Cambridge IGCSE Geography (0460): Theme 3.5 – Energy – Study Guide

This guide covers Topic 3.5 Energy from the Cambridge IGCSE Geography (0460) syllabus for examination in 2025 and 2026, Version 2 (published November 2022). Topic 3.5 sits in Theme 3, Economic development. It is examined in Paper 1 Geographical Themes (1 hour 45 minutes, 75 marks), where you answer three questions, one from each section. The syllabus also says Paper 2 Geographical Skills knowledge questions are based on topics from the three themes, and it lists energy among the things graphs in Paper 2 may show.

Use this guide with the energy revision notes and the energy practice questions. For the whole course, go to the Cambridge IGCSE Geography hub and tick off topics on the IGCSE Geography checklist.

Coverage table

Syllabus reference	What you must know or be able to do (from the document)	Where assessed
3.5	Describe the importance of non-renewable fossil fuels, renewable energy supplies, nuclear power and fuelwood, globally and in different countries at different levels of development	Paper 1; Paper 2 knowledge and graph items
3.5 guidance	Fossil fuels including coal, oil and natural gas	Paper 1
3.5 guidance	Renewable supplies including geothermal, wind, HEP, wave and tidal power, solar power and biofuels	Paper 1
3.5	Evaluate the benefits and disadvantages of nuclear power and renewable energy sources	Paper 1
3.5 case study	Energy supply in a country or area	Paper 1

The guidance column uses “including”, so you must study every source listed but may add others. The case study can come from anywhere in the world; your teacher will confirm which one your class uses.

Key terms

Term	Definition
Non-renewable energy	Energy from a stock that is used up and cannot be replaced within a human lifetime, such as coal, oil, natural gas and uranium
Renewable energy	Energy from a flow that is naturally replaced, such as wind, sunlight, moving water and heat from inside the Earth
Fossil fuel	A fuel formed over millions of years from the remains of plants and animals: coal, oil and natural gas
Fuelwood	Wood (and charcoal made from it) burned for cooking and heating
Nuclear power	Electricity generated using heat from splitting uranium atoms (fission)
HEP	Hydro-electric power: electricity generated by water flowing through turbines, usually from a dam
Geothermal energy	Heat from rocks below the surface, used directly for heating or to make steam for electricity
Biofuel	Fuel made from plant or animal material, such as ethanol from sugarcane
Energy mix	The share of a country’s energy that comes from each source
Intermittent	A supply that is not always available, such as solar at night or wind on calm days
Energy security	Having a reliable, affordable supply of energy, ideally not dependent on a single source or supplier

1. The importance of fossil fuels

Coal, oil and natural gas still supply most of the world’s energy. As of 2022, about 80% of world energy consumption came from fossil fuels. In 2024, coal and natural gas together still generated about 56.5% of world electricity, with coal alone at 34.4%.

Why they matter

• Coal is cheap and plentiful in countries such as China and India. It is mainly burned in power stations and in steel making.
• Oil is the main transport fuel (petrol, diesel, aviation fuel) and a raw material for plastics and chemicals.
• Natural gas is used for electricity, home heating and cooking. It releases less carbon dioxide than coal for the same energy.

At different levels of development. High-income countries use the most fossil fuel per person, for cars, heating and industry. Many emerging economies are increasing their use fastest as industry and cities grow. In many low-income countries, the main use is oil for transport and a few generators, because grid electricity reaches few rural homes.

Problems. Burning fossil fuels releases carbon dioxide, which drives enhanced global warming, and causes air pollution. Reserves will run out. Importing countries are exposed to price rises. These problems are the main reason countries look to nuclear and renewable sources.

2. The importance of fuelwood

Fuelwood is the main household fuel for many of the world’s poorest people. The World Health Organization says around 2.1 billion people, about a quarter of the world’s population, cook on open fires or inefficient stoves using kerosene, biomass (wood, animal dung and crop waste) or coal. Most live in low- and middle-income countries, and in 2021, 49% of the world’s rural population relied on these polluting fuels, compared with 14% in urban areas. About half of the wood taken from forests worldwide is used as fuelwood.

Why it is important in poorer countries: it is free or cheap to collect; there is no grid electricity in many villages; stoves need no imported fuel.

Problems: collecting wood takes hours, often for women and children; smoke indoors damages health (the WHO links household air pollution to an estimated 2.9 million deaths in 2021); cutting trees faster than they regrow causes deforestation and soil erosion.

