P3 Revision

Question 1

What are Biofuels?

Answer 1

Involves transferring the fuel stored in biomass (trees, plants, or animal waste) into thermal energy to generate electricity.

Question 2

Biofuel advantages

Answer 2

• Renewable as long as the trees and plants are regrown, and the animal manure is continuously produced.
• Carbon-neutral as it doesn’t add to the greenhouse effect.
• Doesnt require specialised equipment and can be easily done.

Question 3

Biofuels disadvantages

Answer 3

• Large areas of land are required for regrowing trees and plants, and to allow enough animals to graze.

Question 4

What is nuclear power?

Answer 4

Nuclear power is the use of nuclear reactions to produce electricity. Involves splitting the nucleus of Uranium or Plutonium atoms to produce enough heat to generate electricity.

Question 5

Nuclear power advantages

Answer 5

• No greenhouse gases are emitted as no fuel is burned.
• Extremely energy efficient.

Question 6

Nuclear power disadvantages

Answer 6

• Lots of radioactive waste material is used and needs to be safely disposed.
• Possibility of accidental release of radioactive materials.
• Non-renewable as it uses radioactive fuels that are non-renewable resources.

Question 7

What are fossil fuels

Answer 7

Fossil fuels consist of coal, oil and natural gas. They are formed from the remains of dead organisms found beneath the Earth’s surface, and are burned as a fuel to produces electricity.

Question 8

Fossil fuel advantages

Answer 8

• Cheap to excavate.
• Can be easily transferred to different energy stores.

Question 9

Fossil fuel disadvantages

Answer 9

• Non-renewable.
• Releases greenhouse gases (carbon dioxide and sulfur dioxide) when burned.
• Finite in supply and will eventually run out.

Question 10

What is geothermal power?

Answer 10

Geothermal power involves using the natural heat from rocks deep beneath the Earth’s surface to generate electricity.

Question 11

Geothermal power advantages

Answer 11

• Renewable.
• No pollution as nothing is burned.
• Doesnt harm the environment.

Question 12

Geothermal power disadvantages

Answer 12

• Very few places in the world where this can be done.
• It is expensive to set up.

Question 13

What is tidal power?

Answer 13

Tidal power involves trapping water from each high tide behind a barrage and releasing it back into the oceon through turbines during low tide to produce electricity.

Question 14

Tidal power advantages

Answer 14

• Renewable.
• No pollution as nothing is burned.
• Reliable as there are always two tides per day.
• Easy to run once built.

Question 15

Tidal power disadvantages

Answer 15

• Expensive to build.
• Barrage malfunctions can cause local flooding.
• Can affect nearby habitats of wildlife.

Question 16

What is wind power?

Answer 16

Wind power uses the kinetic energy of natural winds to generate electricity.

Question 17

Wind power advantages

Answer 17

• Renewable.
• No pollution as nothing is burned.

Question 18

Wind power disadvantages

Answer 18

• Creates loud, disruptive noises.
• Considered unsightly and believed to ruin natural landscapes.
• Only works when it is windy.
• Large areas of land are required.

Question 19

What are solar cells and solar panels?

Answer 19

Solar cells involve using solar radiation from the sun to generate electricity.

Solar panels involve using solar radiation to heat water.

Question 20

Solar cells advantages

Answer 20

• Renewable.
• No pollution as nothing is burned.
• Expensive to buy but cheap to run with little maintenance.

Question 21

Solar cells disadvantages

Answer 21

• Transfers less than 10% of the sun’s energy absorbed into electricity.
• Only useful where small amounts of electricity are needed.
• Lots of solar cells and plenty of sunshine required.

Question 22

Nuclear power process

Answer 22

1. Nuetrons are fired at plutonium or uranium atoms in a chain reaction, producing heat.
2. Heat generated is used to boil water.
3. Boiled water produces steam
4. Steam energy is converted to electrical energy.

Question 23

Wind power process

Answer 23

1. As wind blows, some of its kinetic energy is transferred to the turbine blades, allowing them to spin around a rotor.
2. This dirves a generator, coverting kinetic energy into electrical energy.

Question 24

Hydroelectric power process

Answer 24

1. Water is stored in valleys behind dams.
2. The water is released and travels down pipes into the power station.
3. The waters potential energy coverts to kinetic energy.
4. The kinetic energy of the water turns the turbine blades.
5. As the turbines spins, the kinetic energy is transferred into electrical energy.
6. Once electricity is produced, the water is pumped back up to the dam to be reused.

Question 25

Tidal power process

Answer 25

1. Water is trapped from each high tide behind a barrage. 2. The water is released back into the ocean through turbines during low tide. 3. The turbines are spun due to the releasing water. 4. The spinning turbines coverts the water's gravitational potential energy into electrical energy.

Question 26

Solar power process

Answer 26

1. Sunlight is captured using solar panels, made up of solar cells. 2. When the sunlight hits the solar cells, an electric charge builds up within them, creating a flow of electricity.

Question 27

Geothermal power process

Answer 27

1. Cold water is pumped below the ground to the hot rocks beneath the Earth's surface. 2. The hot rocks heat the cold water, turning it into steam. 3. The steam returns to the surface into a power station where its energy is converted into electrical energy.