Level: JHS, Basic 7 | Subject: Integrated Science | Strand: Forces and Energy | Topic: Electricity Generation and Its Effects on the Environment
Curriculum reference: B7.4.2.1 (NaCCA Integrated Science).
1. How Electricity is Generated
- Most electricity is made by a generator. A turbine spins a magnet near coils of wire, and this produces an electric current.
- Something must turn the turbine: falling water, steam, wind or an engine.
2. Sources of Electricity
| Source | How it works | Ghana example |
|---|---|---|
| Hydroelectric | Falling water turns the turbine | Akosombo and Bui dams |
| Thermal | Burning fuel (gas, oil, coal) makes steam that turns the turbine | Takoradi and Aboadze plants |
| Solar | Solar panels change sunlight directly into electricity | Solar farms and solar home lights |
| Wind | Moving air turns the blades | Wind farms along the coast |
| Nuclear | Heat from splitting atoms makes steam | Not yet used in Ghana |
| Biomass | Burning waste from plants or animals | Waste-to-energy projects |
3. Renewable and Non-renewable Sources
- Renewable sources do not run out: water, sun, wind.
- Non-renewable sources can finish: coal, oil, natural gas.
4. Effects on the Environment
- Thermal plants: release smoke and carbon dioxide. This pollutes the air and adds to global warming and acid rain.
- Hydroelectric dams: flood large land areas, destroy forests and farms, move villages and change river life. They depend on rainfall, so a dry season lowers the power.
- Solar and wind: clean, but need large land and cost a lot to set up.
- Nuclear: gives a lot of power but produces dangerous radioactive waste.
5. Saving Electricity
- Switch off lights and appliances not in use.
- Use energy-saving bulbs (LED).
- Use more solar power.
- Avoid damaging power lines and report faults.
Remember: Electricity is made when a turbine turns a generator. Renewable sources are cleaner, while burning fuel pollutes the air.
Ready to practise?
Education Always (education.inspiringalways.com). Original notes written to follow the NaCCA Basic 7 Integrated Science curriculum.