Module P9 - Energy Aim - Electricity is a secondary energy source. This means that some other energy resources have to be used to make it. We (the human race) must carefully consider the advantages and disadvantages of using each energy source. This enables us to decide which it would be best to use. This activity helps you to explore the good and bad points about the main energy resources. Click the mouse when each slide is finished, in order to move to the next slide. Generating electrical energy

Coal, oil and gas are all fossil fuels. They release energy when they are burned. There is only a limited amount of these fuels. They are therefore called non-renewable energy resources. Uranium is a fuel used in some nuclear power stations. It is also a non- renewable energy resource.

It will take millions of years to replace the fossil fuels when they have been used up. Most energy used by humans comes from non renewable energy resources. The more economical that we are with these fossil fuels … … the longer they will last. Generating electrical energy

Trees can be cut down and used as fuel. More trees can be grown to replace these. Wood is therefore a renewable energy resource. Other renewable energy resources include: sunlight wind waves running water tides Generating electrical energy

Renewable energy resources will not run out. Electricity is a convenient energy resource. It is generated in power stations. Other energy resources are used. These resources are usually non renewable and … … pollute the air.

Fossil fuels are the most widely used for generating electricity. They contain a lot of carbon This reacts with oxygen in the air when the fuel is burnt … … forming carbon dioxide. Fossil fuels also contain some sulphur. This reacts with oxygen in the air when the fuel is burnt … … forming sulphur dioxide. Generating electrical energy

Carbon dioxide is a gas. This pollutes the atmosphere. Carbon dioxide is thought to contribute to global warming. Global warming is also called the greenhouse effect Sulphur dioxide is a gas. This pollutes the atmosphere. Sulphur dioxide contributes to acid rain. Generating electrical energy

Burning coal produces more carbon dioxide than oil or gas. Burning gas produces the lowest amount of carbon dioxide. There is no practical way to stop this gas getting into the atmosphere. Sulphur dioxide can be removed from the waste gases before it gets into the air. Sulphur can also be removed from the fuel so that sulphur dioxide is not formed. Doing these increases the cost of electricity. Generating electrical energy

Many power stations burn fossil fuels. Heat from burning the fuel is used to boil water. The steam from the boiling water is passed through a steam turbine. This causes the turbine to turn (kinetic energy). The turning turbine is used to turn a generator. The generator transfers the kinetic energy into electrical energy Generating electrical energy

Nuclear power stations use plutonium and uranium as fuel. These are not burnt. They give out heat (and radioactivity). The heat is used to boil water. The steam produced turns turbines and generators. When nuclear fuel is used up, it is more radioactive than it was at first. It has to be disposed of carefully. Generating electrical energy

Nuclear fuels do not release any polluting gases into the air. Nuclear power doesn’t contribute to acid rain or global warming. Unless there is an accident, radiation does not get out of a nuclear power station. Waste nuclear fuels stay radioactive for thousands of years. This makes it expensive and dangerous to handle and store after it has been used. Nuclear fuels are non renewable resources Generating electrical energy

Power stations that use fuels are reliable, they produce electricity at any time The time it takes to start them up varies. Longest... nuclear coal oil natural gas … to shortest Generating electrical energy

When deciding on which energy resource to use … … renewable and/or no-renewable... … the environmental and social aspects need to be considered The next slides give further information that can help you to make up your mind. Generating electrical energy

There are no fuel costs with renewable resources but the energy is much more dilute than with non-renewables. This makes the cost of the generating equipment high since you need a lot more than in conventional power stations. Generating electrical energy

The running costs of nuclear power stations are low. They are very expensive to build. They are very expensive to de-commission at the end of their useful lives. Processing and storage of the waste is expensive, dangerous and controversial.

Click on the picture below to launch the database about renewable energy resources Generating electrical energy