AQA GCSE Physics 8463: National and global energy resources – Revision Notes

These are condensed recall notes for section 4.1.3 National and global energy resources of the AQA GCSE Physics (8463) specification, Version 1.1 (30 September 2019), for teaching from September 2016 and exams from 2018 onwards. Topic 1 Energy is assessed on Paper 1, set at Foundation and Higher Tier. Nothing in 4.1.3 is marked (HT only), so every line here applies to both tiers.

For fuller explanations, use the National and global energy resources study guide. Then test yourself with the energy resources practice questions. The rest of Topic 1 is in the Energy changes in a system revision notes and the Conservation and dissipation of energy revision notes. The course hub is AQA GCSE Physics, the printable checklist lists every point, and the free diagnostics help you find weak topics.

What 4.1.3 asks you to do

The specification says you should be able to…	What that means in an answer
describe the main energy sources available	Name each resource and say what it is
distinguish renewable from non-renewable	Classify each one and justify with the definition
compare ways resources are used (transport, electricity generation, heating)	Say which resources suit which use, and why
understand why some resources are more reliable than others	Link reliability to weather, time of day, season or fuel supply
describe the environmental impact of using different resources	Name a specific impact and its cause
explain patterns and trends in the use of resources	Read data, quote numbers, then give reasons
consider environmental issues from the use of resources	Weigh impacts for a given situation, using data
show that science can identify issues but cannot always deal with them	Name the political, social, ethical or economic barrier

The specification also says: descriptions of how energy resources are used to generate electricity are not required.

Definitions

• Renewable energy resource: one that is being (or can be) replenished as it is used.
• Non-renewable energy resource: one that is not replenished as it is used. Supplies are finite, so it will eventually run out.

Justify with the definition: “Bio-fuel is renewable because new crops can be grown as it is used.”

The main energy resources

The specification lists eleven: fossil fuels (coal, oil and gas), nuclear fuel, bio-fuel, wind, hydro-electricity, geothermal, the tides, the Sun and water waves.

Resource	Renewable?	What it is, in one line
Coal	No	Fossil fuel burned to release energy from its chemical store
Oil	No	Fossil fuel; refined into petrol, diesel and heating oil
Gas (natural gas)	No	Fossil fuel burned in power stations, boilers and cookers
Nuclear fuel	No	Uranium or plutonium; energy released from the nuclear store
Bio-fuel	Yes	Fuel from plants or animal waste (e.g. wood, bioethanol, biodiesel)
Wind	Yes	Moving air turns wind turbines
Hydro-electricity	Yes	Water falling from a reservoir behind a dam
Geothermal	Yes	Energy from hot rocks underground
Tides	Yes	Rise and fall of sea level, caused mainly by the Moon
Sun (solar)	Yes	Solar cells make electricity; solar panels heat water
Water waves	Yes	Up-and-down motion of waves at the sea surface

Nuclear fuel is not a fossil fuel, but it is non-renewable. Keep the two ideas apart.

Uses: transport, electricity generation, heating

Use	Resources commonly used	Note
Transport	Petrol and diesel (from oil); bio-fuels; electricity for electric cars and trains	A fuel for vehicles must be portable and store a lot of energy
Electricity generation	Every resource on the list can be used	Electricity is then transferred to homes and industry
Heating	Gas, oil, coal and wood burned in homes; electric heaters; solar water heating; geothermal	Heating can use a fuel directly, or use electricity

Method in steps: “compare how two resources are used”

1. Name the use(s) each resource is suited to.
2. Give a reason for each, linked to a property (portable, available on demand, location).
3. Make an explicit comparison word: “whereas”, “but”, “more”, “less”.

Worked reminder. Oil gives petrol and diesel, liquid fuels a vehicle carries in its tank. Wind cannot be carried, so it powers transport only by generating electricity for electric vehicles. Oil is used directly, whereas wind is used only through electricity.

Reliability

A resource is reliable if it can supply energy whenever it is needed, or if its output is predictable.

Resource	Reliability	Why
Fossil fuels	Reliable	Available whenever needed, as long as fuel is supplied
Nuclear fuel	Reliable	Runs steadily all the time while fuel is supplied
Bio-fuel	Reliable	Can be stored and burned when needed
Geothermal	Reliable	Hot rocks are always there; output steady
Hydro-electricity	Reliable while the reservoir holds water	Output can be started quickly; a long dry spell reduces supply
Tides	Predictable, but output varies	Tides come in and out at known times; output varies with the tides through the day
Wind	Unreliable	No output on still days; output varies with wind speed
Sun	Unreliable	Nothing at night; less on cloudy days and in winter
Water waves	Unreliable	Wave height depends on the weather

Must-know distinctions

• Renewable is not the same as reliable. Wind is renewable but unreliable; coal is reliable but non-renewable.
• Renewable is not the same as harmless. Hydro-electric dams and tidal barrages are renewable but change habitats.
• Tides vs waves. Tides are predictable (driven mainly by the Moon). Waves depend on the weather.
• Hydro vs tidal. Hydro uses river water stored behind a dam on land. Tidal uses the rise and fall of the sea.
• Source vs use. “Electricity” is not an energy resource. It is produced from a resource.

Environmental impact

Name the impact and its cause. “Bad for the environment” earns nothing.

