Source of Energy (SB. Page 44)
Teacher: Our project today is to find out about renewable energy resources. That means resources which are continually replaced and will not run out any time soon. Ramzi, what have you chosen as an example of a renewable resource?
Ramzi: The sun is a renewable source of energy. A lot of living things depend on its energy for heat and light. This energy can also be captured and used to power things. For example, if you have a solar calculator, it contains a solar cell which uses sunlight to power the calculator. Solar panels that are used on houses have thousands of solar cells, and they make electricity from the sun’s heat. The major advantage of solar energy is that, after the solar panels have been installed, electricity is not expensive to generate. Teacher: What about you, Nadia? What did you find out?
Nadia: In windy places, wind energy can be used 20 to make electricity, using wind turbines. These turbines are found in ‘wind farms’. They have blades that are attached to a generator at the centre. The wind spins the blades and the generator runs. This makes electricity. However, wind turbines can’t work if there is no wind, and sometimes the wind speed is so high it damages them.
Teacher: Ibrahim, what’s your example of a renewable resource?
Ibrahim: It’s biomass. Biomass is plant material and animal waste that is used as fuel. For example, wood is a biomass fuel as long as we continue to plant new trees to replace those we cut down. Biomass can be used to provide heat and also to make electricity. The biomass is burnt to heat water and make steam. The steam is then used to make electricity.