Evaluate — 5 marks
A small coastal town is considering two options to generate electricity for the next 20 years. Option A is to build a new coal-fired power station. Option B is to install offshore wind turbines. The town council must decide which option to pursue based on energy security, environmental impact, and cost.
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(a) Describe one advantage of using coal as an energy resource for this town.
[1 mark]
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(b) Describe one disadvantage of using coal as an energy resource.
[1 mark]
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(c) Evaluate which energy resource, coal or wind, would be more suitable for this coastal town. You should consider environmental impact, reliability, and sustainability in your answer.
[3 marks]
Show mark scheme
- (a) Coal is a reliable/dispatchable energy source that can generate electricity whenever needed
- (a) Coal power stations can be built on land already available in the town
- (a) Coal is currently an established technology with existing infrastructure
- (a) Coal provides a large amount of energy from relatively small amounts of fuel
- (b) Burning coal releases carbon dioxide/greenhouse gases contributing to climate change
- (b) Coal combustion produces air pollution/particulates that harm human health
- (b) Coal is a finite/non-renewable resource that will eventually run out
- (b) Coal mining damages the landscape/causes environmental degradation
- (c) Wind is more sustainable as it is renewable and will not run out (1 mark)
- (c) Wind turbines produce no greenhouse gases or air pollution during operation, better for the environment (1 mark)
- (c) However, wind is unreliable/intermittent as it depends on weather conditions, whereas coal provides constant power (1 mark)
- (c) For a coastal location, wind turbines are suitable as there is consistent wind resource (1 mark)
- (c) Wind has lower running costs but higher initial capital costs compared to coal (1 mark - accept if evaluative tone maintained)
Suggest — 4 marks
A small island nation currently relies on imported fossil fuels for 85% of its electricity generation. The government is planning a transition to renewable energy sources over the next 20 years. The island has consistent strong winds, significant tidal ranges, and limited suitable land for large-scale solar farms. The population is growing and energy demand is expected to increase by 40% within this period.
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(a) Suggest which renewable energy resource would be most suitable for this island's electricity generation and explain your choice.
[2 marks]
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(b) Suggest two reasons why a mixed renewable energy approach (using more than one renewable resource) would be advantageous for this island's future energy security.
[2 marks]
Show mark scheme
- (a) Wind energy (or tidal energy) identified as most suitable renewable resource (1 mark)
- (a) Valid reasoning such as: consistent strong winds provide reliable/predictable energy supply; tidal energy has high energy density and predictable patterns; these resources are not dependent on weather variability like solar; suitable for island geography/location (1 mark)
- (b) Reduces dependence on single energy source; if one renewable resource fails/underperforms, others can compensate/maintain supply (1 mark)
- (b) Different renewable sources have different peak generation times; wind and tidal can generate at different times, providing more consistent/continuous electricity supply throughout day/year; matches varying demand patterns (1 mark)
Suggest — 4 marks
A remote island community currently relies entirely on diesel generators for electricity. The island experiences consistent strong winds and receives significant rainfall throughout the year. The local government is considering transitioning to renewable energy sources to reduce costs and environmental impact, but faces challenges including limited storage capacity, geographical isolation, and a population that is hesitant about new technology.
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(a) Suggest why wind energy would be a more suitable renewable resource than solar energy for this island.
[1 mark]
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(b) The island's rainfall could be used for hydroelectric power. Suggest two reasons why this approach might be limited in effectiveness for meeting the island's total energy demand.
[2 marks]
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(c) Suggest how a combination of wind, hydroelectric, and diesel power could help overcome the energy storage limitation and encourage community acceptance of the renewable transition.
[1 mark]
Show mark scheme
- (a) Wind is more consistent/reliable than solar (island has consistent strong winds)
- (a) Solar intensity is reduced by cloud cover/rainfall typical of the island
- (a) Wind turbines can generate power during day and night/in cloudy conditions
- (b) 1 mark: Small/remote islands typically have limited height differences/topography unsuitable for large-scale hydroelectric schemes
- (b) 1 mark: Rainfall may be seasonal/variable, making output unpredictable/insufficient year-round
- (c) Diesel generators can act as backup/fill gaps when wind and hydroelectric output is low, reducing need for expensive battery storage
- (c) Gradual transition demonstrates reliability of renewables, building community confidence before full transition
- (c) Hybrid system allows flexible operation and proves renewable feasibility without complete overnight change
Calculate — 2 marks
A family installs solar panels on their house roof to reduce their use of electricity from the National Grid. The solar panels have a total power output of 3.5 kW when operating at maximum capacity. On a sunny day, the solar panels operate at maximum capacity for 4 hours.
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(a) Calculate the energy transferred by the solar panels in kilowatt-hours (kWh).
[1 mark]
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(b) The cost of electricity from the National Grid is 30 pence per kWh. Calculate how much money the family saves by using the solar panels instead of buying electricity from the National Grid.
[1 mark]
Show mark scheme
- (a) 3.5 × 4 = 14 (kWh)
- (a) or correct working shown with answer
- (b) 14 × 30 = 420 (pence)
- (b) or £4.20
- (b) or correct calculation using their value from 01.1
Explain — 3 marks
A small coastal town currently gets most of its electricity from a coal-fired power station. The local council is considering building offshore wind turbines instead to reduce pollution.
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(a) Explain one advantage of using wind turbines instead of coal to generate electricity.
[1 mark]
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(b) Explain why some people might object to building wind turbines offshore near the town.
[2 marks]
Show mark scheme
- (a) Wind is renewable / will not run out (unlike coal)
- (a) Wind turbines do not produce carbon dioxide/greenhouse gases (which contribute to climate change)
- (a) Wind turbines do not produce sulfur dioxide (which causes acid rain)
- (a) Wind turbines do not produce particulates (which cause respiratory problems)
- (a) Wind is free (whereas coal must be bought/mined)
- (b) Wind is unreliable / intermittent / depends on weather (whereas coal can be burned continuously)
- (b) Wind turbines are expensive to build / install
- (b) Wind turbines may spoil the view / visual pollution
- (b) Wind turbines may affect tourism
- (b) Wind turbines can be noisy
- (b) Wind turbines may harm birds/bats
GCSE Perfect