新世纪研究生综合英语unit8教学文案.docx

新世纪研究生综合英语unit8

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Unit8
Power to the people
Almost a century has gone by since humans began exploiting a compelling new way to power the global economy. The switch to fossil fuels prompted促使 an explosion innovation either side of the 1900s.including creations such as the internal combustion engine. Such technologies have since provided the means to drive our thirsty, energy-intensive modern societies.
Today we stand at a similar turning point. Solar power, wind turbines and other sources of clean power--- the preserve of visionaries 有预见的人and enthusiasts little more than a decade ago--- are now poised on the brink of the mainstream, helped in no small part by the environmental deficiencies of fossil fuels. The need to create clean energy has become a pressing concern for policy makers and big business--- not to mention the consumer.
Such thinking is fuelled by the growing realization that all along nature has provided ready-made means to power modern civilizations, namely through the elements. Crucial advances in new technology have these inexhaustible sources cheaper to use with, for example, the cost of solar energy plunging by up to 98 percent over the past 20 years.
In theory, these renewable energy resources are incongruous large. The sun alone provides the means to deliver 7,000times our own energy consumption; blanking just 2.6 percent of the Sahara desert with solar cells could supply our entire needs. Yet for all this impressive potential, renewable energy currently produces just two percent of our total energy output.
However, as the computer industry discovered in the 1980s, rapid growth can swiftly transform a minority sector into a giant capable of dominating our lives. Already companies across the globe are scrambling征服争夺 to become the next Intel or Microsoft of the new energy revolution. Our homes, cities, and workplaces--- our lives--- may be reshaped in ways we can only begin to guess at the solar cell, the wind farm and the electric car enter larger sectors of the marketplace.
Blazing a trail
The sun’s capability to power the planet is phenomenal杰出的. Already a billion-pound business, projections indicate an annual growth rate for the next decade of 14 percent. But the price of solar technology has always been its biggest sticking point, and the cost of solar cells will need to fall by up to 50 percent in order to fully competitive with coal-fired electricity.
Several companies are currently developing a new generation of wafer-thin photovoltaic光电的 solar panels that will slash大量削减 costs still further. Photovoltaics(pv) convert the sun’s heat into electricity, silently and without pollution. They use semi-conductors that send out electrons the instant sunlight reaches them, triggering使触发引起 the flow of electricity. The greater the volume of sunlight, the more electrons are emitted发射或发射出.
Solar power could provide thousands of times more energy than we world currently uses, the earth receiving an unimaginably huge amount of energy way beyond the capabilities of fossil fuels or nuclear fission. In figures, the sun’s continuous power input stands数据 at 200 watts followed by 15 zeros.
Its uses are impressively varied. Solar cells now power satellites, mobilephones, television sets, highway signals and water pumps. Last year the Dutch solar car Nuna broke the world record--- with an average speed of 91 km/h--- in the world Solar challenge, a 3,010-kilometer race across Australia for cars powered by the sun.
A look at the planet’s most conspicuous明显的 consumers reveals that solar energy is finally beginning to make real inroads as an alternative energy. The USA’s Million Solar Roofs Initiative aims to put a million solar systems on the roofs of commercial and residential building by 2010. In addition, 30 states now have official policies encouraging the development of solar energy with financial incentives for investment in the use of PV modules and cells.
Advocates believe that PV could claim to be the simplest and most elegant technology to harness the power of the sun, being easy to install and requiring minimal maintenance. Given this advantages, the future of solar photovoltaics appears bright.
Tapping into water
Harnessing the power of moving water, whether through the natural rhythems of the tide and ocean waves or by means of massive artificial dams, offers another renewable energy source with a major future. Wave power alone has the potential to provide enough power to supply an estimated 1.4 million households in an industrial society.
However, the intrinsic difficulties in harnessing开发 the strength of rough seas have created major headaches for engineers; two wave-power stations in Scotland and Norway have already fallen victim to the sea. Once again though, the biggest hurdle is financial, with construction of turbines at sea expensive, despite the actual energy being plentiful and free.
Further difficulties are caused by the fact that waves refuse to flow in one direction. One solution to this problem has been to fit turbines in a chimney-type seabed structure that can be oriented to face the direction of energy-giving waves.
By contrast, hydroelectric power is well established, producing almost a quarter of the world’s electricity and supplying more than one billion people with power. Hydropower produces energy equivalent to 3.6 billion barrels of oil a year. Electricity is produced by falling water passing through a turbine; dams are often used to ensure water supply can be controlled depending on the demand for power.
