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Fuel Cells: 21st Century Electricity The 21st century’s leading energy source may very well depend on the development of a technology that was first discovered in 1839. Indeed, many experts believe that the future of electricity generation will not come from further refinement of solar, wind, coal or nuclear energy, but from fuel cells. Among the various types of fuel cells, the ceramic or solid oxide fuel cell promises to achieve the greatest efficiency of conversion of fossil fuels such as gas and coal to electricity while producing only very low levels of pollutants. To this end, a consortium comprising five leading organizations has established Ceramic Fuels Ltd, initially to expand fuel cell research and development and secondly, to bring the technology to commercial application. Ceramic fuel cells are electrochemical devices that directly convert fuels such as gasified coal or natural gas into electricity without the limitation of the Carnot cycle (an ideal thermodynamic cycle in which heat is taken onto a working fluid at a constant upper temperature and rejected at a constant lower temperature). In many respects, fuel cells work like batteries. As long as they are constantly supplied with fuel and oxidant, fuel cells can continuously produce power, removing the need for recharging. Fuel cells offer several advantages over traditional thermal power plants. The major difference between these two power generators is that the chemical energy of the fuel cell is converted directly to electrical power without intermediate conversion first to heat. The efficiency of a coal-fired thermal plant is typically in the range of 30%-35%. In a combined cycle gas turbine system running on natural gas, the maximum efficiency is in the range 45%-50%. Many experts believe high temperature fuel cells could reach efficiencies of 80%-85%. Ceramic fuel cells thus offer a more efficient and less polluting alternative to current power generation technologies. By-products from fuel cells are high quality heat, carbon dioxide and steam. The temperature of the exhaust gases is well above 500℃, meaning that solid oxide fuel cells are very attractive for electricity and heat generation as, in addition to supplying electricity, the leftover amounts of heat created during the process could be used to produce heat for industries, provide hot water supplies or warm buildings. Fuel cell technology is not new. In fact, the principles of fuel cell operation were first reported by British scientist Sir William Grove in 1839. His prototype used dilute sulphuric acid and operated at room temperature. Ceramic fuel cells developed much later, with the first one operating at 1000°C in 1937. Ceramic fuel cells offer many advantages over other energy systems: ● they have the potential to produce electricity efficient from several fuel sources ● they can generate large amounts of electricity ● they are relatively quick to install Fuel cell research and development is extremely competitive worldwide, with the USA, Japan and some European countries leading the charge to commercialize this promising technology. For instance, a Dutch Belgian company has developed a fuel cell for a Volkswagen van and is also working on a larger unit to power a bus. Additionally, a German company is working on a fuel cell for the European space shuttle program and for submarines, while a Canadian company is evaluating a fuel cell to be used in small buses. Recent reports point to promising large international markets for ceramic fuel cells. Prospects for fuel cells in South East Asian markets appear good. Several countries, including Indonesia, Thailand and The Philippines are expected to demonstrate high rates of growth in demand for power an encouraging situation for those countries quick enough to develop and commercialize fuel cell technology. Energy is a vital component of a technology-based society and the growing need for electricity generation by the most efficient method will ensure a promising future for ceramic fuel cell technology. The Ceramic Fuel Cells Ltd initiative represents a major collaborative venture between public and private sectors. It is envisaged that this venture will go a long way towards achieving a greater efficiency of energy use worldwide. Do the following statements reflect the claims of the writer in the Reading Passage? YES if the statement reflects the claims of the writer NO if the statement contradicts the claims of the writer NOT GIVEN if it is impossible to say what the writer thinks about this Statements: 1．Sir William Grove was a physicist. 2．Future transport vehicles may be powered by fuel cells. 3．European companies were first in the race to develop fuel cell technology. 4．Some rapidly developing South East Asian countries will soon market fuel cells. 5．Cooperation between private companies and governments will encourage wider use of efficient energy sources.
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更多 “问答题Fuel Cells: 21st Century Electricity The 21st century’s leading energy source may very well depend on the development of a technology that was first discovered in 1839. Indeed, many experts believe that the future of electricity generation will not come from further refinement of solar, wind, coal or nuclear energy, but from fuel cells. Among the various types of fuel cells, the ceramic or solid oxide fuel cell promises to achieve the greatest efficiency of conversion of fossil fuels such as gas and coal to electricity while producing only very low levels of pollutants. To this end, a consortium comprising five leading organizations has established Ceramic Fuels Ltd, initially to expand fuel cell research and development and secondly, to bring the technology to commercial application. Ceramic fuel cells are electrochemical devices that directly convert fuels such as gasified coal or natural gas into electricity without the limitation of the Carnot cycle (an ideal thermodynamic cycle in which heat is taken onto a working fluid at a constant upper temperature and rejected at a constant lower temperature). In many respects, fuel cells work like batteries. As long as they are constantly supplied with fuel and oxidant, fuel cells can continuously produce power, removing the need for recharging. Fuel cells offer several advantages over traditional thermal power plants. The major difference between these two power generators is that the chemical energy of the fuel cell is converted directly to electrical power without intermediate conversion first to heat. The efficiency of a coal-fired thermal plant is typically in the range of 30%-35%. In a combined cycle gas turbine system running on natural gas, the maximum efficiency is in the range 45%-50%. Many experts believe high temperature fuel cells could reach efficiencies of 80%-85%. Ceramic fuel cells thus offer a more efficient and less polluting alternative to current power generation technologies. By-products from fuel cells are high quality heat, carbon dioxide and steam. The temperature of the exhaust gases is well above 500℃, meaning that solid oxide fuel cells are very attractive for electricity and heat generation as, in addition to supplying electricity, the leftover amounts of heat created during the process could be used to produce heat for industries, provide hot water supplies or warm buildings. Fuel cell technology is not new. In fact, the principles of fuel cell operation were first reported by British scientist Sir William Grove in 1839. His prototype used dilute sulphuric acid and operated at room temperature. Ceramic fuel cells developed much later, with the first one operating at 1000°C in 1937. Ceramic fuel cells offer many advantages over other energy systems: ● they have the potential to produce electricity efficient from several fuel sources ● they can generate large amounts of electricity ● they are relatively quick to install Fuel cell research and development is extremely competitive worldwide, with the USA, Japan and some European countries leading the charge to commercialize this promising technology. For instance, a Dutch Belgian company has developed a fuel cell for a Volkswagen van and is also working on a larger unit to power a bus. Additionally, a German company is working on a fuel cell for the European space shuttle program and for submarines, while a Canadian company is evaluating a fuel cell to be used in small buses. Recent reports point to promising large international markets for ceramic fuel cells. Prospects for fuel cells in South East Asian markets appear good. Several countries, including Indonesia, Thailand and The Philippines are expected to demonstrate high rates of growth in demand for power an encouraging situation for those countries quick enough to develop and commercialize fuel cell technology. Energy is a vital component of a technology-based society and the growing need for electricity generation by the most efficient method will ensure a promising future for ceramic fuel cell technology. The Ceramic Fuel Cells Ltd initiative represents a major collaborative venture between public and private sectors. It is envisaged that this venture will go a long way towards achieving a greater efficiency of energy use worldwide. Do the following statements reflect the claims of the writer in the Reading Passage? YES if the statement reflects the claims of the writer NO if the statement contradicts the claims of the writer NOT GIVEN if it is impossible to say what the writer thinks about this Statements: 1．