CIE IGCSE Geography – Energy
1. Key Definition: Energy
Energy is the ability to do work and power machines, transport, homes and industries.
Energy is essential for:
- Industry (manufacturing, mining, factories)
- Transport (cars, planes, ships)
- Electricity generation
- Heating and cooking
- Agriculture (machinery, irrigation)
Importance of Energy for Development
Energy availability strongly affects a country's level of development.
| High-income countries | Low-income countries |
|---|---|
| High energy consumption | Lower energy consumption |
| Advanced industries | Mostly agriculture |
| Use electricity and modern fuels | Depend more on fuelwood and charcoal |
Example:
- The United States uses huge amounts of electricity per person.
- Rural areas in Ethiopia still rely heavily on fuelwood.
2. Types of Energy
Energy sources are divided into two main categories:
Non-renewable energy
- Limited supply
- Will eventually run out
- Formed over millions of years
Renewable energy
- Naturally replenished
- Sustainable if managed properly
3. Non-Renewable Fossil Fuels
Definition
Fossil fuels are fuels formed from the remains of plants and animals buried millions of years ago.
Main fossil fuels:
- Coal
- Oil (petroleum)
- Natural gas
3.1 Coal
Formation
Coal formed from ancient forests buried under sediments, compressed by heat and pressure.
Uses
- Electricity generation
- Steel production
- Industrial fuel
Example major producers:
- China
- India
- United States
Advantages
- Large reserves available
- Relatively cheap
- Reliable energy supply
Disadvantages
- Major source of air pollution
- Produces carbon dioxide (CO₂) causing climate change
- Mining causes land degradation
3.2 Oil (Petroleum)
Formation
Oil formed from marine organisms buried under seabed sediments.
Uses
- Fuel for cars and airplanes
- Plastics and chemicals
- Electricity generation
Major oil producers include:
- Saudi Arabia
- United States
- Russia
Advantages
- Very energy efficient
- Easy to transport
- Essential for transport systems
Disadvantages
- Oil spills damage marine ecosystems
- Non-renewable
- Causes greenhouse gas emissions
3.3 Natural Gas
Uses
- Cooking
- Heating homes
- Electricity generation
Example countries using large amounts:
- Russia
- United States
- Qatar
Advantages
- Cleaner than coal and oil
- Efficient energy source
Disadvantages
- Still produces greenhouse gases
- Extraction can damage environments
4. Renewable Energy Sources
Renewable energy comes from natural sources that do not run out.
Main types required by the syllabus:
- Hydroelectric power (HEP)
- Wind
- Solar
- Geothermal
- Wave and tidal
- Biofuels
4.1 Hydroelectric Power (HEP)
Definition
Electricity generated from flowing water.
Water stored behind a dam flows through turbines to produce electricity.
Example:
- Three Gorges Dam
- Aswan High Dam
Advantages
- Renewable
- Low pollution
- Reliable electricity supply
Disadvantages
- Expensive to build
- Flooding of land
- Displacement of people
- Ecosystem disruption
4.2 Wind Power
Electricity generated by wind turbines.
Example countries:
- Denmark
- Germany
- United Kingdom
Advantages
- Renewable
- No greenhouse gases
- Low operating costs
Disadvantages
- Wind is not constant
- Visual pollution
- Noise from turbines
4.3 Solar Power
Uses sunlight to generate electricity using solar panels.
Example:
- Morocco has large solar power plants in desert areas.
Advantages
- Renewable
- Abundant in sunny regions
- Low pollution
Disadvantages
- Expensive initial installation
- Works only during daylight
- Less effective in cloudy regions
4.4 Geothermal Energy
Energy produced from heat inside the Earth.
Example:
- Iceland uses geothermal energy widely.
- Kenya produces geothermal electricity in the Rift Valley.
Advantages
- Reliable
- Renewable
- Low emissions
Disadvantages
- Only available in volcanic regions
- High initial cost
4.5 Wave and Tidal Energy
Wave power
Energy from ocean waves.
Tidal power
Energy from rising and falling tides.
Example:
- La Rance Tidal Power Station
Advantages
- Renewable
- Predictable energy
Disadvantages
- Expensive technology
- Limited suitable coastal locations
4.6 Biofuels
Fuel produced from plants or organic materials.
Examples:
- Ethanol
- Biodiesel
Major producers:
- Brazil
- United States
Advantages
- Renewable
- Reduces dependence on fossil fuels
Disadvantages
- Uses farmland that could grow food
- May cause deforestation
5. Fuelwood
Definition
Wood used as a fuel for cooking and heating.
Common in many low-income rural areas.
Example:
- Rural communities in Uganda and Nepal rely heavily on fuelwood.
Advantages
- Cheap and accessible
- Renewable if forests are managed
Disadvantages
- Deforestation
- Indoor air pollution
- Health problems
6. Nuclear Power
Definition
Electricity generated by splitting uranium atoms (nuclear fission) in a nuclear reactor.
Example countries:
- France (large nuclear energy producer)
- Japan
- United States
Example nuclear accident:
- Chernobyl Disaster in Ukraine.
Advantages of Nuclear Power
- Produces large amounts of electricity
- Low greenhouse gas emissions
- Reliable continuous power supply
- Reduces reliance on fossil fuels
Disadvantages of Nuclear Power
- Risk of radioactive accidents
- Radioactive waste disposal problems
- Very expensive to build
- Security concerns
7. Comparing Energy Sources
| Energy type | Renewable? | Pollution | Reliability |
|---|---|---|---|
| Coal | No | High | Reliable |
| Oil | No | High | Reliable |
| Natural Gas | No | Medium | Reliable |
| Solar | Yes | Very low | Weather dependent |
| Wind | Yes | Very low | Wind dependent |
| HEP | Yes | Low | Reliable if water available |
| Nuclear | No | Low emissions but hazardous waste | Very reliable |
8. Case Study: Energy Supply in Kenya
Country example: Kenya
Energy sources used
- Geothermal power
- Hydroelectric power
- Oil imports
- Wind energy
- Fuelwood and charcoal
Example: Geothermal Energy in Kenya
Location:
- Olkaria Geothermal Power Station
Reasons for development:
- Located in the Great Rift Valley with volcanic activity
- Reliable energy source
Benefits:
- Renewable
- Reduces dependence on imported oil
- Provides electricity for homes and industry
Problems:
- High development costs
- Environmental impacts such as land disturbance
9. Exam Tips for Energy Questions
1. Always classify energy
State whether the energy source is:
- Renewable
- Non-renewable
2. When asked for advantages/disadvantages
Give at least 3 points and explain them.
Example structure:
- Point
- Explanation
- Example (if possible)
3. Case study questions
You should remember:
- Location
- Energy type
- Reasons for development
- Benefits
- Problems
4. Use geographical terms
Important terms examiners like:
- Energy security
- Sustainable energy
- Carbon emissions
- Fossil fuels
- Renewable energy
- Energy demand
10. Key Terms to Memorize
Fossil fuel
Fuel formed from ancient organic matter (coal, oil, gas).
Renewable energy
Energy that can be naturally replaced.
Non-renewable energy
Energy that will eventually run out.
Hydroelectric power (HEP)
Electricity generated from flowing water.
Biofuel
Fuel made from plant or animal materials.
Energy demand
The amount of energy needed by people and industries.