1. Science A Physics – P1 Science A Physics – P1 Topic 1: Electricity Generation – 2a Topic 1: Electricity Generation – 2a

2.  A more economical and efficient use of fuels. Our attempts to conserve fuels and reduce pollution have resulted in the following strategies being employed:  Research into alternative energy sources.  The use of better materials to insulate buildings so that less energy is needed to heat them. Generating Electricity - Alternatives

3. Many environmental groups support the use of alternative sources of electricity generation such as:  Wind Energy Wind Energy  Wave Energy Wave Energy  Tidal Energy Tidal Energy  Hydroelectric Energy Hydroelectric Energy  Geothermal Energy Geothermal Energy  Solar Energy Solar Energy Most of these alternative sources have the advantage of being renewable energy sources and non-polluting. Generating Electricity - Alternatives  Energy Debate Energy Debate

4. Wind can be used to drive wind turbines which generate electricity. Numerous wind turbines are positioned in designated areas. Each has its own generator inside. As the wind blows, the blades turn the generator producing electricity. Wind Power

5. After initial set-up costs, no fuel is required and the running costs are minimal. Although large areas of land are required, much of the land in-between individual turbines is still available for agriculture or other purposes. Some people complain that wind turbines are noisy and spoil the landscape. Wind Power

6. How a Wind Turbine Works The wind turns the propeller blades, which drive the generator that produces the electricity. The housing turns to face the wind, to maximise the speed of the propeller blades.

7. As waves approach the shore, the water level rises and falls. This motion can be used directly to move a ‘duck’ system up and down, and convert this to rotational movement which is used to drive a turbine and thereby generate electricity. Wave Energy

8. An alternative method, currently used in Scandinavia and the UK, is to let the wave hit the shoreline and to funnel the wave surge up into a vertical air chamber. As the wave surge rises up the chamber it pushes air before it and this can be used to drive a turbine and a generator. Wave Energy

9. Set-up costs are relatively low when compared to fossil fuel/nuclear power stations. Maintenance costs are also relatively low. Wave power cannot produce large amounts of energy at present.

10. How a Wave Machine Works Use the animation to find out more about wave machines...

11. As tidal waters come in, they are held in an area behind a barrage, raising the water level by several metres. Electricity is generated as the water exits through turbines. Set-up costs are relatively low when compared to fossil fuel/nuclear power stations. Running costs are also relatively low. Tidal Energy Tidal Generating Station (Annapolis Royal, Nova Scotia, Canada) Tidal power restricts entry to the river for shipping and fish, and affects local habitats.

12. How Tidal Power Works Use the animation to find out more about tidal power...

13. Hydro-Electric Power Hydro-Electricity uses falling water from a reservoir to drive turbines and generate electricity. To create the reservoir a river has to be dammed. The water falls through giant tunnels or pipes and exits through turbines. The turbines drive generators which produce electricity.

14. All power stations require turbines to drive the generators. Generator Turbine The turbine hall of a hydro-electric power station.

15. The Hoover dam was finished in 1936 and originally cost $165,000,000 dollars - it is still producing electricity today! Hydro-Electric Power As with other alternative forms of electricity, production running costs are minimal. Large areas of land have to be flooded, and dams do restrict the flow of water, which changes habitats. However, the initial set-up costs are higher than some other alternative energy sources.

16. Turbines inside the Hoover dam Hydro-Electric Power

17. A turbine is basically a water wheel driven by water or steam. Hydro-Electric Power