Sir William Grove was a physicist. 2．Future transport vehicles may be powered by fuel cells. 3．European companies were first in the race to develop fuel cell technology. 4．Some rapidly developing South East Asian countries will soon market fuel cells. 5．Cooperation between private companies and governments will encourage wider use of efficient energy sources.” 相关考题
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By the middle of the 21st century，the vast majority of the world‘s population will be living in cities _______ in the country. A. other than B. more than C. better than D. rather than
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第一篇Renewable Energy SourcesToday petroleum（石油）provides around 40% of the world's energy needs, mostly fuelling automobiles.Coal is still used,mostly in power stations,to cover one-quarter of our energy needs,but it is the least efficient,unhealthiest and most environmentally damaging fossil fuel（矿物燃料）.Natural gas reserves could fill some of the gap from oil,but reserves of that will not last into the 22nd century either. Most experts predict we will exhaust easily accessible reserves within 50 years.Less-polluting renewable energy sources offer a more practical long-term energy solution."Renewable"refers to the fact that these resources are not used faster than they can be replaced.Hydroelectric（水力发电的）power is now the most common form of renewable energy,suDDIvina around 20%of world electricity.China's Three Gorges Dam is the largest ever. At five times the size of the US's Hoover Dam, its 26 turbines（涡轮机）will generate the equivalent energy of 18 coal-fired power stations.It will satisfy 3% of China's entireelectricity demand.In 2003. the first commercial power station to use tidal（潮汐的）currents in the open sea opened in Norway. It is designed like windmill（风车）,but others take the torm ofturbines.As prices fall,wind power has become the fastest growing type of electricity generation一quadrupling（翻两番）worldwide between 1999 and 2005. Modern wind farms consist of turbines that generate electricity.Though it will be more expensive,there is more than enoucih wind to provide the world's entire energy needs.Wind farms come in onshore and offshore forms.They can often end up at spots of natural beauty,and are often unpopular with residents.And turbines are not totally harmless一they can interfere with radar, alter climate and kill sea birds.Scotland is building Europe's largest wind tarm,wnicn will power 200.000 homes.The UK's goal is to generate one-fifth of power from renewable sources,mainly wind,by 2020.But this may cause problems,because wind is unreiiable.According to the passage,resources like wind areA:renewable. B:recyclable.C:damaging. D:scarce.
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第一篇Renewable Energy SourcesToday petroleum（石油）provides around 40% of the world's energy needs, mostly fuelling automobiles.Coal is still used,mostly in power stations,to cover one-quarter of our energy needs,but it is the least efficient,unhealthiest and most environmentally damaging fossil fuel（矿物燃料）.Natural gas reserves could fill some of the gap from oil,but reserves of that will not last into the 22nd century either. Most experts predict we will exhaust easily accessible reserves within 50 years.Less-polluting renewable energy sources offer a more practical long-term energy solution."Renewable"refers to the fact that these resources are not used faster than they can be replaced.Hydroelectric（水力发电的）power is now the most common form of renewable energy,suDDIvina around 20%of world electricity.China's Three Gorges Dam is the largest ever. At five times the size of the US's Hoover Dam, its 26 turbines（涡轮机）will generate the equivalent energy of 18 coal-fired power stations.It will satisfy 3% of China's entireelectricity demand.In 2003. the first commercial power station to use tidal（潮汐的）currents in the open sea opened in Norway. It is designed like windmill（风车）,but others take the torm ofturbines.As prices fall,wind power has become the fastest growing type of electricity generation一quadrupling（翻两番）worldwide between 1999 and 2005. Modern wind farms consist of turbines that generate electricity.Though it will be more expensive,there is more than enoucih wind to provide the world's entire energy needs.Wind farms come in onshore and offshore forms.They can often end up at spots of natural beauty,and are often unpopular with residents.And turbines are not totally harmless一they can interfere with radar, alter climate and kill sea birds.Scotland is building Europe's largest wind tarm,wnicn will power 200.000 homes.The UK's goal is to generate one-fifth of power from renewable sources,mainly wind,by 2020.But this may cause problems,because wind is unreiiable.China's Three Gorges DamA:is the first hydroelectric dam in the world.B:is of the same size as the US's Hoover Dam.C:can generate around 3%of world electricity.D:is the lamest hydroelectric dam in the world.
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第一篇Renewable Energy SourcesToday petroleum（石油）provides around 40% of the world's energy needs, mostly fuelling automobiles.Coal is still used,mostly in power stations,to cover one-quarter of our energy needs,but it is the least efficient,unhealthiest and most environmentally damaging fossil fuel（矿物燃料）.Natural gas reserves could fill some of the gap from oil,but reserves of that will not last into the 22nd century either. Most experts predict we will exhaust easily accessible reserves within 50 years.Less-polluting renewable energy sources offer a more practical long-term energy solution."Renewable"refers to the fact that these resources are not used faster than they can be replaced.Hydroelectric（水力发电的）power is now the most common form of renewable energy,suDDIvina around 20%of world electricity.China's Three Gorges Dam is the largest ever. At five times the size of the US's Hoover Dam, its 26 turbines（涡轮机）will generate the equivalent energy of 18 coal-fired power stations.It will satisfy 3% of China's entireelectricity demand.In 2003. the first commercial power station to use tidal（潮汐的）currents in the open sea opened in Norway. It is designed like windmill（风车）,but others take the torm ofturbines.As prices fall,wind power has become the fastest growing type of electricity generation一quadrupling（翻两番）worldwide between 1999 and 2005. Modern wind farms consist of turbines that generate electricity.Though it will be more expensive,there is more than enoucih wind to provide the world's entire energy needs.Wind farms come in onshore and offshore forms.They can often end up at spots of natural beauty,and are often unpopular with residents.And turbines are not totally harmless一they can interfere with radar, alter climate and kill sea birds.Scotland is building Europe's largest wind tarm,wnicn will power 200.000 homes.The UK's goal is to generate one-fifth of power from renewable sources,mainly wind,by 2020.But this may cause problems,because wind is unreiiable.According to the passage,which of the following is the most polluting energy resource?A:Petroleum. B:Coal.C:Natural gas. D:Water.
