Renewable energy resources are resources which do not run out. Using renewable energy resources to generate electricity is an alternative to using fossil fuels. They also tend to be less harmful to the environment compared to non-renewable energy resources.
Below are examples of renewable resources:
Let’s look at a few in more detail:
Wind is air that is in motion, so the kinetic energy of wind is the renewable energy.
How wind energy works:
1. When the wind blows, it transfers some of its kinetic energy to the blades
2. This directly drives the turbine
3. The turbine turns the generator, which generates the electricity
Solar energy is energy from the sun, which can be converted to electricity by using solar panels. As long as there is sunlight, we can use solar energy.
Solar panels are made out of photovoltaic cells and they absorb energy from the sun. This is the one renewable energy source that does not involve a turbine when generating electricity. The solar panels are directed where they can get the most sunlight throughout the day.
How solar energy works:
1. Solar panels absorb sunlight
2. The absorbed sunlight is used to generate electricity
In the word biofuel, it includes ‘bio‘ which relates to living things (plants in this case) and ‘fuel‘ which is a material you burn to produce heat or power.
Biofuels are produced from plant materials.
When plants burn, they release carbon dioxide (CO2). However, this is not as harmful as burning fossil fuels because when plants grow. they take in CO2 through photosynthesis. This means when you burn the plants, you’re just releasing the absorbed CO2 and not releasing any extra CO2. Therefore, this means biofuels are carbon neutral.
Biofuels are better for the atmosphere than burning fossil fuels that have carbon locked inside of them. When fossil fuels burn, they release new CO2.
In the word geothermal, it includes the word ‘geo‘, which relates to the ground/land part of the earth and ‘thermal‘ which relates to heat.
How geothermal energy works:
1. Water is pumped underground
2. The water pumped down is heated by hot rocks underground
3. This water then turns to steam (water vapour)
4. Steam is used to turn the turbine
Geothermal energy is a great alternative to burning fossil fuels because it does not involve burning fuels, which means that no CO2 is being released and there are no fuel costs. The hot water and steam can even be used to heat buildings.