自然段A

Operating on the same principle as wind turbines, the power in sea turbines comes from tidal currents which turn blades similar to ships propellers, but, unlike wind, the tides are predictable and the power input is constant. The technology raises the prospect of Britain becoming self-sufficient in renewable energy and drastically reducing its carbon dioxide emissions. If tide, wind and wave-power are all developed, Britain would be able to close gas, coal and nuclear plants and export renewable power to other parts of Europe. Unlike wind power which Britain originally developed and then abandoned for 20 years allowing the Dutch to make it a major industry, undersea turbines could become a big export earner to island nations such as Japan and New Zealand.

自然段A：

海洋涡轮发电与风力涡轮发电基于相同的原理，都是利用潮流转动类似船桨的叶片产生动力，但与风力不同的是，潮汐是可预测的，且能量输入是恒定的。这项技术有望使英国在可再生能源方面实现自给自足，并大幅减少二氧化碳排放。如果潮汐、风力和波浪能源都得到开发，英国将能够关闭天然气、煤炭和核电厂，并向欧洲其他地区出口可再生能源。与最初由英国开发后又放弃了20年并使荷兰成为主要产业的风力发电不同，水下涡轮可以成为像日本和新西兰等岛国的重要出口项目。

自然段B

Tidal sites have already been identified that will produce one sixth or more of the UK’s power—and at prices competitive with modern gas turbines and undercutting those of the already ailing nuclear industry. One site alone, the Pentland Firth, between Orkney and mainland Scotland, could produce 10% of the country’s electricity with banks of turbines under the sea, and another at Alderney in the Channel Islands three times the 1,2000 megawatts of Britain’s largest and newest nuclear plant, Sizewell B, in Suffolk. Other sites identified include the Bristol Channel and the west coast of Scotland, particularly the channel between Campbelltown and Northern Ireland.

自然段B：

已经确定了能够产生英国六分之一甚至更多电力的潮汐发电站，并且价格竞争力与现代燃气涡轮发电机相当，甚至低于已经陷入困境的核能行业。只有一个地点，位于奥克尼群岛和苏格兰大陆之间的彭特兰德海峡，就可以通过铺设在海底的涡轮阵列发电，为英国提供10%的电力，而另一个位于根西岛的地点则可以提供英国最大、最新的核电厂Sizewell B三倍的1,200兆瓦电力。其他已确定的地点包括布里斯托尔海峡和苏格兰西海岸，特别是坎贝尔敦和北爱尔兰之间的海峡。

自然段C

Work on designs for the new turbine blades and sites are well advanced at the University of Southampton’s sustainable energy research group. The first station is expected to be installed off Lynmouth in Devon shortly to test the technology in a venture jointly funded by the Department of Trade and Industry and the European Union. AbuBakn Bahaj, in charge of the Southampton research, said: ‘The prospects for energy from tidal currents are far better than from wind because the flows of water are predictable and constant. The technology for dealing with the hostile saline environment under the sea has been developed in the North Sea oil industry and much is already known about turbine blade design, because of wind power and ship propellers. There are a few technical difficulties, but I believe in the next five to ten years we will be installing commercial marine turbine farm. Southampton has been rewarded ￡215,000 over three years to develop the turbines and is working with Marine Current Turbines, a subsidiary of IT power, on the Lynmouth project. EU research has now identified 106 potential sites for tidal power, 80% round the coasts of Britain. The best sites are between islands or around heavily indented coasts where there are strong tidal currents.

自然段C：

南安普敦大学可持续能源研究组在新型涡轮叶片和发电站设计方面的工作已经取得了很大进展。第一座发电站预计将在德文郡的林茅斯附近投入使用，由英国贸易和工业部与欧盟共同资助进行技术测试。负责南安普敦研究的阿布巴克·巴哈杰表示：“与风力发电相比，潮汐能源的前景更好，因为水流是可预测且恒定的。由于北海石油行业的发展，对应对海底恶劣环境的技术已经得到了发展，而关于涡轮叶片设计方面，由于风力发电和船舶螺旋桨的研究已经有了很多成果。虽然还存在一些技术难题，但我相信在未来五到十年内，我们将会安装商业海洋涡轮发电场。南安普敦大学已获得21.5万英镑的资助，用于开发涡轮，同时与IT Power的子公司Marine Current Turbines合作进行林茅斯项目。欧盟的研究已经确定了106个潮汐能源潜力地点，其中80%位于英国海岸。最佳地点位于岛屿之间或弯曲海岸附近，那里的潮流很强劲。”

自然段D

A marine turbine blade needs to be only one third of the size of a wind generator to produce three times as much power. The blades will be about 20 meters in diameter, so around 30 meters of water is required. Unlike wind power, there are unlikely to be environmental objections. Fish and other creatures are thought unlikely to be at risk from the relatively slow-turning blades. Each turbine will be mounted on a tower which will connect to the national power supply grid via underwater cables. The towers will stick out of the water and be lit, to warn shipping, and also be designed to be lifted out of the water for maintenance and to clean seaweed from the blades.

自然段D：

海洋涡轮叶片只需要风力发电机的三分之一大小就能产生三倍的功率。叶片直径约为20米，因此需要约30米的水深。与风力发电不同，海洋涡轮发电不太可能面临环境方面的反对意见。据推测，鱼类和其他生物不太可能受到相对较慢旋转的叶片的威胁。每个涡轮都将安装在一座塔上，通过水下电缆连接到国家电力供应网络。这些塔将突出水面并带有照明，以警示船只，并且设计可从水中抬起进行维护和清除叶片上的海藻。

自然段E

Dr Bahaj has done most work on the Alderney site, where there are powerful currents. The single undersea turbine farm would produce far more power than needed for the Channel Islands and most would be fed into the French Grid and be re-imported into Britain via the cable under the Channel.

自然段E：

巴哈杰博士在根西岛的项目上做了大量工作，那里有强劲的潮流。这个单一的海底涡轮场将产生比海岛需要的电力要多得多，大部分电力将被馈送到法国电网，并通过海底电缆重新进口到英国。

自然段F

One technical difficulty is cavitation, where low pressure behind a turning blade causes air bubbles. These can cause vibration and damage the blades of the turbines. Dr Bahaj said: ‘We have to test a number of blade types to avoid this happening or at least make sure it does not damage the turbines or reduce performance. Another slight concern is submerged debris floating into the blades. So far we do not know how much of a problem it might be. We will have to make the turbines robust because the sea is a hostile environment, but all the signs that we can do it are good.

自然段F：

一个技术难题是气穴现象，即旋转叶片背后的低压区域产生气泡。这些气泡可能引起振动并损坏涡轮的叶片。巴哈杰博士表示：“我们必须测试多种叶片类型，以避免或至少确保不会损坏涡轮或降低性能。另一个小小的担忧是潜入叶片的漂浮碎屑。目前我们还不知道这可能成为多大问题。我们将不得不使涡轮具备坚固性，因为海洋是一个恶劣的环境，但所有迹象显示我们是能够解决这些问题的。”