Renewable Energy Sources
Today petroleum provides around 40% of the world’s energy needs, mostly fuelling automobiles. Coal is still used, mostly in pover 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 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.
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.
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 lilling sea birds. Migrating birds may have more luck avoiding them. Scotland is building europe’s largest wind farm, which wil power 200,000 homes. The UK’s goal is to generate onefifth of power from renewable sources, mainly wind, by 2020. But this may cause problems, because wind is unreliable.
1. What are the energy resources that are not renewable according to the article?
A Petroleum and coal.
B Natural gas.
C Wind and water.
D A and B.
2. China's Three Gorges Dam
A is the first hydroelectric dam in the world.
B is of the same size of the US's Hoover Dam.
C is the largest of all the hydroelectric dams in the world.
D supplies around 20% of the world electricity.
3. Which is the country with thefirst commercial power station that makes use of ocean currents produced by tides?
A China.
B Norway.
C England.
D America.
4. 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 be reliable.
D All of the above.
5. According to the article, resources such as wind
A are sustainable but not replaceable.
B are renewable so sustainable.
C are sustainable so renewable.
D are irreplaceable.
答案与题解：
1. D 文章的第一段提到石油 (petroleum)、煤(coal)和天然气(natural gas)三种矿物燃料 (fossil fuel)，并且说这些可采掘到的燃料将在 50年的时间里用完，所以需要开发再生能源，文章后几段提到了水资源和风能这两种 renewable resources。根据这一理解 D是正确选项。
2. C A是错误选项.因为第二段第二句说世界上第一个水利大坝建在英国 ;B是错误的选项，因为该段第五句指出三峡大坝比美国的 Hoover大坝大五倍 ;该段第三句说水力发电为世界提供 20%的电能，所以 D也是错误的选项。该段第四句则明确告诉我们 C是答案。
3. B文章第三段说 2003年挪威首次运营利用潮汐进行发电的商业电站。所以 B是正确选项。
4. D 文章的第四段提到了 A、B、C的内容，所以 D是正确选项。
5. B 这个问题的理解依赖对整篇文章内容的理解。文章的第一段昀后一句说 :refers to the fact that “Renewable”these resources are not used faster than they can be replaced.其意思是 :再生能源消耗的速度很慢，以至于不会被替代。所以这种能源是 sustainable。
译文：
可再生能源
现今，汽油满足了世界上约百分之四十的能源需要，大多用来为汽车提供燃料。煤仍被使用，主要是在发电站，以解决我们四分之一的能源需求。但煤却是最无效率，最不健康，最不环保的矿物燃料。天然气的储量可填补部分石油短缺。但这些储量也不能维持到22世纪。许多专家预计，我们很容易在50年内耗尽可采掘的燃料储备。我们将很快遇到能源危机。我们需要立即发展可持续的方案来为未来提供能源。污染少的可再生能源为我们提供了一个更现实的长期解决方案。这些能源也会对世界上的穷人有益。“可再生”是指这些能源被使用的速度低于其被更新的速度。
2000多年前，中国人和罗马人使用风车。但第一个水电大坝是1870年建于英国。现在的水力发电已是最常见的可再生能源，占世界电力总量的20％。中国刚建成的三峡大坝是最大的一个发电站。它是美国胡佛发电站的5倍大。它的26台涡轮机可产生相当于18个烧煤的发电站所发的电量。它将满足中国电力总需求的3％。令人吃惊的是，有人说，水电站排放大量温室气体、2003年，第一个利用大海上的潮汐能发电的商业电站在挪威建成。它的设计好像一个风车，但其他方面则采用了涡轮的形式。
由于费用降低，风力发电已成为了发展最迅速的一种发电方式——1999年到2005年翻了两番。现代风力农场由发电的涡轮机组成。尽管成本更高，却会有源源不断的风力来满足全世界的所有能量需求。风力农场分向岸和向海两种形式。它们常常会出现在美丽的环境中，并常常人烟稀少。涡轮机也并非百无一害的。它们可干扰雷达信号，并在生态环境中留下痕迹，改变气候，杀死海鸟。迁徙的鸟类可以更幸运地避开它们。苏格兰正在建造欧洲最大的风力农场，可为20万户家庭提供电力。英国的目标是截至2020年达到五分之一的电力来自可再生能源，主要指风能，但这样做也有问题，因为风是不可靠的。