However the construction of mighty dams often has huge environmental impacts caused by having to flood large areas, triggering acute damage existing habitats--- the three gorges dam currently under construction in china will see 632 square kilometers inundated洪水泛滥 and1.1 million people facing resettlement. Such obvious deficiencies 缺点aside, hydropower offers a clean, renewable source of energy that offers cheap electricity.
Blowing hot and cold
Wonderfully simple in concept, perfectly practical in reality, wind power has been on the drawing board of energy providers for centuries. Yet its potential has long been hamstrung 不起作用by opponents claiming wind farms spoil the beauty of the landscape. This is compounded加重 by year of under-investment and a lack of political support.
Power is generated by the wind turning massive blades that in turn drive turbines, with the ensuing energy piped to the national grid. Simple. And there are absolutely no destructive by-products. What’s more, vast swathes 长条形地带of the globe provide idol conditions to harness开发 wind power, though of course most coastal and mountainous regions experience enough of the resource to make it visible, at least locally.
In China, estimates place its wind resource at 350,000 megawatts, sufficient to provide the world’s largest national population with electricity today. Britain, the windiest country in Europe, itself endures sufficient brisk breezes to serve its electricity generation three times over. Offshore plants are favoured where the wind is stronger and no one can complain at the intrusion into their environment.
However, as well as the visual impact of wind-farms, some local residents have complained about levels of noise from the turbine gearing systems and blades. Some people are particularly sensitive to low level noise and there is evidence that in certain sites, like Landdinam in Wales, the sound is amplified by some sort of resonance within the valley. Other objects include interference with television and radio reception, negative impacts on local tourism and property values, and the potential disruption扰乱 to wildlife, especially birds.
Hydrogen time-bomb
High hopes are pinned or the fuel cell, a technology forecast to reshape the world energy economy, and adds-on to power transport-systems of tomorrow by replacing petro. Again, its green credentials证书 are indisputable: fuel cells release nothing more damaging into the atmosphere than water vapour. Onlike oil, gas and coal it does not produce carbon dioxide, and has the advantage of being twice as efficient as conventional engines in converting chemical fuels into power.
Fuel cells also hold potential for developing nations because they are almost as economical on a small-scale as a large one, require little maintenance and no recharging. In simple terms, fuel cells work using a chemical reaction to produce electricity from hydrogen, which can be derived from such sources as natural gas and methanol甲醇. Governments are understandably keen on a technology that offers the possibility of true”zero emission” energy.
With the cost of power failures to it economies greater than ever, off-grid sources such as stationary fuel cells could soon become commercial necessities.
Be oriented to调整适应
Be pinned on 信赖，附属于
Blaze a trail 开路先锋，带头
Blow hot and cold犹豫不决
Convert into 变换转变
Make inroads 涉足另一个新领域
On the drawing board在设计阶段
Solar panel 太阳能电池板
Tap into开发着手
Zero emission 零排放
选择题
1、 At the press conference, they were scrambling攀登 to give the impression that the situation was in control.
A/searching B/struggling C/crowding D/exiting
2、 Written off again and again, he has proved phenomenon in resilience and political craftiness.
A/notable B/tangible C/extraordinary D/sensible
3、 This news has sent a wave of panic through the world which to me seems way out of proportion.
A/ far B/mean C/simply D/away
4、 Downtown business owners say that they want the city’s homeless shelter moved to a conspicuous location.
A/confronted B/ fantastic C/confident D/noticeable
5、 Over the past year, Linux has significant inroads into embedded designs requiring rich, high performance networking.
A/ Made money B/made achievement C/ made advances D/ made progress
6、 The important thing is to harness growth to self-knowledge, a ready acceptance of change, swift-moving business practice and sound judgment.
A/ make use control produce escape
7、 We are the ones willing and able to run an obstacle course filled with hurdles that we must complete before anyone else.
Barriers bless reports handouts
8、 I haven’t been able to orient my ideas to the new conditions since I worked abroad three months.
Change adjust direct organize
9、 The company office was inundated with telegrams of congratulations on the tenth anniversary of its foundation.
Overjoyed flooded crowded satisfied
10、 He had draw a contradictory conclusion in his thesis because he pinned his faith on an absurdity.
Decided practiced depended placed
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