In this section, you will learn: zzabout the different types of renewable energy resources.
Hydroelectric Turbine Wind farm Solar cell
Solar panel Geothermal Biomass Biofuel
The energy resources we rely on now are mostly non-renewable or finite, meaning that they will eventually run out. They also cost a lot of money. We need to develop our production and use of renewable energy. There are many different types of renewable energy sources.
• Hydroelectric power (HEP) • Wind energy • Solar energy
Hydroelectric power (HEP)
Hydroelectric power is the creation of electricity by using the force of falling water.
A dam is built across a river to trap the water. (A dam is a concrete wall that controls the flow of the water.) When part of the dam is opened water rushes through. The water is used to turn a turbine, which generates electricity.
Turbine:
a machine where liquid (water) or gas (wind) flows through and turns a wheel with blades in order to produce power.
: Figure 5.16 A hydroelectric power station
HEP is the largest source of renewable energy. In 2015 it generated over 16 per cent of the world’s electricity.
Examples of HEP stations are Inniscarra dam in Co. Cork, Ardnacrusha dam in Co. Clare and the Three Gorges dam in China.
HEP stations need the following:
1. Water supply: HEP stations need a constant supply of water. They are built on fast-flowing, high- volume rivers.
2. Slope: A HEP station needs to be built where there is a drop in the course of the river. This drop causes the water to flow quickly.
3. Bedrock: The reservoir behind the dam of a HEP station must be built on impermeable bedrock. This is so the water in the reservoir does not seep away and remains as a constant water supply.
4. Climate: HEP stations need to be situated in areas with high levels of rainfall. Go to the Case Study on page 80 of this chapter to learn more about hydroelectric power .
• Geothermal energy • Biomass
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Energy and the Environment: How fuelling our needs impacts on the world we live in