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Renewable Energy SourcesToday petroleum provides around 40%of the world's energy needs,mostly fuelling automobiles .Coal is still used,mostly in power stations,to cover one-quarter of our energy needs,but it is the least efficient,unhealthiest and most environmentally damaging fossil fuel.Natural gas reserves could plug some of the gap from oil,but reserves of that will not last into the 22nd century either.Most experts predict we will exhaust easily accessible reserves within 50 years.We could fasi reach an energy crisis.We need to rapidly develop sustainable solutions to fuel our future.Lesspolluting renewable energy sources offer a more practical long-term energy solution.They may benefit the world's poor too."Renewable"refers to the fact that these resources are not used faster than they can be replaced.The Chinese and Romans used watermills over 2,000 years ago. But the first hydroelectric dam was built in England in 1870.Hydroelectric power is now the most common form of renewable energy,supplying around 20%of world electricity. China's Three Gorges Dam,which has just been completed,is the largest ever. At five times the size of the US's Hoover Dam,its 26 turbines will generate the equivalent energy of 1 8 coal-fired power stations.It will satisfy 3%of China's entire electricity demand.Surprisingly,some argue that hydroelectric dams significantly contribute green- house gases.In 2003,the first commercial power station to harness tidal currents in the open sea opened in Norway .It is designed like windmill,but others take the form of turbines.As prices fall,wind power has become the fastest growing type of electricity generation-quadrupling worldwide between 1999 and 2005 .Modern wind farms consist of turbines that gener- ate electricity.Though it will be more expensive,there is more than enough wind to provide the world's entire energy needs. Wind farms come in onshore and offshore forms.They can often end up at spots of natural beauty,and are often unpopular with residents.And turbines are not totally benignthey can interfere with radar and leave a significant ecological footprint,altering climate and killing sea birds.Migrating birds may have more luck avoiding them.Scotland is buildingEurope's largest wind farm,which will power 200,000 homes.The UK's goal is to generate one- fifth of power from renewable sources,mainly wind,by 2020 .But this may cause problems,be- cause wind is unreliable. What are the energy resources that are renewable according to the article?A: Petroleum and coal.B: Natural gas.C: Wind and water.D: A and B.
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Renewable Energy SourcesToday petroleum provides around 40%of the world's energy needs,mostly fuelling automobiles .Coal is still used,mostly in power stations,to cover one-quarter of our energy needs,but it is the least efficient,unhealthiest and most environmentally damaging fossil fuel.Natural gas reserves could plug some of the gap from oil,but reserves of that will not last into the 22nd century either.Most experts predict we will exhaust easily accessible reserves within 50 years.We could fasi reach an energy crisis.We need to rapidly develop sustainable solutions to fuel our future.Lesspolluting renewable energy sources offer a more practical long-term energy solution.They may benefit the world's poor too."Renewable"refers to the fact that these resources are not used faster than they can be replaced.The Chinese and Romans used watermills over 2,000 years ago. But the first hydroelectric dam was built in England in 1870.Hydroelectric power is now the most common form of renewable energy,supplying around 20%of world electricity. China's Three Gorges Dam,which has just been completed,is the largest ever. At five times the size of the US's Hoover Dam,its 26 turbines will generate the equivalent energy of 1 8 coal-fired power stations.It will satisfy 3%of China's entire electricity demand.Surprisingly,some argue that hydroelectric dams significantly contribute green- house gases.In 2003,the first commercial power station to harness tidal currents in the open sea opened in Norway .It is designed like windmill,but others take the form of turbines.As prices fall,wind power has become the fastest growing type of electricity generation-quadrupling worldwide between 1999 and 2005 .Modern wind farms consist of turbines that gener- ate electricity.Though it will be more expensive,there is more than enough wind to provide the world's entire energy needs. Wind farms come in onshore and offshore forms.They can often end up at spots of natural beauty,and are often unpopular with residents.And turbines are not totally benignthey can interfere with radar and leave a significant ecological footprint,altering climate and killing sea birds.Migrating birds may have more luck avoiding them.Scotland is buildingEurope's largest wind farm,which will power 200,000 homes.The UK's goal is to generate one- fifth of power from renewable sources,mainly wind,by 2020 .But this may cause problems,be- cause wind is unreliable. Which of the following statements is true of wind power?A: There is plenty of wind to provide the world's entire energy needs.B: It is the most rapidly growing type of electricity production.C: It may not he reliable.D: All of the above.
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Renewable Energy SourcesToday petroleum provides around 40%of the world's energy needs,mostly fuelling automobiles.Coal is still used,mostly in power stations,to cover one-quarter of our energy needs,but it is the least efficient, unhealthiest and most environmentally damaging fossil fuel.Natural gas reserves could plug（填补）some of the gap from oil,but reserves of that will not last into the 22nd century either.Most experts predict we will exhaust easily accessible reserves within 50 years.We could fast reach an energy crisis.We need to rapidly develop sustainable solutions to fuel our future.Less-polluting renewable energy sources offer a more practical long-term energy solution.They may benefit the world's poor too."Renewable"refers to the fact that these resources are not used faster than they can be replaced.The Chinese and Romans used watermills over 2,000 years ago.But the first hydroelectric dam was built in England in 1870.Hydroelectric power is now the most common form of renewable energy,supplying around 20%of world electricity.China's Three Gorges Dam,which has just been completed, is the largest ever.At five times the size of the US ' s Hoover Dam , its 26 turbines（涡轮机）will generate the equivalent energy of 18 coal-fired power stations.It will satisfy 3%of China's entire electricity demand.In 2003,the first commercial power station to harness tidal currents in the open sea opened in Norway. It is designed like windmill,but others take the form of turbines.As prices fall,wind power has become the fastest growing type of electricity generation-quadrupling worldwide between 1999 and 2005.Modern wind farms consist of turbines that generate electricity.Though it will be more expensive,there is more than enough wind to provide the world's entire energy needs.Wind farms come in onshore and offshore forms.They can often end up at spots of natural beauty,and are often unpopular with residents.And turbines are not totally benign-they can interfere with radar and leave a significant ecological footprint,altering climate and killing sea birds.Migrating birds may have more luck avoiding them.Scotland is building Europe's largest wind farm,which will power 200 ,000 homes.The UK's goal is to generate one-fifth of power from renewable sources,mainly wind,by 2020.But this may cause problems,because wind is unreliable.Which is the country with the first commercial power station that makes use of ocean currents produced by tides?A:China. B:Norway.C:England. D:America.
