam or hot water

• Steam can be used to turn a turbine and generate electricity, and hot water can be used to heat homes

Power Station using Geothermal Energy

Cold water is heated by the rocks and returned as hot water or steam which can be used to generate electricity

Advantages

• Renewable resource

• Reliable source of energy

• Geothermal power stations are usually small compared to nuclear or fossil fuel power stations

Disadvantages

• Few suitable locations on Earth so small scale production of electricity

• Can result in the release of greenhouse gases from underground

• Expensive to build