Welcome! In this lesson you’re going to find out where our electricity comes from, decide which energy resources are best, and practise real exam questions. It takes about one hour. Work through the steps in order – don’t skip ahead.
Before you start
- You need: paper or your exercise book and a pen.
- Write the title and date at the top of your page: Energy resources – Power the Island.
- The golden rule: always write your answer first, then tap Show answer to check. Tick what you got right and correct anything you got wrong in a different colour.
- Look out for the blue 📝 boxes. Whenever you see one, copy it into your book neatly – these are your notes for revision.
📝 Copy into your book
By the end of this lesson I will be able to:
1. name the main energy resources and say which are renewable
2. compare them for reliability and their effect on the environment
3. answer a “compare” and an “evaluate” exam question.
Step 1: Starter (5 minutes)
Think about the last time you plugged your phone in to charge. The energy didn’t start at the plug socket – so where did it come from?
Your task: trace the energy back as far as you can. Write it as a chain of arrows, starting from the plug socket. Try to get at least 4 steps.
Stuck? Think: what’s at the other end of the cables? What turns a generator?
Show answer
Plug socket ← National Grid cables ← generator at a power station ← turbine turned by steam, wind or water ← energy resource (e.g. gas burned to boil water, or the wind).
The big question for this lesson is: which resource should we use?
📝 Copy into your book
Most power stations use an energy resource to turn a turbine, which turns a generator to make electricity.
✅ Move on when you’ve checked your chain and copied the box.
Step 2: Read and write (12 minutes)
First, copy these three questions into your book. Then read the text below carefully and answer them in full sentences.
- How do fossil fuel power stations make electricity?
- Give two problems with burning fossil fuels.
- Pick two renewable resources. For each, write one advantage and one disadvantage.
📖 Read: Where does our electricity come from?
Fossil fuels – coal, oil and gas – are burned in power stations. The energy released heats water to make steam. The steam turns a turbine, which turns a generator to make electricity. Fossil fuels are reliable, but burning them releases carbon dioxide, which contributes to climate change, and sulfur dioxide, which causes acid rain. They will also run out one day.
Renewable resources won’t run out. Wind turbines produce no carbon dioxide while generating, but they only work when the wind blows and some people think they spoil the view. Solar cells produce no emissions, but give no electricity at night and less on cloudy days. Hydro-electric dams are reliable and can be switched on quickly, but flooding a valley destroys habitats. Tidal barrages are predictable, but they change estuary habitats. Geothermal power stations use hot rocks underground, but only work in a few places.
Show answers
(a) The fuel is burned to heat water into steam, which turns a turbine connected to a generator.
(b) Any two: they release carbon dioxide (which contributes to climate change); they release sulfur dioxide (acid rain); they will run out.
(c) For example: wind – no fuel and no emissions, but unreliable when the wind drops; solar – no emissions, but no output at night.
📝 Copy and complete
Burning fossil fuels releases __________ __________, a greenhouse gas that contributes to __________ __________. It also releases __________ __________, which causes acid rain.
Check your gaps
carbon dioxide · climate change · sulfur dioxide
✅ Move on when you’ve answered all three questions and completed the box.
Step 3: Sort it (5 minutes)
First, two key words. Copy them carefully – they’re worth marks in the exam.
📝 Copy into your book
Renewable resource: one that is being (or can be) replenished as it is used, so it will not run out.
Non-renewable resource: one that will run out, because it is not replaced as fast as it is used.
Your task: draw two columns labelled Renewable and Non-renewable. Put each of these resources in the right column:
coal · wind · nuclear fuel · solar · oil · tidal · gas · hydro-electricity · bio-fuel · geothermal · water waves
Stuck? Ask yourself: “Could we ever run out of this?”
Show answer
Non-renewable (4): coal, oil, gas, nuclear fuel.
Renewable (7): wind, solar, tidal, hydro-electricity, bio-fuel, geothermal, water waves.
Watch out: lots of people think nuclear is renewable – it isn’t! The uranium it uses will run out.
✅ Move on when you’ve got all 11 in the right place.
Step 4: Fact cards (10 minutes)
Now you’re going to build a comparison table – you’ll need it for the main task. First, one more key word:
📝 Copy into your book
Reliable: it can generate electricity whenever it is needed.
Your task: copy this table into your book, with 9 empty rows. Then tap each card below and fill in one row for each resource. Keep your answers short – a few words in each box is enough.
| Resource | Renewable? | Reliable? | CO₂ when generating? | Other effects |
|---|---|---|---|---|
| e.g. Wind | Yes | No – needs wind | None | Noisy, spoils view |
Fossil fuels: coal, oil and gas
How: burned to heat water; steam turns a turbine. Renewable? No – will run out. Reliable? Yes – available whenever needed. CO₂? Yes – contributes to climate change; also sulfur dioxide (acid rain). Other: also used for transport (oil) and heating homes (gas).