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Renewable Energy SourcesToday petroleum provides around 40%of the world's energy needs,mostly fuelling automobiles .Coal is still used,mostly in power stations,to cover one-quarter of our energy needs,but it is the least efficient,unhealthiest and most environmentally damaging fossil fuel.Natural gas reserves could plug some of the gap from oil,but reserves of that will not last into the 22nd century either.Most experts predict we will exhaust easily accessible reserves within 50 years.We could fasi reach an energy crisis.We need to rapidly develop sustainable solutions to fuel our future.Lesspolluting renewable energy sources offer a more practical long-term energy solution.They may benefit the world's poor too."Renewable"refers to the fact that these resources are not used faster than they can be replaced.The Chinese and Romans used watermills over 2,000 years ago. But the first hydroelectric dam was built in England in 1870.Hydroelectric power is now the most common form of renewable energy,supplying around 20%of world electricity. China's Three Gorges Dam,which has just been completed,is the largest ever. At five times the size of the US's Hoover Dam,its 26 turbines will generate the equivalent energy of 1 8 coal-fired power stations.It will satisfy 3%of China's entire electricity demand.Surprisingly,some argue that hydroelectric dams significantly contribute green- house gases.In 2003,the first commercial power station to harness tidal currents in the open sea opened in Norway .It is designed like windmill,but others take the form of turbines.As prices fall,wind power has become the fastest growing type of electricity generation-quadrupling worldwide between 1999 and 2005 .Modern wind farms consist of turbines that gener- ate electricity.Though it will be more expensive,there is more than enough wind to provide the world's entire energy needs. Wind farms come in onshore and offshore forms.They can often end up at spots of natural beauty,and are often unpopular with residents.And turbines are not totally benignthey can interfere with radar and leave a significant ecological footprint,altering climate and killing sea birds.Migrating birds may have more luck avoiding them.Scotland is buildingEurope's largest wind farm,which will power 200,000 homes.The UK's goal is to generate one- fifth of power from renewable sources,mainly wind,by 2020 .But this may cause problems,be- cause wind is unreliable. According to the article,resources such as wind______.A: are sustainable hut not replaceableB: are renewable so sustainableC: are sustainable so renewableD: are irreplaceable
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Renewable Energy SourcesToday petroleum provides around 40%of the world's energy needs,mostly fuelling automobiles.Coal is still used,mostly in power stations,to cover one-quarter of our energy needs,but it is the least efficient, unhealthiest and most environmentally damaging fossil fuel.Natural gas reserves could plug（填补）some of the gap from oil,but reserves of that will not last into the 22nd century either.Most experts predict we will exhaust easily accessible reserves within 50 years.We could fast reach an energy crisis.We need to rapidly develop sustainable solutions to fuel our future.Less-polluting renewable energy sources offer a more practical long-term energy solution.They may benefit the world's poor too."Renewable"refers to the fact that these resources are not used faster than they can be replaced.The Chinese and Romans used watermills over 2,000 years ago.But the first hydroelectric dam was built in England in 1870.Hydroelectric power is now the most common form of renewable energy,supplying around 20%of world electricity.China's Three Gorges Dam,which has just been completed, is the largest ever.At five times the size of the US ' s Hoover Dam , its 26 turbines（涡轮机）will generate the equivalent energy of 18 coal-fired power stations.It will satisfy 3%of China's entire electricity demand.In 2003,the first commercial power station to harness tidal currents in the open sea opened in Norway. It is designed like windmill,but others take the form of turbines.As prices fall,wind power has become the fastest growing type of electricity generation-quadrupling worldwide between 1999 and 2005.Modern wind farms consist of turbines that generate electricity.Though it will be more expensive,there is more than enough wind to provide the world's entire energy needs.Wind farms come in onshore and offshore forms.They can often end up at spots of natural beauty,and are often unpopular with residents.And turbines are not totally benign-they can interfere with radar and leave a significant ecological footprint,altering climate and killing sea birds.Migrating birds may have more luck avoiding them.Scotland is building Europe's largest wind farm,which will power 200 ,000 homes.The UK's goal is to generate one-fifth of power from renewable sources,mainly wind,by 2020.But this may cause problems,because wind is unreliable.China's Three Gorges Dam ______.A:is the first hydroelectric dam in the worldB:is of the same size of the US's Hoover DamC:is the largest of all the hydroelectric dams in the worldD:supplies around 20%of the world electricity
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第一篇Renewable Energy SourcesToday petroleum provides around 40%of the world's energy needs,mostly fuelling automobiles.Coal is still used,mostly in power stations,to cover one-quarter of our energy needs,but it is the least efficient,un- healthiest and most environmentally damaging fossil fuel.Natural gas reserves could plug some of the gap from oil,but reserves of that will not last into the 22nd century either. Most experts predict we will exhaust easily accessible reserves within 50 years.We could fast reach an energy crisis.We need to rapidly develop sustainable solutions to fuel our future.Less-polluting renewable energy sources offer a more practical long-term energy solution. They may benefit the world's poor too."Renewable"refers to the fact that these resources are not used faster than they can be replaced.The Chinese and Romans used waterinills over 2, 000 years ago.But the first hydroelectric dam was built in England in 1870.Hydroelectric power is now the most common form of renewable energy,supplying around 20%of world electricity.China's Three Gorges Dam,which has just been completed,is the largest ever. At five times the size of the US's Hoover Dam,its 26 turbines will generate the equivalent energy of 18 coal- fired power stations.It will satisfy 3%of China's entire electricity demand.Surprisingly,some argue that hy- droelectric dams significantly contribute greenhouse gases.In 2003,the first commercial power station to harness tidal currents in the open sea opened in Norway. It is designed like windmill,but others take the form of turbines.As prices fall,wind power has become the fastest growing type of electricity generation一quadrupling worldwide between 1999 and 2005.Modern wind farms consist of turbines that generate electricity.Though it will be more expensive,there is more than enough wind to provide the world's entire energy needs. Wind farms come in onshore and offshore forms.They can often end up at spots of natural beauty,and are often un- popular with residents.And turbines are not totally benign一they can interfere with radar and leave a signifi- cant ecological footprint,altering climate and killing sea birds.Migrating birds may have more luck avoiding them.Scotland is building Europe's largest wind farms,which will power 200,000 homes.The UK's goal isto generate one-fifth of power from renewable sources,mainly wind,by 2020.But this may cause problems, because wind is unreliable.Which is the country with the first commercial power station that makes use of ocean currents produced by tides?A:China.B:Norway.C:England.D:America.
