再生与不可再生能源（英文）课件

按一下以編輯母片標題樣式,按一下以編輯母片,第二層,第三層,第四層,第五層,*,单击此处编辑母版标题样式,单击此处编辑母版文本样式,第二级,第三级,第四级,第五级,*,Integrated Science Renewable and Nonrenewable energy sources,Integrated Science Renewable,1,Introduction of sources of energy,Non-Renewable,Fossil Fuels,Nuclear,Renewable,Wind,Solar,Tidal,Hydropower,5. Geothermal,Introduction of sources of ene,2,Non-Renewable energy sources:,1.Fossil Fuels,Non-Renewable energy sources:,3,What are fossil fuels ?,A fuel is,any substance used as a source of energy, including heating, transport, electricity generation and other uses.,Most of the worlds energy is provided by the burning of fossil fuels (,化石燃料,).,Coal, Oil and Gas,are called fossil fuels”because they are,natural combustible,substances,formed originally from dead plants and animals.,What are fossil fuels ?A fuel,4,再生与不可再生能源（英文）课件,5,The,major fossil fuels,are,coal,(,煤,),petroleum,(,石油,),and,natural gas,(,天然氣,).,Fossils fuels are,non-renewable (,非再生能源,),energy sources.,This is because fossil fuels take millions of years to form. Once they are used up they can,never be replaced,.,The major fossil fuels are Fos,6,World Fuel Resources,Petroleum or Oil,Natural Gas,Coal,Power reserves,130 billion tonnes,158 billion cubic metres,950 billion tonnes,Total used in 1990,2.2 billion tonnes,1.5billion cubic metres,2.2 billion tonnes,From the above table, the present worlds estimated,oil reserves,may be,used up in the next 50 to 60 years.,World Fuel Resources Petroleu,7,Coal,Coal is the,plants,that grew in swampy areas about 300 millions ago,died to form layers of decaying material.,Heat,pressure,and,the action of bacteria,changed the decaying plants into coal.,CoalCoal is the plants ,that g,8,再生与不可再生能源（英文）课件,9,How it works:,Coal is crushed to a fine dust and burnt.,How it works:,10,How is coal used?,Today, about 70 % of the total coal mined is burned in power station.,Coal Education (coaleducation.org/),How is coal used?Today, about,11,Petroleum,Petroleum,12,1.How was petroleum formed?,Petroleum was formed from,small sea animals,and,plants,that lived millions of years ago. After they died,heat,;,pressure,; and,the action of bacteria,changed the remains into oil. The oil formed was then trapped as small drops inside the pores of rocks.,Petroleum (petroleum.co.uk/),1.How was petroleum formed? P,13,再生与不可再生能源（英文）课件,14,How is petroleum used?,The thick crude oil that comes from the ground is a complex mixture of compounds. It is necessary to separate the compounds. The separated substances have two main uses:,as sources of useful fuels. e.g. petrol,as raw materials to make other products. e.g. plastics, detergents.,How is petroleum used? The thi,15,Products Made from a Barrel of Crude Oil,Products Made from a Barrel of,16,再生与不可再生能源（英文）课件,17,Natural Gas,Natural Gas,18,Natural gas is found together,with oil,and sometimes,with coal,.,The gas consists mainly of methane CH,4,.,Natural Gas (naturalgas.org/),Source : naturalgas.org,Natural gas is found together,19,In some countries, the gas is carried by pipes to homes and factories for heating and cooking.,In some countries, the gas is,20,HOW NATURAL GAS IS STORED AND DELIVERED,HOW NATURAL GAS IS STORED AND,21,How is petroleum used?,How is petroleum used?,22,The advantage and disadvantages of using fossil fuel,The advantage and disadvantage,23,Advantages,Very large amounts of electricity can be generated in one place using coal, fairly cheaply.,Transporting oil and gas to the power stations is easy.,Gas-fired power stations are very efficient.,A fossil-fuelled power station can be built almost anywhere,Advantages Very large amounts,24,Disadvantages,Pollution,Burning any fossil fuel produces carbon dioxide, which contributes to the greenhouse effect, warming the Earth.,Burning coal produces more carbon dioxide than burning oil or gas. It also produces sulphur dioxide, a gas that contributes to acid rain. We can reduce this before releasing the waste gases into the atmosphere. Mining coal can be difficult and dangerous.,Strip mining destroys large areas of the landscape.,Disadvantages Pollution Burn,25,Non-Renewable energy sources:2.Nuclear Energy,Non-Renewable energy sources:,26,What are Nuclear Power?,Nuclear power,is generated using,Uranium, which is a metal mined in various parts of the world.,Some military ships and submarines have nuclear power plants for engines.,Nuclear power produces around 11% of the worlds energy needs, and produces huge amounts of energy from small amounts of fuel, without the pollution that youd get from burning fossil fuels,What are Nuclear Power?Nuclea,27,How it works,Nuclear power stations work in pretty much the same way as fossil fuel-burning stations, except that a chain reaction inside a nuclear reactor