Summary of renewable energies: ENERGY AND HOW DO WE MAKE ELECTRICITY ?

« ENERGY AND HOW DO WE MAKE ELECTRICITY ? Summary What is a non- renewable source ? Most of our electricity comes from power stations that use fossil fuels like coal, oil and gas to generate the electricity. They are called non-renewable sources because you can’t make any more and they will run out. Unfortunately, burning fossil fuels produces greenhouse gases like carbon dioxide (CO2) and methane which may cause global warming. List all non- renewable source. Nuclear fuel Coal fuel fossil fuels (oil and gas or shale gas) What is a renewable source ? Renewable energy sources like the sun, wind, waves and the heat of the earth are also used to make electricity. Renewable sources can be used again and again and should not run out. List all renewable source. Solar energy Wind energy Tidal energy Geothermal energy Biomass energy Waves energy Hydro-electric energy For each one of them, complete the table below : Source How does it work ? Advantages Disadvantages Solar panels called photovoltaic cells are used to convert the sun’s energy into electricity. The Energy from the sun is free. It is relatively expensive to build solar power stations. These panels usually contain silicon and produce electricity when sunlight hits them. The sun can also be used to heat water passing through special solar collectors. The sun does not produce greenhouse gases. The sun will always be there during our lifetime. When it is cloudy or at night there is not enough light so no electricity can be made. For each one of them, complete the table below : Source How does it work ? Hydro-electricity is generated from running water. Dams are built across a lake or river in a valley to trap water. The water flows through tunnels and turns the turbines which make electricity. Advantages When electricity is generated, no greenhouse gases are made. The water used is free. It is a renewable energy source. Disadvantages The dam is expensive to build. By building a dam, the nearby area has to be flooded and this could affect nearby wildlife and plants. If it doesn’t rain much we may not have enough water to turn the turbines. For each one of them, complete the table below : Source How does it work ? Wind turbines use big blades attached to a generator. These blades catch the wind which is used to turn a generator that makes electricity. As the wind speed doubles, a wind turbine will generate eight times more energy. Advantages Disadvantages Wind is free and will not run out so the cost is in building the wind turbine. We can only use wind turbines in areas where there is a lot of wind. Wind power generation does not create greenhouse gases. Sometimes there may be days where there is little wind. There are very few safety risks with wind turbines. We need a lot of wind turbines to make a lot of electricity. Some people don’t like the way wind turbines look,.... »