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第一篇Renewable Energy SourcesToday petroleum provides around 40%of the world's energy needs,mostly fuelling automobiles.Coal is still used,mostly in power stations,to cover one-quarter of our energy needs,but it is the least efficient,un- healthiest and most environmentally damaging fossil fuel.Natural gas reserves could plug some of the gap from oil,but reserves of that will not last into the 22nd century either. Most experts predict we will exhaust easily accessible reserves within 50 years.We could fast reach an energy crisis.We need to rapidly develop sustainable solutions to fuel our future.Less-polluting renewable energy sources offer a more practical long-term energy solution. They may benefit the world's poor too."Renewable"refers to the fact that these resources are not used faster than they can be replaced.The Chinese and Romans used waterinills over 2, 000 years ago.But the first hydroelectric dam was built in England in 1870.Hydroelectric power is now the most common form of renewable energy,supplying around 20%of world electricity.China's Three Gorges Dam,which has just been completed,is the largest ever. At five times the size of the US's Hoover Dam,its 26 turbines will generate the equivalent energy of 18 coal- fired power stations.It will satisfy 3%of China's entire electricity demand.Surprisingly,some argue that hy- droelectric dams significantly contribute greenhouse gases.In 2003,the first commercial power station to harness tidal currents in the open sea opened in Norway. It is designed like windmill,but others take the form of turbines.As prices fall,wind power has become the fastest growing type of electricity generation一quadrupling worldwide between 1999 and 2005.Modern wind farms consist of turbines that generate electricity.Though it will be more expensive,there is more than enough wind to provide the world's entire energy needs. Wind farms come in onshore and offshore forms.They can often end up at spots of natural beauty,and are often un- popular with residents.And turbines are not totally benign一they can interfere with radar and leave a signifi- cant ecological footprint,altering climate and killing sea birds.Migrating birds may have more luck avoiding them.Scotland is building Europe's largest wind farms,which will power 200,000 homes.The UK's goal isto generate one-fifth of power from renewable sources,mainly wind,by 2020.But this may cause problems, because wind is unreliable.China'S Three Gorges Dam_________.A:is the first hydroelectric dam in the worldB:is of the same size of the US's Hoover DamC:is the largest of all the hydroelectric dams in the worldD:supplies around 20%of the world electricity
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第一篇Renewable Energy SourcesToday petroleum provides around 40%of the world's energy needs,mostly fuelling automobiles.Coal is still used,mostly in power stations,to cover one-quarter of our energy needs,but it is the least efficient,un- healthiest and most environmentally damaging fossil fuel.Natural gas reserves could plug some of the gap from oil,but reserves of that will not last into the 22nd century either. Most experts predict we will exhaust easily accessible reserves within 50 years.We could fast reach an energy crisis.We need to rapidly develop sustainable solutions to fuel our future.Less-polluting renewable energy sources offer a more practical long-term energy solution. They may benefit the world's poor too."Renewable"refers to the fact that these resources are not used faster than they can be replaced.The Chinese and Romans used waterinills over 2, 000 years ago.But the first hydroelectric dam was built in England in 1870.Hydroelectric power is now the most common form of renewable energy,supplying around 20%of world electricity.China's Three Gorges Dam,which has just been completed,is the largest ever. At five times the size of the US's Hoover Dam,its 26 turbines will generate the equivalent energy of 18 coal- fired power stations.It will satisfy 3%of China's entire electricity demand.Surprisingly,some argue that hy- droelectric dams significantly contribute greenhouse gases.In 2003,the first commercial power station to harness tidal currents in the open sea opened in Norway. It is designed like windmill,but others take the form of turbines.As prices fall,wind power has become the fastest growing type of electricity generation一quadrupling worldwide between 1999 and 2005.Modern wind farms consist of turbines that generate electricity.Though it will be more expensive,there is more than enough wind to provide the world's entire energy needs. Wind farms come in onshore and offshore forms.They can often end up at spots of natural beauty,and are often un- popular with residents.And turbines are not totally benign一they can interfere with radar and leave a signifi- cant ecological footprint,altering climate and killing sea birds.Migrating birds may have more luck avoiding them.Scotland is building Europe's largest wind farms,which will power 200,000 homes.The UK's goal isto generate one-fifth of power from renewable sources,mainly wind,by 2020.But this may cause problems, because wind is unreliable.Which of the following statements is true of wind power?A:Here is plenty of wind to provide the world'S entire energy needs.B:It is the most rapidly growing type of electricity production.C:It may not be reliable.D:All of the above.
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第三篇Renewable Energy SourcesToday petroleum（石油）provides around 40% of the world's energy needs , mostly fuelling automobiles.Coal is still used,mostly in power stations,to cover one一quarter of our energy needs,but it is the least efficient,unhealthiest and most environmentally damaging fossil fuel（矿物燃料）.Natural gas reserves could fill some of the gap from oil, but reserves of that will not last into the 22nd century either. Most experts predict we will exhaust easily accessible reserves within 50 years.Less-polluting renewable energy sources offer a more practical long-term energy solution. "Renewable"refers to the fact that these resources are not used faster than they can be replaced.Hydroelectric（水力发电的）power is now the most common form of renewable energy, supplying around 20%of world electricity.China's Three Gorges Dam is the largest ever. At five times the size of the US's Hoover Dam , its 26 turbines（涡轮机）will generate theequivalent energy of 18 coal-fired power stations.It will satisfy 3% of China's entire electricity demand.In 2003, the first commercial power station to use tidal（潮汐的）currents in the open sea opened in Norway. It is designed like windmill（风车）,but others take the form of turbines.As prices fall,wind power has become the fastest growing type of electricity generation一 quadrupling（翻两番）worldwide between 1999 and 2005. Modern wind farms consist of turbines that generate electricity.Though it will be more expensive,there is more than enough wind to provide the world's entire energy needs.Wind farms come in onshore and offshore forms.They can often end up at spots of natural beauty,and are often unpopular with residents.And turbines are not totally harmless一they can intertere with radar,alter climate and kill sea birds.Scotland is building Europe's largest wind farm,which will power 200,000 homes.The UK's goal is to generate one-fifth of power from renewable sources, mainly wind,by 2020.But this may cause problems,because wind is unreliable.China's Three Gorges DamA:is the first hydroelectric dam in the world.B:is of the same size as the US's Hoover Dam.C:can generate around 3%of world electricity.D:is the largest hydroelectric dam in the world.
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共用题干
第三篇Renewable Energy SourcesToday petroleum（石油）provides around 40% of the world's energy needs , mostly fuelling automobiles.Coal is still used,mostly in power stations,to cover one一quarter of our energy needs,but it is the least efficient,unhealthiest and most environmentally damaging fossil fuel（矿物燃料）.Natural gas reserves could fill some of the gap from oil, but reserves of that will not last into the 22nd century either. Most experts predict we will exhaust easily accessible reserves within 50 years.Less-polluting renewable energy sources offer a more practical long-term energy solution. "Renewable"refers to the fact that these resources are not used faster than they can be replaced.Hydroelectric（水力发电的）power is now the most common form of renewable energy, supplying around 20%of world electricity.China's Three Gorges Dam is the largest ever. At five times the size of the US's Hoover Dam , its 26 turbines（涡轮机）will generate theequivalent energy of 18 coal-fired power stations.It will satisfy 3% of China's entire electricity demand.In 2003, the first commercial power station to use tidal（潮汐的）currents in the open sea opened in Norway. It is designed like windmill（风车）,but others take the form of turbines.As prices fall,wind power has become the fastest growing type of electricity generation一 quadrupling（翻两番）worldwide between 1999 and 2005. Modern wind farms consist of turbines that generate electricity.Though it will be more expensive,there is more than enough wind to provide the world's entire energy needs.Wind farms come in onshore and offshore forms.They can often end up at spots of natural beauty,and are often unpopular with residents.And turbines are not totally harmless一they can intertere with radar,alter climate and kill sea birds.Scotland is building Europe's largest wind farm,which will power 200,000 homes.The UK's goal is to generate one-fifth of power from renewable sources, mainly wind,by 2020.But this may cause problems,because wind is unreliable.According to the passage,resources like wind areA:renewable. B:recyclable.C:damaging. D:scarce.
