National & global energy resources

The photograph shows a camper van with a solar panel on its roof. The solar panel is made from lots of solar cells connected together.

The solar panel is connected to a battery. The solar panel receives energy from the Sun to charge the battery.

Describe how energy is transferred from the Sun’s energy store to the battery’s energy store.

The petrol engine can also be used to charge the battery of the camper van.

Give an advantage of using the solar panel instead of the petrol engine to charge the battery.

Do not refer to cost in your answer.

The surface of the solar panel is black.

Explain why black is a suitable colour for the solar panel.

The solar panel can charge the battery in the camper van with a maximum current of 15 A.

Calculate the minimum time to transfer 360 000 C of charge through the battery.

Use the formula

charge transferred = current × time

The photograph shows the tidal power station across the estuary of the river Rance in France.

The diagram shows a simplified view of the tidal power station.

At high tide, water is trapped behind the tidal barrier.

At low tide, the trapped water is released through the turbine shaft. This causes a turbine to spin, which generates electricity.

Give two advantages of generating electricity using tidal power.

Give two disadvantages of generating electricity using tidal power.

At low tide, water flows through the turbine shaft.

As the height of the trapped water in the river decreases, water falls through a height of 8.0 m to reach the turbine shaft.

Calculate the energy transferred from the gravitational store of the water when 1.0 kg of water flows through the turbine shaft.

Use the formula

change in gravitational potential energy = mass × g × height

The tidal power station has a maximum power output of 240 000 kW when water falls through a height of 8.0 m.

Calculate the mass of water flowing through the turbine shaft in 1 second when the power station is operating at maximum power.

Assume the power station is 100% efficient.

The photograph shows a wind turbine used for supplying energy on a large scale.

Describe a change in the turbine’s energy stores from when the turbine is at rest to when it is moving at full speed.

Describe a change in the turbine’s energy stores when the wind is blowing but the turbine moves at constant speed.

State the formula linking efficiency to useful energy output and total energy output.

The wind transfers 1.2 × 10⁶J of energy to the turbine.

The total mass of the turbine blades is 16 000 kg.

The wind causes the turbine blades to accelerate from rest to an average speed of 7.6 m/s.

Calculate the efficiency of the turbine.

This question is about generating electricity from renewable energy resources.

Photograph 1 shows a solar farm in the United Kingdom and photograph 2 shows a geothermal power station in Iceland.

(Source: © Marcin Jucha / Shutterstock)
(Source: © Javarman / Shutterstock)

Discuss the advantages and disadvantages of generating electricity using solar power and geothermal resources.

A student investigates how the amount of light affects the output voltage of a solar cell.

Photograph 3 shows how the student sets up their equipment.

The student varies the distance between the solar cell and the lamp and measures the output voltage of the solar cell at each distance.

The student’s results are shown below.

5 cm, 0.45 V 14 cm, 0.06 V

8 cm, 0.18 V 17 cm, 0.04 V

11 cm, 0.10 V 20 cm, 0.03 V

Draw a table showing the student’s results.

Give a control variable for the student’s investigation.

The student states that the solar cell could be used as a power source for the lamp.

They suggest that this would work if

• the solar cell is connected directly to the lamp

• the light from the lamp is used to produce the output power from the solar cell

Explain, with reference to the principle of conservation of energy, why the student’s suggestion would not work.

A hydroelectric power (HEP) station generates electricity from renewable energy resources.

State what is meant by the term renewable energy resource.

The diagram shows the design of a HEP station.

The turbine is connected to a generator, which generates electricity.

Describe the energy transfers involved in generating electricity in the HEP station.

The HEP station is located near a large wind farm.

Give one advantage of generating electricity using the HEP station rather than the wind farm.

Give one disadvantage of generating electricity using the HEP station rather than the wind farm.

The HEP station has an electric pump that can pump water from the lower lake back to the upper lake.

The pump can be powered using electricity generated by the wind farm.

Explain how the HEP station and wind farm can be used together to maximise the effectiveness of generating electricity.

This question is about different methods of generating electricity.

Natural gas can be burned to generate electricity.

Name the energy store that decreases when natural gas is burned.

Burning natural gas and the movement of water waves can both be used to generate electricity.

Discuss the advantages and disadvantages of these two methods of generating electricity.

Kori Nuclear Power Plant in South Korea is one of the world’s largest nuclear fission power stations.

The reactors at Kori use nuclear fission to generate electricity.

The products released during nuclear fission have high energy in their kinetic store.