Nuclear fuel
How: nuclear fission releases energy that heats water into steam. Renewable? No. Reliable? Yes. CO₂? None while generating. Other: radioactive waste must be stored safely for a very long time; small risk of a major accident; very expensive to build and to shut down.
Wind
How: wind turns the blades, which turn a generator. Renewable? Yes. Reliable? No – depends on wind speed. CO₂? None while generating. Other: noise and visual impact; lots of turbines needed.
Solar
How: solar cells turn sunlight directly into electricity. Renewable? Yes. Reliable? No – nothing at night and less when cloudy. CO₂? None while generating. Other: big solar farms use a lot of land; great for remote places.
Hydro-electricity
How: water stored behind a dam flows down through turbines. Renewable? Yes. Reliable? Yes – and it can be switched on very quickly when lots of people need electricity at once. CO₂? None while generating. Other: flooding a valley destroys habitats and can force people to move.
Tides
How: a barrage (wall) across an estuary traps water at high tide and lets it out through turbines. Renewable? Yes. Reliable? Predictable, but the amount changes during the day. CO₂? None while generating. Other: expensive; changes the estuary habitat for wildlife.
Water waves
How: the up-and-down movement of waves drives a generator. Renewable? Yes. Reliable? No – depends on the weather. CO₂? None while generating. Other: can affect sea life and boats.
Geothermal
How: hot rocks underground heat water into steam. Renewable? Yes. Reliable? Yes. CO₂? Very little. Other: only works in a few places where hot rocks are near the surface (e.g. Iceland).
Bio-fuel
How: plant material or animal waste is burned, like a fossil fuel. Renewable? Yes – plants can be regrown. Reliable? Yes. CO₂? Yes when burned, but the plants took in carbon dioxide while they were growing. Other: uses land that could grow food; forests may be cut down.
✅ Move on when your table has all 9 rows filled in.
Step 5: Quick check (5 minutes)
Let’s see what’s stuck! Cover your table and answer these from memory. Only look back if you really can’t remember – and make a note of which ones you needed help with.
Q1 Name the three fossil fuels.
Show answer
Coal, oil and (natural) gas.
Q2 Why is nuclear fuel non-renewable?
Show answer
The uranium it uses is mined and will run out – it isn’t replaced as we use it.
Q3 Which renewable resource can be switched on quickly when lots of people suddenly need electricity?
Show answer
Hydro-electricity.
Q4 Why is tidal power more reliable than wind power?
Show answer
Tides happen every day at times we can predict; the wind depends on the weather.
Q5 Give one problem that hydro-electric dams cause for the environment.
Show answer
Flooding a valley destroys habitats (and may force people to move).
Q6 Why don’t we use geothermal power everywhere?
Show answer
It only works where hot rocks are close to the surface, which is only in a few places.
📝 Copy and complete
Wind and solar power are unreliable because __________ and __________. Hydro-electricity is useful because it can be __________ __________ __________ when demand suddenly rises.
Check your gaps
the wind doesn’t always blow · there is no sunlight at night · switched on quickly
✅ Count your score out of 6. 5 or 6? Brilliant. 4 or less? Re-read the cards for the ones you missed before moving on.
Step 6: Main task – Power the Island (10 minutes)
You’ve been hired as the island’s energy adviser!
A small island gets all its electricity from diesel generators. The diesel has to be shipped in by boat and costs £6 million a year. The island is very windy and gets lots of sunshine.
The island council has £80 million to spend. They have three goals:
- Cut carbon dioxide emissions.
- Cut the yearly running costs.
- Keep the lights on at all times – day and night.
Here are the options. You can choose more than one, as long as the total cost to build is no more than £80 million.
| Option | Cost to build | Running cost per year | Reliable? | CO₂ when generating | Other |
|---|---|---|---|---|---|
| Wind farm | £45 million | £1 million | No – depends on wind | None | Noise, visual impact, birds |
| Solar farm | £20 million | £0.5 million | No – none at night | None | Uses farmland |
| Tidal barrage | £90 million | £1 million | Predictable | None | Damages estuary habitat |
| Undersea cable to the mainland grid | £60 million | £3 million (buying electricity) | Yes | Depends on how the mainland makes its electricity | Cable could be damaged by storms |
| Keep the diesel generators | £0 (already built) | £6 million if used all the time | Yes | High | Fuel must be shipped in |
First, copy the writing frame – you’ll use it for exam questions too:
📝 Copy into your book
How to evaluate:
FOR – at least 2 reasons, using data
AGAINST – at least 2 problems
JUDGEMENT – “Overall, the best choice is… because…”
Your task: now write your advice to the council using the frame. Start with My choice: which option(s) and the total cost.