makes the heat instead.,The reactor uses Uranium rods as fuel, and the heat is generated by,nuclear fission,. Neutrons smash into the nucleus of the uranium atoms, which split roughly in half and release energy in the form of heat.,Carbon dioxide gas is pumped through the reactor to take the heat away, and the hot gas then heats water to make steam.,The steam drives turbines which drive generators. Modern nuclear power stations use the same type of turbines and generators as conventional power stations.,How it works Nuclear power st,28,Advantages,Nuclear power costs about the same as coal, so its not expensive to make.,Does not produce smoke or carbon dioxide, so it does not contribute to the greenhouse effect.,Produces huge amounts of energy from small amounts of fuel.,Produces small amounts of waste.,AdvantagesNuclear power costs,29,Disadvantages,It is,very, very dangerous,.,It,must,be sealed up and buried for many years to allow the radioactivity to die away.,It is,reliable,but a lot of money has to be spent on safety - if it,does,go wrong, a nuclear accident can be a major disaster.,People are increasingly concerned about the safety.,DisadvantagesIt is very, very,30,Renewable energy sources:1.Wind,Renewable energy sources:1.W,31,Introduction,Weve used the,wind as an energy source,for a long time.,Wind power,was used in the Middle Ages, in Europe,to grind corn, which is where the term ,windmill, comes from.,Introduction Weve used the w,32,How it works,The wind blows the propellor round,which turns a generator to produce electricity.,How it works The wind blows t,33,The more towers, the more wind, and the larger the propellors, the more electricity we can make,.,Its only worth building wind farms in places that have strong, steady winds, although boats and caravans increasingly have small wind generators to help keep their batteries charged.,The more towers, the more wind,34,Advantages,Wind is free, wind farms need no fuel.,Produces,no waste,or,greenhouse gases.,The land beneath can usually still be used for farming.,Wind farms can be,tourist attractions.,A good method of supplying energy to remote areas.,Advantages Wind is free, wind,35,Disadvantages,The wind is,not always predictable,- some days have no wind.,Suitable areas for wind farms are often near the coast, where,land is expensive.,Some people feel that covering the landscape with these towers is,unsightly.,Can,kill birds,- migrating flocks tend to like strong winds.,Can affect,television reception,if you live nearby.,Can be,noisy.,Disadvantages The wind is not,36,Renewable energy sources:2.Solar Power,Renewable energy sources:2.S,37,Introduction,Weve used the Sun for drying clothes and food for thousands of years, but only recently have we been able to use it for generating power.,Just the tiny fraction of the Suns energy that hits the Earth (around a hundredth of a millionth of a percent) is enough to meet all our power needs many times over.,In fact, every minute, enough energy arrives at the Earth to meet our demands for a whole year - if only we could harness it properly.,Introduction Weve used the,38,How it works,There are two main ways that we use the Suns energy:-,Solar Cells-,that convert,light directly into electricity.,2.,Solar water heating,-where,heat from the Sun is used to,heat water in glass panels,on your roof.,How it works There are two ma,39,Advantages,Solar energy is free,- it needs no fuel,and produces no waste or pollution.,In sunny countries, solar power can be used where there is no easy way to get electricity to a remote place.,Handy for,low-power uses,such as solar powered garden lights and battery chargers,Advantages Solar energy is fre,40,Disadvantages,Doesnt work at night,.,Very expensive,to build solar power stations.Solar cells cost a great deal compared to the amount of electricity theyll produce in their lifetime.,Can be,unreliable,unless youre in a very sunny climate. In the United Kingdom, solar power isnt much use except for low-power applications, as you need a very large area of solar panels to get a decent amount of power.,Disadvantages Doesnt work at,41,Renewable energy sources:3.Tidal Power,Renewable energy sources:3.T,42,Introduction,The tide moves a huge amount of water twice each day, and harnessing it could provide a great deal of energy - around 20% of Britains needs.,Although the energy supply is reliable and plentiful, converting it into useful electrical power is not easy. There are eight main sites around Britain where tidal power stations could usefully be built, including the Severn, Dee, Solway and Humber estuaries.,Only around 20 sites in the world have been identified as possible tidal power stations.,IntroductionThe tide moves a,43,How it