考题
共用题干
Renewable Energy SourcesToday petroleum（石油）provides around 40% of the world's energy needs, mostly fuelling automobiles .Coal is still used,mostly in power stations,to cover one-quarter of our energy needs, but it is the least efficient, unhealthiest and most environmentally damaging fossil fuel（矿物燃料）.Natural gas reserves could fill some of the gap from oil,but reserves of that will not last into the 22nd century either. Most experts predict we will exhaust easily accessible reserves within 50 years. Less-polluting renewable energy sources offer a more practical long-term energy solution. "Renewable"refers to the fact that these resources are not used faster than they can be replaced.Hydroelectric（水力发电的）power is now the most common form of renewable energy , supplying around 20% of world electricity.China's Three Gorges Dam is the largest ever. At five times the size of the U. S. 's Hoover Dam,its 26 turbines (涡轮机）will generate the equivalent energy of 18 coal-fired power stations. It will satisfy 3%of China's entire electricity demand.In 2003,the first commercial power station to use tidal（潮汐的）currents in the open sea opened in Norway. It is designed like windmill（风车）,but others take the form of turbines.As prices fall,wind power has become the fastest growing type of electricity generation-quadrupling（翻两番）worldwide between 1 999 and 2005 . Modern wind farms consist of turbines that generate electricity. Though it will be more expensive,there is more than enough wind to provide the world's entire energy needs.Wind farms come in onshore and offshore forms. They can often end up at spots of natural beauty,and are often unpopular with residents. And turbines are not totally harmless-they can interfere with radar,alter climate and kill sea birds.Scotland is building Europe's largest wind farm,which will power 200 ,000 homes. The U.K. 's goal is to generate one-fifth of power from renewable sources,mainly wind,by 2020 .But this may cause problems, because wind is unreliable. According to the passage,resources like wind are______.A: renewableB: recyclableC: damagingD: scarce
考题
共用题干
Renewable Energy SourcesToday petroleum（石油）provides around 40% of the world's energy needs, mostly fuelling automobiles .Coal is still used,mostly in power stations,to cover one-quarter of our energy needs, but it is the least efficient, unhealthiest and most environmentally damaging fossil fuel（矿物燃料）.Natural gas reserves could fill some of the gap from oil,but reserves of that will not last into the 22nd century either. Most experts predict we will exhaust easily accessible reserves within 50 years. Less-polluting renewable energy sources offer a more practical long-term energy solution. "Renewable"refers to the fact that these resources are not used faster than they can be replaced.Hydroelectric（水力发电的）power is now the most common form of renewable energy , supplying around 20% of world electricity.China's Three Gorges Dam is the largest ever. At five times the size of the U. S. 's Hoover Dam,its 26 turbines (涡轮机）will generate the equivalent energy of 18 coal-fired power stations. It will satisfy 3%of China's entire electricity demand.In 2003,the first commercial power station to use tidal（潮汐的）currents in the open sea opened in Norway. It is designed like windmill（风车）,but others take the form of turbines.As prices fall,wind power has become the fastest growing type of electricity generation-quadrupling（翻两番）worldwide between 1 999 and 2005 . Modern wind farms consist of turbines that generate electricity. Though it will be more expensive,there is more than enough wind to provide the world's entire energy needs.Wind farms come in onshore and offshore forms. They can often end up at spots of natural beauty,and are often unpopular with residents. And turbines are not totally harmless-they can interfere with radar,alter climate and kill sea birds.Scotland is building Europe's largest wind farm,which will power 200 ,000 homes. The U.K. 's goal is to generate one-fifth of power from renewable sources,mainly wind,by 2020 .But this may cause problems, because wind is unreliable. According to the passage,which of the following is the most polluting energy resource?A: Petroleum.B: Coal.C: Natural gas.D: Water.
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第三篇Renewable Energy SourcesToday petroleum（石油）provides around 40% of the world's energy needs , mostly fuelling automobiles.Coal is still used,mostly in power stations,to cover one一quarter of our energy needs,but it is the least efficient,unhealthiest and most environmentally damaging fossil fuel（矿物燃料）.Natural gas reserves could fill some of the gap from oil, but reserves of that will not last into the 22nd century either. Most experts predict we will exhaust easily accessible reserves within 50 years.Less-polluting renewable energy sources offer a more practical long-term energy solution. "Renewable"refers to the fact that these resources are not used faster than they can be replaced.Hydroelectric（水力发电的）power is now the most common form of renewable energy, supplying around 20%of world electricity.China's Three Gorges Dam is the largest ever. At five times the size of the US's Hoover Dam , its 26 turbines（涡轮机）will generate theequivalent energy of 18 coal-fired power stations.It will satisfy 3% of China's entire electricity demand.In 2003, the first commercial power station to use tidal（潮汐的）currents in the open sea opened in Norway. It is designed like windmill（风车）,but others take the form of turbines.As prices fall,wind power has become the fastest growing type of electricity generation一 quadrupling（翻两番）worldwide between 1999 and 2005. Modern wind farms consist of turbines that generate electricity.Though it will be more expensive,there is more than enough wind to provide the world's entire energy needs.Wind farms come in onshore and offshore forms.They can often end up at spots of natural beauty,and are often unpopular with residents.And turbines are not totally harmless一they can intertere with radar,alter climate and kill sea birds.Scotland is building Europe's largest wind farm,which will power 200,000 homes.The UK's goal is to generate one-fifth of power from renewable sources, mainly wind,by 2020.But this may cause problems,because wind is unreliable.According to the passage,which of the following is the most polluting energy resource?A:Petroleum. B:Coal.C:Natural gas. D:Water.
