Renewable energy sources are sources that will not run out. As fossil fuels decline, it is important that we research and use alternative energy sources.
The following table describes renewable sources and the energy change that takes place when they are used. Renewable source Wind energy
Method
Wind turbines turn generators to produce electricity
Energy change
Kinetic → electricity
z
Fig. 24.1.3
A wind farm uses the kinetic energy from wind to turn turbines and generate electricity
Solar energy
Solar cells generate electricity from sunlight
Light → electricity
z
Fig. 24.1.4
Solar power plants can use mirrored panels to track the Sun’s movement, maximising the amount of light converted to electricity
Hydroelectric power
A body of water is held behind a dam. When the dam is opened, the water transfers its potential energy to kinetic energy as it falls through openings in the wall of the dam. This turns turbines and generates electricity
z Fig. 24.1.5
Hoover Dam in Arizona, USA, converts the kinetic energy of the water into electricity
