There are many different types of renewable energy resources. Renewable sources of energy are constantly being replaced and will never run out. The most important in Scotland are: wind power, wave power, hydroelectric power, solar power and in the future, tidal power.
Wind turbines have huge blades mounted on a tall tower. The blades are connected to a generator. As the wind blows, it transfers some of its kinetic energy to the blades, which turn and drive the generator. Several wind turbines may be grouped together in windy locations to form wind farms.
Waves in the sea make the water rise and fall. Wave power generators use the kinetic energy in the waves to drive electricity generators inside them.They are buoys that are strung together in long lines so that large amounts of electricity can be generated at the same time.
Many inlets in the Highlands and Islands of Scotland contain these long strings of buoys to help boost local power levels.
Hydroelectric power stations use the energy inside moving water to convert to electrical energy. The water comes from behind a dam built across a river valley. The water high up behind the dam contains gravitational potential energy. This is transferred to kinetic energy as the water rushes down through tubes inside the dam. The moving water drives electrical generators, which may be built inside the dam.
We use the sun as a source of energy in two main ways: solar cells and solar panels. However, only solar cells generate electricity.
Solar cells are devices that convert light energy directly into electrical energy. You may have seen small solar cells in calculators. Larger arrays of solar cells are used to power road signs in remote areas, and even larger arrays are used to power satellites in orbit around Earth.
The movement of the tides flowing in and out can be harnessed using a generator like the one shown in the diagram.
Two large turbines are connected to a generator, which converts the movement of the tides into electrical energy. The turbines look very similar to wind turbines but are specially designed to work under water.
These turbines may one day be seen in many sea lochs around Scotland.