Wave power

Wave power has experienced many designs to try and capture the huge energy resource and over the past few years a new idea has started in Scotland; a machine helps the waves to channel into a large tube to power a specially designed turbine.

How it works

At a wave power station, the waves that arrive cause the water to rise and fall in the chamber which means that air is forced in and out of a hole at the top of this chamber.

Advantages

• The energy produced from wave power is free
• It is not too expensive to operate
• Wave power can produce a great deal of energy

Disadvantages

• It all depends on the waves- all or nothing
• A suitable place is needed where the waves are consistently strong
• Some designs can be noisy
• It must be able to stand rough weather

Tidal Power

Tidal power has been around for thousands of years and is extremely predictable. The energy is taken by exploiting the rise and the fall of sea levels due to the tides. There are two types of energy systems that can be used to extract energy, these are: kinetic energy and potential energy. Kinetic energy can be taken from the moving rivers, tides and oceans and potential energy is taken from the difference in height between high and low tides.

How does it work?

Tidal power happens by generating energy from tidal currents and using turbines in a similar way to windmills. A way to capture tidal energy is to build a large dam across an estuary and store water behind it as the tide rises and then releasing the stored water through turbines at low tide.

Advantages

• Tidal power is free
• It does not produce greenhouse gases
• You do not need fuel
• It is not too expensive to maintain

Disadvantages

• A dam is very expensive to build
• Tidal power only gives power for around 10 hours a day

Geothermal energy

 The centre of the earth is around 6000 degrees centigrade, this is hot enough to melt rocks. This is where geothermal energy derives from, underground.

How does it work?

Hot rocks underground heat water to produce steam, the steam rises to the surface and this can be used to run steam turbines to produce electricity. The electricity provides hot water and heating for buildings.

Advantages

• Geothermal energy does not produce pollution
• Power stations do not take up too much room
• No fuel is needed

Disadvantages

• There are not many places to build a power station
• The type of rock is important
• Hazardous gases and mineral may rise to the surface