考题
共用题干
Renewable Energy SourcesToday petroleum（石油）provides around 40% of the world's energy needs, mostly fuelling automobiles .Coal is still used,mostly in power stations,to cover one-quarter of our energy needs, but it is the least efficient, unhealthiest and most environmentally damaging fossil fuel（矿物燃料）.Natural gas reserves could fill some of the gap from oil,but reserves of that will not last into the 22nd century either. Most experts predict we will exhaust easily accessible reserves within 50 years. Less-polluting renewable energy sources offer a more practical long-term energy solution. "Renewable"refers to the fact that these resources are not used faster than they can be replaced.Hydroelectric（水力发电的）power is now the most common form of renewable energy , supplying around 20% of world electricity.China's Three Gorges Dam is the largest ever. At five times the size of the U. S. 's Hoover Dam,its 26 turbines (涡轮机）will generate the equivalent energy of 18 coal-fired power stations. It will satisfy 3%of China's entire electricity demand.In 2003,the first commercial power station to use tidal（潮汐的）currents in the open sea opened in Norway. It is designed like windmill（风车）,but others take the form of turbines.As prices fall,wind power has become the fastest growing type of electricity generation-quadrupling（翻两番）worldwide between 1 999 and 2005 . Modern wind farms consist of turbines that generate electricity. Though it will be more expensive,there is more than enough wind to provide the world's entire energy needs.Wind farms come in onshore and offshore forms. They can often end up at spots of natural beauty,and are often unpopular with residents. And turbines are not totally harmless-they can interfere with radar,alter climate and kill sea birds.Scotland is building Europe's largest wind farm,which will power 200 ,000 homes. The U.K. 's goal is to generate one-fifth of power from renewable sources,mainly wind,by 2020 .But this may cause problems, because wind is unreliable. Which countly took the lead in making use of tidal currents to produce power in 2003?A: TheU.K.B: China.C: Norway.D: TheU.S.
考题
共用题干
Renewable Energy SourcesToday petroleum（石油）provides around 40% of the world's energy needs, mostly fuelling automobiles .Coal is still used,mostly in power stations,to cover one-quarter of our energy needs, but it is the least efficient, unhealthiest and most environmentally damaging fossil fuel（矿物燃料）.Natural gas reserves could fill some of the gap from oil,but reserves of that will not last into the 22nd century either. Most experts predict we will exhaust easily accessible reserves within 50 years. Less-polluting renewable energy sources offer a more practical long-term energy solution. "Renewable"refers to the fact that these resources are not used faster than they can be replaced.Hydroelectric（水力发电的）power is now the most common form of renewable energy , supplying around 20% of world electricity.China's Three Gorges Dam is the largest ever. At five times the size of the U. S. 's Hoover Dam,its 26 turbines (涡轮机）will generate the equivalent energy of 18 coal-fired power stations. It will satisfy 3%of China's entire electricity demand.In 2003,the first commercial power station to use tidal（潮汐的）currents in the open sea opened in Norway. It is designed like windmill（风车）,but others take the form of turbines.As prices fall,wind power has become the fastest growing type of electricity generation-quadrupling（翻两番）worldwide between 1 999 and 2005 . Modern wind farms consist of turbines that generate electricity. Though it will be more expensive,there is more than enough wind to provide the world's entire energy needs.Wind farms come in onshore and offshore forms. They can often end up at spots of natural beauty,and are often unpopular with residents. And turbines are not totally harmless-they can interfere with radar,alter climate and kill sea birds.Scotland is building Europe's largest wind farm,which will power 200 ,000 homes. The U.K. 's goal is to generate one-fifth of power from renewable sources,mainly wind,by 2020 .But this may cause problems, because wind is unreliable. China's Three Gorges Dam______.A: is the first hydroelectric dam in the worldB: is of the same size as the U.S.'S Hoover DamC: can generate around 3%of world electricityD: is the largest hydroelectric dam in the world
考题
根据以下材料，回答
There is little debate about the firstdevelopment of the energy system of the 22nd century--that most of the energyproduced on a large scale will be in the form of electric power. Thus, most presentconcepts for major long-term energy sources (solar, geothermal, fusion) are basedupon electric power production at central plants.
The second major development is thepotential use of hydrogen as both a basic fuel to replace natural gas and aspart of a general system to convert, store and transmit electric energy overlong district by fuel cells, or it could be used directly as a fuel forcommercial, industrial or transportation purposes.
Although hydrogen seems likely to play amajor role in the future as a form of energy transport and storage, other processesmay also be useful. Here we note only two possibilities.
Flywheels: It appears to be workable toconstruct flywheels of almost any needed size that would be efficientconverters (93-95 percent) in first storing and then releasing electric power.In addition, the kinetic (动力的) energy ofrotation is easily converted to alternating electric power. But the engineeringis at an early stage of development, and a decade or more may pass before this potentialcan be reliably estimated.
Batteries and fuel cells: some of the manybatteries being developed today look quite promising. Within a decade or two, abattery-operated electric auto might even become competitive with today′ s vehicles,at least for driving ranges up to 200 miles. An electric automobile would bepollution-free,and would probably be more energy-efficient than theinternal-combustion (内燃) engine.
A fuel cell (which may be considered a hydridebattery) with about 40 percent conversion efficiency is expected to enter powerproduction on a large scale within about five years. Unlike steam-poweredgenerators, fuel cells can be made large or small and their efficiency inoperation is essentially independent of the loading. Thus they may avoid mostof the distribution costs of electric power as well as provide pollution-fleepower and offer opportunities for using the "waste heat" effectively.
From the passage we can see that thefuel cell might be something ___________.A.with the electric energy stored in itwithout pollution
B.in which chemicals are contained
C.in which certain fuels such as hydrogenare filled
D.like a small steam generator
考题
根据以下材料，回答
There is little debate about the firstdevelopment of the energy system of the 22nd century--that most of the energyproduced on a large scale will be in the form of electric power. Thus, most presentconcepts for major long-term energy sources (solar, geothermal, fusion) are basedupon electric power production at central plants.
The second major development is thepotential use of hydrogen as both a basic fuel to replace natural gas and aspart of a general system to convert, store and transmit electric energy overlong district by fuel cells, or it could be used directly as a fuel forcommercial, industrial or transportation purposes.
Although hydrogen seems likely to play amajor role in the future as a form of energy transport and storage, other processesmay also be useful. Here we note only two possibilities.
Flywheels: It appears to be workable toconstruct flywheels of almost any needed size that would be efficientconverters (93-95 percent) in first storing and then releasing electric power.In addition, the kinetic (动力的) energy ofrotation is easily converted to alternating electric power. But the engineeringis at an early stage of development, and a decade or more may pass before this potentialcan be reliably estimated.
Batteries and fuel cells: some of the manybatteries being developed today look quite promising. Within a decade or two, abattery-operated electric auto might even become competitive with today′ s vehicles,at least for driving ranges up to 200 miles. An electric automobile would bepollution-free,and would probably be more energy-efficient than theinternal-combustion (内燃) engine.
A fuel cell (which may be considered a hydridebattery) with about 40 percent conversion efficiency is expected to enter powerproduction on a large scale within about five years. Unlike steam-poweredgenerators, fuel cells can be made large or small and their efficiency inoperation is essentially independent of the loading. Thus they may avoid mostof the distribution costs of electric power as well as provide pollution-fleepower and offer opportunities for using the "waste heat" effectively.
In which of the following is the use ofthe "waste heat" mentioned?A.The fuel cell.
B.The fly wheel.
C.The steam-powered generator.
D.The internal-combustion engine.
