Marine plants and animals die and sink to the bottom of the seabed.
Coal and peat
Huge forests covered the earth
Oil and natural gas Fig. 2 How fossil fuels are formed.
Nuclear energy Nuclear energy is produced by splitting uranium atoms in a nuclear reactor to release huge amounts of heat energy. This is called nuclear fission. In a nuclear power station the heat produced is used to generate electricity.
Fig. 3 A nuclear power plant. 41.2 Renewable energy sources
Renewable energy is a sustainable energy source. It is constantly replenished by nature and can be used again and again. Examples include wind, solar, geothermal and hydroelectric energy and biofuel.
Wind energy Ireland has some of the best wind resources in Europe. There are currently 228 wind farms in Ireland. In recent years, wind farms have generated up to 20% of electricity in Ireland. On a windy day up to 50% of our electricity is generated by wind farms. Wind farms use structures called wind turbines. A wind turbine converts the motion energy of wind into electrical energy.
