Page 165 - Science Coursebook
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11.2  Fossil fuels







                Generating electricity
                Electricity is a convenient way of sending
                energy from place to place. Most electricity is
                generated in power stations which burn fossil
                fuels, especially coal and gas.








                                                                       A coal fired power station in China.
                  Activity 11.2
                   nuclear fuel
                  Energy changes

                   A nuclear power station is supplied with nuclear fuel. It produces electricity.
                   Some energy is wasted – it escapes as heat energy.

                   The diagram shows the inputs and outputs with red arrows. The blue energy
                   arrow shows the energy change which takes place within the power station.



                                                                             heat energy






                            nuclear fuel                                             electricity




                                              nuclear energy         electrical energy


                   Your task is to draw similar diagrams for the situations described below. You
                   may need to revise the different forms that energy can take. Look at Stage 7
                   Unit 10 again.

                   1   Coal is burned in a power station to generate electricity.
                   2   When a car starts moving, it uses petrol stored in its fuel tank.
                   3   A stove uses gas to heat water for cooking.
                   4  An aircraft burns kerosene to fly fast and high.



                  Summary
                  •  Fossil fuels are stores of chemical energy.
                  •  Fossil fuels are burnt to release their energy.
                  •  Most of our electricity is generated in fossil fuel power stations.



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