works: Tidal Barrages,These work rather like a,hydro-electric,scheme,except that the dam,is,much,bigger.,A huge dam,(called a barrage) is built,across a river estuary.,When the tide goes,in and out, the water,flows through tunnels,in the dam.,How it works: Tidal Barrages T,44,Advantages,Once youve built it,tidal power is free.,It produces,no greenhouse gases or other waste.,It needs,no fuel.,It produces,electricity reliably.,Not expensive,to maintain.,Tides are,totally predictable.,Advantages Once youve built i,45,Disadvantages,A barrage across an estuary is very expensive to build, and affects a very wide area - the environment is changed for many miles upstream and downstream. Many birds rely on the tide uncovering the mud flats so that they can feed. There are few suitable sites for tidal barrages.,Only provides power for around 10 hours each day, when the tide is actually moving in or out.,Disadvantages A barrage across,46,Renewable energy sources:4.Hydropower,Renewable energy sources:4.H,47,Introduction,We have used running water as an energy source for thousands of years, mainly to grind corn.,The first use of water to generate electricity was in 1882 on the Fox river, in the USA, which produced enough power to light two paper mills and a house.,Nowadays there are many hydro-electric power stations, providing around 20% of the worlds electricity. The name comes from hydro, the Greek word for water.,Introduction We have used run,48,How it works,A dam is built to trap water, usually in a valley where there is an existing lake.,Water is allowed to flow through tunnels in the dam, to turn turbines and thus drive generators.,Notice that the dam is much thicker at the bottom than at the top, because the pressure of the water increases with depth.,How it works A dam is built to,49,Advantages,Once the dam is built,the energy is virtually free.,No waste or pollution produced.,Much more reliable,than wind, solar or wave power.,Water can be stored,above the dam ready to cope with peaks in demand.,Hydro-electric power stations can,increase to full power,very quickly, unlike other power stations.,Electricity can be generated constantly.,Advantages Once the dam is bu,50,Disadvantages,The dams are very expensive to build.However, many dams are also used for flood control or irrigation, so building costs can be shared.,Building a large dam will flood a very large area upstream, causing problems for animals that used to live there.,Finding a suitable site can be difficult - the impact on residents and the environment may be unacceptable.,Water quality and quantity downstream can be affected, which can have an impact on plant life,Disadvantages The dams are ve,51,Renewable energy sources:5.Geothermal,Renewable energy sources:5.G,52,Introduction,The centre of the Earth is around 6000 degress Celsius - hot enough to melt rock. Even a few kilometres down, the temperature can be over 250 degrees Celsius.,In general, the temperature rises one degree Celsius for every 36 metres you go down.,In volcanic areas, molten rock can be very close to the surface.,Geothermal energy has been used for thousands of years in some countries for cooking and heating.,The name geothermal comes from two Greek words: geo means Earth and thermal means heat.,IntroductionThe centre of the,53,How it works,Hot rocks underground heat water to produce steam. We drill holes down to the hot region, steam comes up, is purified and used to drive turbines, which drive electric generators.,There may be natural groundwater in the hot rocks anyway, or we may need to drill more holes and pump water down to them.,How it works Hot rocks undergr,54,Advantages,Geothermal energy does not produce any pollution, and does not contribute to the greenhouse effect.,The power stations do not take up much room, so there is not much impact on the environment.,No fuel is needed.,Once youve built a geothermal power station, the energy is almost free. It may need a little energy to run a pump, but this can be taken from the energy being generated,Advantages Geothermal energy d,55,Disadvantages,The big problem is that there are not many places where you can build a geothermal power station. You need hot rocks of a suitable type, at a depth where we can drill down to them. The type of rock above is also important, it must be of a type that we can easily drill through.,Sometimes a geothermal site may run out of steam, perhaps for decades.,Hazardous gases and minerals may come up from underground, and can be difficult to safely dispose of.,Disadvantages The big problem,56,Conclusion,Though there are more and more renewable energy sources ,saving energy is very important.,ConclusionThough there are mo,57,xiexie!,谢谢！,xiexie!谢谢！,58,