Lesson 9: Renewable Energy Sources

 MUST understand that some renewable sources of energy drive a turbine directly  SHOULD understand that while technology can improve the quality of life, unintended impacts may be undesirable

 You need to be able to define the following:  Hydroelectric  Wind turbine  Wave technology  National Grid

1)Renewable energy resources will not run out. 2)Wind; hydroelectric; tidal; wave. 3)Benefit: renewable; can generate large amounts of electricity quickly. Problem: cause flooding; costly to build; dams must be maintained; greenhouse gases are emitted in the initial stages. 4)Large batteries could store surplus energy produced.

5)Only a small number of sites can generate useful amounts of energy from waves; the technology is still being developed. 6)Credit well thought-out answers with explanations. For example: a) Using wind turbines reduces greenhouse gas emissions, but the supply of electricity is expensive and unreliable. We need a reliable source of electricity, so the benefits of using only wind turbines do not outweigh the additional cost of the electricity generated, or the problems of unreliable supply. Wind turbines are probably best used to top up other forms of electricity generation. b) Using hydroelectric schemes reduces greenhouse gas emissions once established, but they are expensive to build and flood large areas; this is probably acceptable because the electricity is generated in large quantities and reliably.

Activity 2 (Standard demand)  Students’ reports should include points such as the following.  Solar energy: e.g. on satellites; produces energy directly; no pollution; can be used in remote areas; expensive per unit produced; no use at night.  Hydroelectricity: in mountainous regions; reliable source of large amounts of energy; floods large areas; dams need maintaining.  Wind power: in coastal and hilly areas; can be sited in many areas; no pollution; weather dependent; dilute energy source.  Wave energy: on coastline; no pollution; can be used in remote areas; only small amounts of energy produced; weather dependent; technology still being developed.  Tidal: in large estuaries; reliably produces large amounts of energy; only suitable in some areas; high cost of construction; effect on shipping and wildlife.

Activity 3 (High demand)  Points that could be included: larger offshore wind farms generate more electricity than onshore farms but there are problems transporting the electricity onshore; offshore wind farms are more expensive to construct and maintain, and the effects of the sea on the turbines means they may have a shorter lifespan; these factors will affect the cost of electricity for customers.