3. Power stations What are the energy changes that occur? Cooling tower Turbine Generator Transformer Boiler

4. What does each part do? The boiler is where the fuel is burnt to boil water The steam from the boiler is used to turn a turbine The turbine is connected to the generator, which acts like a dynamo – it generates electricity out of movement The steam is cooled down and turned back into water in the cooling tower

5. Nuclear power stations These work in a similar way to normal power stations: The main difference is that the nuclear fuel is NOT burnt – it is used to boil water in a “heat exchanger”

6. Advantages of non-renewable fuels Relatively cheap Reliable Flexible in meeting demand Relatively easy to find Cheap fuel costs Don’t produce as much pollution Coal, oil and gas Nuclear

7. The problems… Power stations using coal, oil, gas or nuclear fuels can certainly whack out the energy, BUT… Problem 1 – Fossil fuels and nuclear sources will RUN OUT Problem 2 – Burning fossil fuels in oxygen will pollute the atmosphere Problem 3 - Nuclear plants run the risk of contamination and the cost of shutting them down (“decommissioning”) is very high So what’s the solution?

8. Other ways of generating electricity… Can we drive the turbine DIRECTLY?

9. Other ways of generating electricity… Wind Tidal Wave Hydro-electric

10. What are the disadvantages of these renewable forms of energy? Hydroelectric Tidal Wave Wind Disadvantages Source

11. Also, these sources all have high setting up costs Habitats can be destroyed, only good as a “short term” supply Hydroelectric Depends on size of tides, harms wildlife, visual pollution Tidal Harms wildlife, depends on size of waves, depends on weather Wave Depends on weather, visual pollution, difficult to “store” Wind Disadvantages Source

12. Summary Renewable sources of energy are cheaper, cleaner and will not run out. However, they are incapable of providing all the energy we need, so we will have to go on burning fossil fuels for now.