Worked paragraph (Describe the importance). “Fuelwood is the main energy source for cooking in many rural areas of low-income countries (knowledge). In a village with no electricity grid, families collect wood from nearby woodland because it costs nothing (application). As the population grows, wood is cut faster than it regrows, so people must walk further and soil is left bare (analysis). Fuelwood is therefore important for survival, but it is not sustainable without tree planting or cleaner stoves (evaluation).”

3. Nuclear power

Nuclear power stations heat water by splitting uranium atoms. The steam drives turbines. In 2020, nuclear supplied about 4.3% of world primary energy, but some countries depend on it heavily.

Example: France. After the 1973 oil crisis, Prime Minister Pierre Messmer announced a large nuclear programme in March 1974. By 2018, nuclear produced about 72% of France’s electricity, the highest share in the world, and France has more than 50 operable reactors. France exports electricity to its neighbours. Its new reactor at Flamanville has cost several times the original estimate.

Benefits	Disadvantages
Very large, steady output whatever the weather	Very high cost and long building times
Very low carbon dioxide emissions when running	Radioactive waste stays dangerous for thousands of years and needs secure storage
Little fuel needed, so less dependence on imported oil and gas	Risk of serious accidents: Chernobyl, Ukraine (1986), and Fukushima Daiichi, Japan (2011, after an earthquake and tsunami)
Reliable base load supply for industry and cities	Public opposition; possible target for terrorism; needs cooling water, so often on coasts or rivers

Evaluation. Nuclear power suits high-income countries with money, skilled workers and strong safety regulators. It is rarely an option for low-income countries. Accidents are rare, but when they happen the effects are severe and long-lasting, which is why some countries, such as Germany, have shut their nuclear plants while others are building more.

Worked paragraph (Evaluate). “Nuclear power provides large amounts of low-carbon electricity (knowledge). France built most of its reactors after the 1973 oil crisis so that it would depend less on imported oil, and by 2018 nuclear made about 72% of its electricity (application). This cut emissions and gave a steady supply, but France must still store long-lived radioactive waste and pay rising costs for new reactors such as Flamanville (analysis). Nuclear power is a strong option for a wealthy country with good regulation, but its cost and waste make it less suitable for poorer countries (evaluation).”

4. Renewable energy sources

Hydro, wind and solar together supplied about 29% of world electricity in 2024: hydro 14.4%, wind 8.1% and solar 6.9%. Other renewables, such as bioenergy and geothermal, add a little more. Each source needs particular physical conditions.

Source	How it works and where it suits	Benefits	Disadvantages
Geothermal	Steam or hot water from hot rocks; plate boundaries and volcanic areas	Steady supply day and night; also heats homes directly	Only possible in a few areas; can release hydrogen sulphide; drilling is costly
Wind	Turbines on hills, coasts and offshore where winds are strong and steady	No fuel cost; quick to build; land below can still be farmed	Intermittent; visual and noise impact; can kill birds
HEP	Dam stores water, which flows through turbines; needs high rainfall, steady river flow and a deep, narrow valley	Large, controllable output; reservoir can supply water and control floods	Floods land and homes; traps sediment; very costly; damages river ecosystems
Wave	Floating or shore devices driven by waves on exposed coasts	Strong resource on windy coasts	Mostly at trial stage; storms damage equipment; small output
Tidal	Barrage or underwater turbines; needs a large tidal range, often in an estuary	Tides are predictable	Very few suitable sites; barrages change estuary habitats
Solar	Photovoltaic panels or mirrors; best in sunny, low-latitude, dry areas	Panels can be used on single homes far from a grid; costs have fallen	No output at night; less in cloudy seasons; large farms use land
Biofuels	Crops such as sugarcane fermented into ethanol, or waste turned into biogas	Can replace petrol in cars; uses local farm produce	Uses farmland that could grow food; may lead to forest clearance

Real examples to use

• Three Gorges Dam, China (HEP): on the Yangtze River, it can generate about 22,500 MW and was fully operating in 2012. Estimates of people displaced range from 1.13 million to about 1.4 million.
• La Rance, France (tidal): opened in 1966 in Brittany as the world’s first tidal power station, 240 MW. The barrage has caused silting of the estuary.
• Olkaria, Kenya (geothermal): in the Great Rift Valley. Kenya had about 892 MW of geothermal capacity in 2023 and was the first African country to build geothermal plants. This shows a lower-income country using a plate-boundary resource.
• Brazil (biofuel): the National Alcohol Program began in 1975, and since 2003 flex-fuel cars can run on any blend of petrol and sugarcane ethanol.

