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Energy. Menu. Non- Renewable Energy Renewable Energy Wind Hydro-electric Biogas & Biomass Tidal Solar Geothermal Summary of Renewable s. Nuclear Energy AC and DC Transformers Power Stations National Grid. Non- Renewable Sources of Energy. Non- Renewable Energy.
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Menu • Non- Renewable Energy • Renewable Energy • Wind • Hydro-electric • Biogas & Biomass • Tidal • Solar • Geothermal • Summary of Renewables • Nuclear Energy • AC and DC • Transformers • Power Stations • National Grid
Non- Renewable Energy Coal, Oil & Natural Gas are called Fossil Fuels as they are made from the remains of animals & plants that lived millions of years ago. They are very concentrated sources of energy. Oil is an especially useful material as it is the raw material for plastics, petrol & diesel.
Advantages of Non- Renewable Energy sources (Coal, Oil, Natural Gas & Nuclear) • Reliable • Very concentrated sources of energy • Can be used flexibly to meet • fluctuating demand • Relatively cheap & easy to find
What are the problems with Non- Renewable Energy Resources? Supplies are limited. When the fuels burn, their waste gases pollute the atmosphere and cause acid rain. Another serious concern is the release of carbon dioxide that contributes to global warming Return to Menu
What are the disadvantages of these renewable forms of energy?
All sources all have high setting up costs – particularly Tidal & Hydroelectric
How do we get energy from the wind? This involves putting lots of windmills (wind turbines) up in exposed places like on the moors or coasts. Each wind turbine has its own generator to make electricity directly
You would need about 5000 wind turbines to make the same electricity as a coal fired power station. This would require a large land area. The view would be spoiled and power wouldn’t be produced when it wasn’t windy. Initial costs are high BUT there are no fuel costs and minimal running costs. No Pollution! Return to Menu
Water falling from a high level at a fast speed has a lot of energy If the moving water can be forced through turbines, the turbines can be moved to drive generators and make electricity
What is a pumped storage power station? Water is held in the higher dam and allowed to flow through turbines to make electricity when the ‘plug is pulled’. The water in the lower reservoir is pumped back up to be used again when necessary Return to Menu
Pigs & other animals make a lot of waste In the form of manure! What can be done with all of this pooh? Put it in a biogas digester and make methane gas that you can cook with!
What is a Biogas Digester Rotting animal & plant waste can give off methane gas. This is similar to natural gas and can be used as a fuel
Biomass Wood is an important fuel in many countries. When wood is burned, it releases energy that the tree once took in from the Sun
The trees that are planted are fast growing. Unlike burning fossil fuels, wood burning does not cause a problem with the Greenhouse Effect because any CO2 released in the burning of the wood was removed when the trees grew in the first place. Because the trees are grown as quickly as they are burnt they will never run out
The forest can also be used as a leisure facility before the wood is harvested. Return to Menu
What is Tidal Energy? The source of energy is the Gravity of the Sun and the Moon. As the Earth rotates the force of gravity causes the water to ‘bulge’ – this is the ‘tide’. Tides are reliable – they happen twice a day and we can even predict the height of each tide.
What is a water turbine? When the tide moves through the turbine it spins and generates ‘clean’ energy. The energy is reliable. The turbines produce electricity when the tides move both ‘IN’ and ‘OUT’
Tidal power To gain enough energy we would need lots of underwater turbines. This would affect the movement of shipping lanes
The second best place in the world to get tidal energy is in the Severn Estuary Return to Menu
What is a SOLAR FURNACE? The Sun’s thermal radiation energy is reflected (and focussed) towards a ‘boiler’. The water heats up & changes state to steam. The steam has a large amount of kinetic energy which turns a turbine. Electricity is then generated by a generator.
This is a solar power station using solar cells Solar energy is very clean and cheap (although initially they may be expensive to set up). It is a very reliable form of energy in sunny countries – BUT only in the daytime! Return to Menu
What is Geothermal Energy? This is Heat from Underground. It is only possible in some areas of the world where hot rocks lie quite near the surface. The source of much of the heat is the slow decay of various radioactive elements including Uranium
How do we make electricity from Geothermal Energy? Water Steam Water is pumped down and heated by the hot rocks where it turns to steam. The steam rises because it is less dense and turns a turbine, which drives a generator to make electricity Return to Menu
Complete the table on the next slide • For each source of energy give:- • A description of how it is used • 2 advantages • 2 disadvantages • Try not to say the same thing more than once!
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. Return to Menu
Nuclear Energy This is uranium. A small amount of fuel produces a vast amount of energy. It also produces lots of radioactive waste! In a reactor, nuclear reactions release energy from the nuclei of uranium atoms. This heats water to make steam for driving generators
The Splitting up of Atoms Is Called Nuclear Fission Nuclear power stations and nuclear submarines are both powered by nuclear reactors In a nuclear reactor,a controlled chain reaction takes place in which uranium atoms split up and release energy in the form of heat. This turns water to steam to drive a turbine & generate electricity
Nuclear Processes Release More Energy Than Chemical Processes When a nucleus splits it gives out a lot more energy than a chemical bond. This is why nuclear bombs release a lot more energy than other bombs
What is a power station? Power Stations are places where electrical energy is made. Electrical Energy is a convenient form of energy to use in our homes.
Fossil Fuel Power Stations can generate a lot of pollution In the form of carbon dioxide, sulphur dioxide and smoke
And whole forests It can damage leaves The sulphur dioxide can lead to the production of acid rain Return to menu
What is the National Grid? When electricity is generated in the power station it is transported to us by the National Grid It is a network of pylons and cables that covers the whole country
The National Grid Power Station 25,000V Step-down Transformer Homes Step-up Transformer 400,000V 230V Return to Menu
Alternating Current (AC) Voltage The current changes direction 50 times every second (frequency = 50Hz) Time AC is easier to generate than DC