P3SUSTAINABLE

ENERGYLesson 11: Choosing the best energy

source

OBJECTIVES MUST state the advantages and

disadvantages of different energy sources

SHOULD interpret and evaluate information about energy sources

KEY WORDS You need to be able to define the following:

Power output

TEXTBOOK ANSWERS1) Biofuel2) Reduces greenhouse gas emissions and

other forms of pollution; reduces deaths due to their extraction; reduces damage to environment.

3) Nuclear power stations are very expensive to build; would not be worth it on a small scale in a remote place.

4) Fossil fuels generate electricity at a relatively low cost per kWh.

TEXTBOOK ANSWERS5) Hydroelectric schemes produce electricity

very efficiently.6) Wind turbines need replacing more often

than coal-fired power stations; many are needed to give a sizeable output; but even a large number of them are cheaper to build than a power station; wind is free.Coal-fired power stations produce large amounts of electricity per power station relatively cheaply for decades; but we must pay for the fuel;, and at the end of their life they are very expensive to replace.Wind turbines may be as cost-effective over a long timescale.

WORKSHEET ANSWERS

WORKSHEET ANSWERSActivity 2 (Standard demand) Situation 1: wind turbines; other possible options are

solar, waves, biofuel generator; reasons are that wind blows almost constantly; wind turbines can be easily installed in small areas; there is too little sunshine for high output from solar power; wave and biofuel generators are not well developed yet.

Situation 2: fossil fuel; other possible options are nuclear; wind, biofuel; reasons are that a large amount of electricity is needed, and transport links for fuel deliveries is good; the region is too heavily populated for nuclear power to be accepted as a safe option; the region is not hilly enough for reliable wind power; biofuel generators are not well developed.