Chapter 3: Energy resources

Question 1

Energy demands

Answer 1

• Your energy demands are met mostly by burning oil, coal, gas
• Nuclear power, biofuel and renewable resources provide energy to generate some of the energy you use
• Uranium or plutonium is used as the fuel in nuclear power stations. Much more energy is released per kilogram from uranium or plutonium than fossil fuels
• Biofuels are renewable resources of energy. Biofuels such as methane and ethanol can used to generate electricity

Question 2

Energy from wind and water

Answer 2

• A wind turbine is an electricity generator on top of a tall tower
• Waves generate electricity by turning a floating generator
• Hydroelectric generators are turned by water running down a hill
• A tidal power station traps each high tide and uses it to turn generators

Question 3

Power from the sun and the earth

Answer 3

• Solar cells are flat solid cells and use the suns energy to generate electricity directly
• Solar heating panels use the sun’s energy to heat water directly
• Geothermal energy comes from the energy transferred by radioactive substances deep inside the earth
• Water pumped down into hot rocks produces steam to drive turbines at the earth’s surface that generate electricity

Question 4

Energy and the environment

Answer 4

• Fossil fuels produce increased levels of greenhouse gases
• Nuclear fuels produce radioactive waste
• Renewable energy resources will never run out, they do not produce harmful waste products, and they can be used in remote places. But they cover large areas and they can disturb natural habitats
• Different energy resources can be evaluated in terms of reliability, environment effects, pollution and waste

Question 5

Big energy issues

Answer 5

• Gas fired power stations and pumped-storage stations can meet variations in demand
• Nuclear power stations are expensive to build, run and decommission.
• Carbon capture of fossil fuel emission is likely to be expensive.
• Renewable resources are cheap to run but expensive to install.
• Nuclear power stations, fossil fuel power stations that use carbon capture technology, and renewable energy resources are likely to be needed for future energy supplies