Unit 1 General physics
- Tidal energy - makes use of incoming and outgoing tides
Tidal energy causes the water to move. As it does so it turns the turbines and electricity is generated. The gravitational potential energy and kinetic energy of the water converts to electrical energy.
- Geothermal energy - uses heat energy from the Earth's core
Water is fed down through pipes several kilometres underground, passing through hot rocks. These rocks heat the water until it turns into very hot steam. The steam is fed back up to ground level and is used to turn turbines and generate electricity.
- Hydroelectric energy - uses a dam to trap water
A dam is built to trap water, sometimes in a valley where there is an existing lake. Water is allowed to flow through tunnels in the dam, to turn turbines and thus drive the generators that produce electricity.