Stuck? Check each option against the three goals. Which one keeps the lights on when there’s no wind and no sun?
Show a model answer
My choice: wind farm + solar farm (£45m + £20m = £65 million), keeping the diesel generators as a backup.
For: both are renewable and produce no carbon dioxide when generating, so emissions fall a lot. Running costs are only £1.5 million a year, compared with £6 million for diesel. The island is windy and sunny, and wind and solar often work at different times, so together they cover more of the day.
Against: neither is reliable – solar gives nothing at night and wind drops on calm days – so diesel is still needed sometimes. The turbines cause noise and visual pollution, and the solar farm uses farmland.
Judgement: overall, this is the best choice because it cuts CO₂ and running costs the most while staying within budget, and the diesel backup keeps the lights on. The tidal barrage is too expensive (£90 million).
Chose something different? That’s fine! For example, the cable + solar farm (£80 million) is reliable, but its CO₂ depends on how the mainland makes electricity and it costs more to run. Any choice can be a great answer if you use the data and finish with a clear judgement.
✅ Check your answer: did you use numbers from the table? Did you give reasons against? Did you finish with a judgement? Add anything you missed.
Step 7: Exam practice (11 minutes)
Time to try some real exam-style questions. First, copy these two command words – they tell you exactly what the examiner wants.
📝 Copy into your book
COMPARE = talk about both options in every point. Use the word “whereas”.
EVALUATE = give points for and against, then a judgement.
Look at the marks – they tell you how many points to make. Write in full sentences, then compare with the model answer and give yourself a mark.
Q1 (2 marks) Explain why a town cannot rely on a solar farm as its only supply of electricity.
Hint: 2 marks = say what the problem is, then what it causes.
Show model answer
Solar cells produce no electricity at night (and less when it is cloudy) (1), so the town would have no supply at times when it still needs electricity – another, reliable source is needed (1).
Q2 (4 marks) A country could build either a gas power station or an offshore wind farm. Both have a maximum output of 800 MW.
| Gas power station | Offshore wind farm | |
|---|---|---|
| Average output | 90% of maximum | 40% of maximum |
| When it can generate | Whenever needed (starts in about 1 hour) | Only when windy |
| Fuel | Gas must be bought | None |
| CO₂ when generating | Yes | None |
Compare the two options.
Hint: “compare” – check your 📝 box! Try one point for each row of the table.
Show model answer
The gas power station’s average output is 720 MW (90%), whereas the wind farm’s is only 320 MW (40%) (1). The gas station can generate whenever it’s needed, whereas the wind farm only generates when it is windy, so it is less reliable (1). The gas station has to buy fuel and uses a non-renewable resource, whereas wind is free and renewable (1). The gas station releases carbon dioxide, which contributes to climate change, whereas the wind farm releases none when generating (1).
Did you notice? Working out 90% and 40% of 800 MW turned the data into real numbers – examiners love that.
Q3 (6 marks – Higher) Some people want to replace the UK’s remaining fossil fuel power stations with nuclear power stations. Evaluate this plan.
Hint: “evaluate” – use your frame from Step 6. Aim for about 3 points for, 3 against, and a clear judgement. Use “…so…” to explain each point.
Show model answer
For: nuclear power stations release no carbon dioxide when generating, so replacing fossil fuels would reduce emissions and climate change. They also release no sulfur dioxide, so there would be less acid rain. Like fossil fuel stations, they are reliable, so they can provide electricity at any time, unlike wind or solar.
Against: nuclear fuel is non-renewable, so it will eventually run out. It produces radioactive waste, which must be stored safely for a very long time. There is a small risk of a major accident. Nuclear power stations are very expensive and take many years to build and to shut down. They can’t be switched on quickly when demand suddenly rises.
Judgement: e.g. “Overall it is a good plan for reliable, low-carbon electricity, but it should be combined with renewables and hydro-electricity to meet changing demand and reduce the amount of waste.”
To get top marks you need: points for and against, each explained with “…so…”, and a clear judgement at the end.
✅ Add up your marks out of 12 (or out of 6 if you’re doing Foundation and skipped Q3). Write your score at the bottom of your page.
Step 8: Exit ticket (2 minutes)
Nearly done! Finish these three sentences in your book:
- The most important thing I learned today is…
- If I were in charge of the UK’s electricity, I would use… because…
- One thing I’m still not sure about is…
🎉 Well done – you’ve finished the lesson! Look back at your 📝 boxes – they’re your revision notes for this topic.
Want to go further?
Try the Energy resources questions and the Long-answer questions (Q6 and Q7 are about energy resources).
▶ Want to watch a video on this topic? (optional)
These are extra – you don’t need them for any of the questions above.
🖨️ Want this lesson on paper? Download the whole lesson as a printable worksheet – answers are on the last page.