Give a product of nuclear fission.

Give two disadvantages of using nuclear fission to generate electricity.

Kori has a maximum power output of 7.49 × 10⁹W.

State what is meant by the term power.

Calculate the minimum time taken for Kori to transfer 6.4710¹⁴J of energy.

The table lists four methods of generating electricity and four energy stores.

The energy store of the initial energy resource decreases when electricity is being generated.

Complete the table by placing one tick (✓) in each row to show which energy store decreases.

State which method of generating electricity in the table does not use a renewable energy resource.

State two disadvantages of using wind turbines to generate electricity.

The photographs show two large-scale electrical production methods

• a hydroelectric power (HEP) station

• a wind farm

(Source: © Bryan Busovicki/Shutterstock)
(Source: © Tom Buysse/Shutterstock)

Hydroelectric power station
Wind farm

Discuss the advantages and disadvantages of using hydroelectric power stations compared with wind farms for large-scale electricity production.

Describe the energy transfers that are involved in generating electricity in a hydroelectric power station.

The photograph shows the Three Gorges Dam in China, one of the largest hydroelectric power stations on Earth.

State two advantages of generating electricity using hydroelectric power stations.

Water is held in a reservoir on one side of the dam.

The water flows through turbines to a river on the other side of the dam.

The water level of the river is lower than the water level of the reservoir.

State which energy store of the water decreases as the water flows from the reservoir to the river.

How is energy transferred from the dam to homes and factories in China?

The Three Gorges Dam has a larger maximum output power than any other hydroelectric power station on Earth.

State what is meant by the term power.

The mean energy transferred by the dam each day is 9.710¹⁴ J.

Calculate the mean output power of the dam.

The maximum output power is 22 500 MW.

Which of these is the same as 22 500 MW?

Suggest why the Three Gorges Dam does not always operate at its maximum output power.

The bar chart gives information about how some of the electrical power in the United States of America (USA) was generated in the year 2018.

Most of the electricity generated in the USA uses non‑renewable energy resources.

State what is meant by the term non‑renewable.

Determine the percentage of electrical power generated using the non‑renewable energy resources shown on the bar chart.

In 2018, the USA generated more than half of its electrical power by burning fossil fuels.

Explain one way that burning fossil fuels can be harmful to the environment.

The mean total electrical power output of the USA in 2018 was 4.7610¹¹W.

Calculate the mean electrical power output from solar energy resources.

The mean total electrical power output of the USA in 2018 was 4.7610¹¹W.

A typical solar farm generates 250 W of electrical power for every 1.0 m² of land area used.

Calculate the amount of land area needed if the USA were to generate all of its electrical power using solar energy resources.

land area =_........ ²

The total land area of the USA is 9.8310¹²m².

Discuss whether the USA could generate all of its electrical power using solar energy resources.

The photograph shows a solar power farm.

Discuss the advantages and disadvantages of using solar power rather than fossil fuels to generate electricity.

Solar panels produce direct current (d.c.).

The National Grid in many countries operates on alternating current (a.c.).

Describe the difference between direct current (d.c.) and alternating current (a.c.).

Conventional power stations burn fuel in a furnace.

The fuel can be a solid, a liquid or a gas.

Describe the motion of particles in a solid, a liquid and a gas.

When the fuel is burned, energy is transferred from the fuel to the water.

The water boils and turns into steam.

Describe how energy stored in the fuel is transferred to the water.

Refer to energy stores and transfers in your answer.

The temperature-time graph shows how the temperature of the water changes as it is heated in the furnace at a constant rate.

Explain how the graph shows that the water changes state as it is heated.

This question is about energy resources.

The table lists some methods of generating electricity using energy resources.

Place ticks () in the table to show if each method uses a renewable energy resource. One has been done for you.

Solar cells can be used to generate electricity.

How is energy transferred from the Sun to a solar cell?

State one disadvantage of using solar cells to generate electricity.

The diagram shows a fossil fuel power station.

Five stages of electricity generation and transmission are shown.

furnace and boiler condenser turbines generator transformer

The power station burns a fossil fuel in the furnace.

Give an example of a fossil fuel.

Which stage of the power station transfers energy from a chemical store to a thermal store?

Which stage of the power station transfers energy electrically from a kinetic energy store?

Electricity can also be generated by solar farms.

Energy is transferred from the Sun to the solar farm by radiation.

The solar farm uses photovoltaic cells to transfer this energy electrically.

Discuss the advantages and disadvantages of generating electricity using solar farms.