Worked paragraph (Evaluate a renewable). “HEP produces large amounts of electricity without burning fuel (knowledge). The Three Gorges Dam on the Yangtze can generate about 22,500 MW (application). However, building the reservoir displaced over a million people and traps sediment behind the dam, so the benefits for cities and industry came at a cost to local communities and the river (analysis). HEP is reliable and low-carbon, but large schemes have social costs that smaller schemes might avoid (evaluation).”

5. Energy at different levels of development

	Low-income countries	Middle-income / emerging	High-income countries
Energy use per person	Low	Rising fast	High
Main sources	Fuelwood and other biomass; some oil; HEP where rivers allow	Coal and oil, with growing renewables	Oil, gas, coal, nuclear and a growing share of renewables
Main issues	No grid in rural areas; health and deforestation from fuelwood	Air pollution from coal; meeting fast-rising demand	Reducing carbon emissions; replacing old power stations

Energy use per person rises with income. In 2018, the world average was 1.2 tonnes of oil equivalent per person, but the United States used 4.4 and India 0.4.

6. Case study: energy supply in Iceland

Setting. Iceland lies on the Mid-Atlantic Ridge, a constructive plate boundary, so it has many volcanic and geothermal areas. It also has high rainfall, glaciers and steep valleys, which give fast-flowing rivers for HEP.

Energy mix. In 2016, about 85% of Iceland’s primary energy came from domestic renewable sources: geothermal about 65% and hydropower 20%. Most of the rest was imported fossil fuel. In 2025, almost all its electricity was renewable: 70.5% from hydropower and 29.4% from geothermal. About 90% of homes are heated by geothermal energy. Fossil fuels are still imported for cars, ships, aircraft and fishing boats.

Key sites

• Hellisheiði near Reykjavík is a geothermal plant producing 303 MW of electricity and hot water for district heating. A system added in 2014 pumps gases back underground to reduce hydrogen sulphide pollution in the capital.
• Kárahnjúkar in east Iceland is a 690 MW HEP scheme built mainly to power Alcoa’s Fjarðaál aluminium smelter. Its main dam is 193 metres tall. The flooding of a large area of highland led to protests.

Why energy supply matters. Cheap renewable electricity has attracted power-hungry industry: in 2005, 72% of electricity went to industries such as aluminium smelting. Iceland produces about 55,000 kWh of electricity per person per year, compared with an EU average of under 6,000 kWh.

Evaluation. Iceland shows how physical geography decides which renewables a country can use. It also shows disadvantages: large reservoirs damage wilderness, geothermal plants release gases, and imported oil is still needed for transport. Its model cannot simply be copied by countries without plate-boundary heat or a small population.

Worked case-study paragraph. “Iceland gets almost all its electricity from renewable sources: in 2025, 70.5% came from hydropower and 29.4% from geothermal (knowledge). This is because it lies on the Mid-Atlantic Ridge, where heat near the surface supplies plants such as Hellisheiði, and because high rainfall and glaciers feed rivers used by schemes such as Kárahnjúkar (application). Cheap power has attracted aluminium smelters, but the 690 MW Kárahnjúkar scheme flooded highland and caused protests (analysis). Iceland’s supply is low-carbon and secure, yet it still imports oil for transport, so it is not fully renewable (evaluation).”

Common errors

• Calling nuclear power renewable. Uranium is a non-renewable stock, even though nuclear power is low-carbon.
• Writing “renewables are good for the environment” without naming a source. HEP, tidal and biofuels all have environmental costs.
• Forgetting fuelwood, which the syllabus names separately.
• Describing a source’s conditions vaguely. Say “a large tidal range” or “a deep, narrow valley with high rainfall”.
• Mixing up energy (all uses, including transport and heating) and electricity (one part of it). Iceland’s electricity is nearly all renewable; its total energy is not.
• Giving only benefits or only disadvantages when a question asks you to weigh them up, for example “To what extent …?” or “How far do you agree …?”.
• A case study with no figures or place names. Named plants, percentages and capacities earn the higher levels.

Where next

• Plate boundaries and geothermal areas are explained in earthquakes and volcanoes.
• River flow and valley shape, which matter for HEP, are in rivers; wave and tidal settings link to coasts.
• Fuel and power as a factor in factory location is covered in industry, and levels of development in development.
• Enhanced global warming from burning fossil fuels links to environmental risks of economic development; dams for HEP often also supply water.
• Condense this guide with the energy revision notes, then test yourself with the practice questions.

Official syllabus

This guide follows the Cambridge IGCSE Geography (0460) syllabus for examination in 2025 and 2026, Version 2 (published November 2022), Topic 3.5 Energy. Always check the current syllabus on the Cambridge International website, and your teacher will confirm which case study your class uses.