Resource	Main environmental impacts
Coal, oil, gas	Burning releases carbon dioxide, which contributes to global warming and climate change. Coal and oil also release sulfur dioxide, which causes acid rain. Oil spills harm sea life; mining and drilling damage landscapes
Nuclear fuel	No carbon dioxide released while running, but produces radioactive waste that must be stored safely for a very long time; risk of a serious accident
Bio-fuel	Releases carbon dioxide when burned, though growing the plants absorbs carbon dioxide; land used for fuel crops can destroy habitats or reduce land for food
Wind	Visual impact and noise near turbines; can harm birds
Hydro-electricity	Flooding a valley destroys habitats and can displace people; rotting plants in the flooded area can release methane and carbon dioxide
Tides	A barrage changes the estuary habitat for birds and fish and can affect shipping
Sun	Large solar farms take up land; visual impact
Water waves	Equipment can disturb marine habitats and be a hazard to boats; visual impact
Geothermal	Little impact, but only possible in a few places

Patterns and trends

Method in steps: “explain the trend”

1. Describe the trend, using words such as increased, decreased, stayed roughly the same.
2. Quote numbers from the data (values or percentages), with units.
3. Explain with a reason for each change.

Reasons you can use:

• Use of fossil fuels for electricity in the UK has fallen because of concern about carbon dioxide and climate change, government targets to cut emissions, and because fossil fuels will run out. Britain’s last coal-fired power station, Ratcliffe-on-Soar, closed on 30 September 2024.
• Use of renewables such as wind and solar has risen for the same reasons.
• World energy use has increased because the world population is growing and more countries are industrialising, with people using more energy per person.

Worked reminder: reading a data table

The table shows invented data for electricity generated in a country in two years.

Resource	2005 (TWh)	2025 (TWh)
Coal	80	0
Gas	100	75
Nuclear	50	40
Wind	10	75
Solar	0	25
Other renewables	10	35
Total	250	250

Fossil fuels, 2005:  (80 + 100) / 250 × 100 = 72%
Fossil fuels, 2025:  (0 + 75) / 250 × 100   = 30%
Renewables, 2005:    (10 + 0 + 10) / 250 × 100  = 8%
Renewables, 2025:    (75 + 25 + 35) / 250 × 100 = 54%
Wind grew by a factor of 75 / 10 = 7.5

A full answer: “The fossil fuel share fell from 72% to 30%, and coal fell to zero. The renewable share rose from 8% to 54%, with wind growing 7.5 times. Total generation stayed at 250 TWh, so renewables replaced fossil fuels rather than meeting extra demand, probably to cut carbon dioxide emissions.” Always calculate percentages from the totals given.

Science identifies issues but cannot always solve them

Scientists can link carbon dioxide to climate change and assess the risks of radioactive waste. Whether anything is done depends on other factors.

Consideration	Examples
Economic	Building nuclear or tidal power stations costs a lot; fossil fuel stations already exist; cost of energy to consumers
Political	Governments set targets and policy; international agreement is needed; energy security (relying on imported fuel)
Social	Local people may object to wind farms near their homes; jobs in coal mining or power stations may be lost
Ethical	Should we leave radioactive waste and climate change for future generations? Is it fair to ask poorer countries to use less energy?

In an answer, name the type of consideration and give a specific example of it.

Quick self-test

1. Use the definition to explain why wood is a renewable resource.
2. Name the renewable resource that gives a steady output but is only available in a few places.
3. Which is more predictable, tidal power or wave power? Give a reason.
4. Name two energy resources used directly to heat homes.
5. Name one renewable resource used as a fuel for transport.
6. Give one environmental impact of building a hydro-electric dam that floods a valley.
7. Burning coal releases sulfur dioxide. Name the environmental problem this causes.
8. A country generates 240 TWh of electricity in a year. 54 TWh comes from wind. What percentage is this?
9. Solar generation in a country rose from 18 TWh to 54 TWh. By what factor did it increase?
10. Solar provides 5% of a country’s 300 TWh of electricity. How much electricity is this?
11. Give one reason why world energy use has increased.
12. Scientists agree that burning fossil fuels contributes to climate change. Give two reasons, other than scientific ones, why some countries still build fossil fuel power stations.

Answers

1. Trees can be replanted and grown again, so wood can be replenished as it is used.
2. Geothermal.
3. Tidal. Tides happen at known times each day; waves depend on the weather.
4. Any two of: gas, oil, coal, wood (bio-fuel), the Sun (solar water heating), geothermal.
5. Bio-fuel (for example bioethanol or biodiesel).
6. Any one: habitats are destroyed; people may have to move; rotting plants release methane or carbon dioxide.
7. Acid rain.
8. 54 ÷ 240 × 100 = 22.5%.
9. 54 ÷ 18 = 3 (it trebled).
10. 0.05 × 300 = 15 TWh.
11. The world population is growing, or more countries are industrialising and using more energy per person.
12. Any two, each named and specific: economic (fossil fuel stations are cheaper to build, or the fuel is available locally); political (energy security, or no international agreement); social (jobs in the fuel industry); reliability (they supply electricity on demand).

Where marks are usually lost

• Saying a renewable resource “never runs out” without the specification idea of being replenished as it is used.
• Calling nuclear fuel a fossil fuel, or calling it renewable because it releases no carbon dioxide.
• Treating “renewable” and “reliable” as the same thing in a comparison question.
• Writing “pollution” or “bad for the environment” instead of naming carbon dioxide, sulfur dioxide or radioactive waste and its effect.
• Mixing up tidal and wave power, or describing tidal power as unpredictable.
• Describing how a power station works when the question asks about the resource.
• Describing a trend without quoting numbers from the data, or quoting numbers without units.
• Working out a percentage from the wrong year’s total.
• On “explain why the issue has not been solved”, repeating the scientific problem instead of naming a political, social, ethical or economic barrier.

Official syllabus

AQA GCSE Physics (8463) specification, Version 1.1, 30 September 2019, for teaching from September 2016 and exams from 2018 onwards (AQA), section 4.1.3 National and global energy resources.