100 likes | 269 Views
Renewable energy. Kristin Friedemann Marit Kalda. What is renewable energy? Wind power Hydro power Sun energy Tidal energy. What is renewable energy?.
E N D
Renewable energy Kristin Friedemann Marit Kalda
What is renewable energy? • Wind power • Hydro power • Sun energy • Tidal energy
What is renewable energy? • Renewable energy effectively uses natural resources such as sunlight, wind, water, tides and geothermal heat, which are naturally replenished. • Renewable energy is environmentally friendly and is not harmful to the nature. When we use renewable energy then it does not pollute as with using fossil fuels for energy.
Wind power • Wind power is the conversion of wind energy into useful form, such as electricity,using wind turbines. • The turbines have to be put in windy places such as the seaside. • The pros are: cheap, friendly to the environment, can be used effectively, there is more than enough of „fuel“and it is free. • The cons are: they disturb birds and bats, the turbines make noise, vibration and moving shadows. • In Estonia wind power is being used more and more,because we have an endless supply of wind. We have already many wind parks for example Pakri windpark.
Hydropower • Hydro power uses flowing water to generate electricity. Hydro powerstations are built on large rivers. • The pros are: environmentally friendly, effective. • The cons are: harms the fish, makes noise, costs a lot. • In Estonia we have some hydro power stations,for exampleKeila-Joa hydro powerstation, but they are small because we have only small rivers.
Sun energy • Solar energy is energy from the Sun in the form of heat and light. • There are three main ways that we use the Sun's energy : 1) Solar Cells 2)Solar water heating 3)Solar Furnaces • Solar energy is free - it needs no fuel and produces no waste or pollution. • In sunny countries, solar power can be used where there is no easy way to get electricity to a remote place. • Doesn't work at night. • Very expensive to build solar power stations. Solar cells cost a great deal compared to the amount of electricity they'll produce in their lifetime. . .
Tidal power • Energy from the sea - The tide moves a huge amount of water twice each day . • converting it into useful electrical power is not easy • It produces no greenhouse gases or other waste. • It needs no fuel. • Only provides power for around 10 hours each day, when the tide is actually moving in or out. • Only works when tide is going in or out • around 20 sites in the world have been identified as possible tidal power stations.