考题
根据以下材料，回答
There is little debate about the firstdevelopment of the energy system of the 22nd century--that most of the energyproduced on a large scale will be in the form of electric power. Thus, most presentconcepts for major long-term energy sources (solar, geothermal, fusion) are basedupon electric power production at central plants.
The second major development is thepotential use of hydrogen as both a basic fuel to replace natural gas and aspart of a general system to convert, store and transmit electric energy overlong district by fuel cells, or it could be used directly as a fuel forcommercial, industrial or transportation purposes.
Although hydrogen seems likely to play amajor role in the future as a form of energy transport and storage, other processesmay also be useful. Here we note only two possibilities.
Flywheels: It appears to be workable toconstruct flywheels of almost any needed size that would be efficientconverters (93-95 percent) in first storing and then releasing electric power.In addition, the kinetic (动力的) energy ofrotation is easily converted to alternating electric power. But the engineeringis at an early stage of development, and a decade or more may pass before this potentialcan be reliably estimated.
Batteries and fuel cells: some of the manybatteries being developed today look quite promising. Within a decade or two, abattery-operated electric auto might even become competitive with today′ s vehicles,at least for driving ranges up to 200 miles. An electric automobile would bepollution-free,and would probably be more energy-efficient than theinternal-combustion (内燃) engine.
A fuel cell (which may be considered a hydridebattery) with about 40 percent conversion efficiency is expected to enter powerproduction on a large scale within about five years. Unlike steam-poweredgenerators, fuel cells can be made large or small and their efficiency inoperation is essentially independent of the loading. Thus they may avoid mostof the distribution costs of electric power as well as provide pollution-fleepower and offer opportunities for using the "waste heat" effectively.
The energy we use most todayis___________A.solar energy
B.geothermal energy
C.hydrogen
D.electricity
考题
A.The Arguments of Sports Executives
B.The Philosophy of Visionary Executives
C.Sports and Television in the 21st Century
D.Sports：A Business
考题
The most important features in the growth of American economy in the early 20th cenruty were（）Athe use of steam and electricity as chief energy,the development of lare corporation and the development of railwayBthe development of large corporation,urbanization and the employment in production of new technologyCthe appearance of airplane,the use of electricity on a large scale and urbanizationDthe rapid development of industry,railway and large cities
考题
The most important features in the growth of American economy in the early 20th cenruty were（）A、the use of steam and electricity as chief energy,the development of lare corporation and the development of railwayB、the development of large corporation,urbanization and the employment in production of new technologyC、the appearance of airplane,the use of electricity on a large scale and urbanizationD、the rapid development of industry,railway and large cities
考题
单选题Toronto's third City Hall came into use in_____.A
the 18th centuryB
the 19th centuryC
the 20th centuryD
the 21st century
考题
问答题Fuel Cells: 21st Century Electricity The 21st century’s leading energy source may very well depend on the development of a technology that was first discovered in 1839. Indeed, many experts believe that the future of electricity generation will not come from further refinement of solar, wind, coal or nuclear energy, but from fuel cells. Among the various types of fuel cells, the ceramic or solid oxide fuel cell promises to achieve the greatest efficiency of conversion of fossil fuels such as gas and coal to electricity while producing only very low levels of pollutants. To this end, a consortium comprising five leading organizations has established Ceramic Fuels Ltd, initially to expand fuel cell research and development and secondly, to bring the technology to commercial application. Ceramic fuel cells are electrochemical devices that directly convert fuels such as gasified coal or natural gas into electricity without the limitation of the Carnot cycle (an ideal thermodynamic cycle in which heat is taken onto a working fluid at a constant upper temperature and rejected at a constant lower temperature). In many respects, fuel cells work like batteries. As long as they are constantly supplied with fuel and oxidant, fuel cells can continuously produce power, removing the need for recharging. Fuel cells offer several advantages over traditional thermal power plants. The major difference between these two power generators is that the chemical energy of the fuel cell is converted directly to electrical power without intermediate conversion first to heat. The efficiency of a coal-fired thermal plant is typically in the range of 30%-35%. In a combined cycle gas turbine system running on natural gas, the maximum efficiency is in the range 45%-50%. Many experts believe high temperature fuel cells could reach efficiencies of 80%-85%. Ceramic fuel cells thus offer a more efficient and less polluting alternative to current power generation technologies. By-products from fuel cells are high quality heat, carbon dioxide and steam. The temperature of the exhaust gases is well above 500℃, meaning that solid oxide fuel cells are very attractive for electricity and heat generation as, in addition to supplying electricity, the leftover amounts of heat created during the process could be used to produce heat for industries, provide hot water supplies or warm buildings. Fuel cell technology is not new. In fact, the principles of fuel cell operation were first reported by British scientist Sir William Grove in 1839. His prototype used dilute sulphuric acid and operated at room temperature. Ceramic fuel cells developed much later, with the first one operating at 1000°C in 1937. Ceramic fuel cells offer many advantages over other energy systems: ● they have the potential to produce electricity efficient from several fuel sources ● they can generate large amounts of electricity ● they are relatively quick to install Fuel cell research and development is extremely competitive worldwide, with the USA, Japan and some European countries leading the charge to commercialize this promising technology. For instance, a Dutch Belgian company has developed a fuel cell for a Volkswagen van and is also working on a larger unit to power a bus. Additionally, a German company is working on a fuel cell for the European space shuttle program and for submarines, while a Canadian company is evaluating a fuel cell to be used in small buses. Recent reports point to promising large international markets for ceramic fuel cells. Prospects for fuel cells in South East Asian markets appear good. Several countries, including Indonesia, Thailand and The Philippines are expected to demonstrate high rates of growth in demand for power an encouraging situation for those countries quick enough to develop and commercialize fuel cell technology. Energy is a vital component of a technology-based society and the growing need for electricity generation by the most efficient method will ensure a promising future for ceramic fuel cell technology. The Ceramic Fuel Cells Ltd initiative represents a major collaborative venture between public and private sectors. It is envisaged that this venture will go a long way towards achieving a greater efficiency of energy use worldwide. Do the following statements reflect the claims of the writer in the Reading Passage? YES if the statement reflects the claims of the writer NO if the statement contradicts the claims of the writer NOT GIVEN if it is impossible to say what the writer thinks about this Statements: 1．Sir William Grove was a physicist. 2．Future transport vehicles may be powered by fuel cells. 3．European companies were first in the race to develop fuel cell technology. 4．Some rapidly developing South East Asian countries will soon market fuel cells. 5．Cooperation between private companies and governments will encourage wider use of efficient energy sources.
考题
单选题The most important features in the growth of American economy in the early 20th cenruty were（）A
the use of steam and electricity as chief energy,the development of lare corporation and the development of railwayB
the development of large corporation,urbanization and the employment in production of new technologyC
the appearance of airplane,the use of electricity on a large scale and urbanizationD
the rapid development of industry,railway and large cities
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