Tidal power

Undersea turbines which produce electricity from the tides are set to become an important source of renewable energy for Britain. It is still too early to predict the extent of the impact they may have. but all the signs are that they will play a significant role in the future.

1. 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 the 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 power 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.
2. 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 Pendand 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 1,200 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 Campbeltown and Northern Ireland.
3. 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. AbuBakr 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 nine to ten years we will be installing commercial marine turbine farms.’ Southampton has been awarded £2’l5.U.`D 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 1GB potential sites for tidal powen BG% round the coasts of Britain. The best sites are between islands or around heavily indented coasts where there are strong tidal currents.
4. 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 metres in diameter so around 30 metres 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.
5. Dr Baha has done most work on the Alderrney 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.
6. One technical difficulty is cavitations, 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.

1. Giải thích từ vựng

• Undersea (a) /ˌʌn.dəˈsiː/ dưới mặt biển

Eg: The latter will include nuclear power generation, undersea activities, defence and space exploration.

• Work on (phrasal verb) Phát triển, cải thiện

Eg: His dancing technique is good, but he needs to work on his stamina.

I need to work on my pronunciation if I’m to pass the exam.

Một số từ đồng nghĩa: 

• Improve His health has improved dramatically since he started exercising.
• get better The first part of the book isn’t very good but it gets better.
• Rally The team played badly in the first half but rallied in the second.
• Recover We are still waiting for the economy to recover.
• look up Our financial situation is looking up.
• pick up Business is really beginning to pick up.

• Sustainable (a) /səˈsteɪ.nə.bəl/ bền vững, lâu dài

Eg: A large international meeting was held with the aim of promoting sustainable development in all countries.

The website encourages sustainable fashion through swapping.

It would not be sustainable in the long term.

• Install (v) /ɪnˈstɔːl/ lắp đặt (hệ thống máy móc, hệ thống sưởi…)/ cài đặt

Eg: The plumber is coming tomorrow to install the new washing machine.

We will install your washing machine free of charge/for free.

They gave us a long spiel about why we needed to install double glazing in our house.

• Current (n) /ˈkʌr.ənt/ dòng (nước); luồng (gió, không khí); (điện học) dòng điện

Eg: He was swept out to sea by the strong current.

• Self-sufficient (a) /ˌself.səˈfɪʃ.ənt/ tự túc, tự cung cấp, không phụ thuộc, độc lập

Eg: The programme aims to make the country self-sufficient in food production and to cut energy imports.

They were busy with growing vegetables and all the other chores of a self-sufficient rural life.

• Site (n)  /saɪt/ nơi, chỗ, vị trí

Eg: The company hasn’t yet chosen the site for the new hospital.

This is the site of the accident.

• Competitive (a) /kəmˈpet.ɪ.tɪv/ có tính cạnh tranh, đua tranh

Eg: Any new company is seen as an invader in an already competitive market.

If we have to lower our prices to remain competitive, we will.

• Undercut (v) /ˌʌn.dəˈkʌt/ đưa ra giá rẻ hơn, đưa ra điều kiện dễ hơn

Eg: Big supermarkets can undercut all rivals, especially small family-owned shops.

Large supermarkets can undercut their smaller rivals.

•  Ailing (a) /ˈeɪ.lɪŋ/ hỏng hóc, có vấn đề, ốm yếu

Eg: Ted asked me if I could help him fix his ailing car.

• Venture (n)  /ˈven.tʃər/ việc mạo hiểm, việc liều lĩnh/ sự đầu cơ 

Eg: She advised us to look abroad for more lucrative business ventures.

There are many joint ventures between American and Japanese companies.

• Jointly (adv) /ˈdʒɔɪnt.li/ cùng, cùng nhau, cùng chung 

Eg: The Channel Tunnel was jointly funded by the French and British.

The tenants are all jointly responsible for the rent.

The school will involve parents in jointly developing the local plan.

• Hostile (a) /ˈhɒs.taɪl/ thù địch, chống đối

Eg: The president had a hostile reception in Ohio this morning.

There has been a hostile reaction to the government’s proposed tax increases.

• Saline (a) /ˈseɪ.laɪn/ có muối; có tính chất như muối; mặn (nước, suối…)

Eg: Wash the lenses in saline solution.

• Unlikely (a) không chắc, không chắc sẽ xảy ra

Eg: The lack of evidence means that the case is unlikely to go to court.

The government is unlikely to agree to the rebels’ demands for independence.

• Relatively (adv) /ˈrel.ə.tɪv.li/  tương đối 

Eg: These people are living on relatively low incomes.

It is relatively easy for newcomers to pick off the most lucrative business and ignore the rest.

• Mount (v) /maʊnt/ cắm vào, dán vào, đóng vào

Eg: The children’s work has been mounted on coloured paper and put up on the walls of the classroom.

• Stick out (phrasal verb) lòi ra, nhô lên (trên bề mặt)

Eg: There was a handkerchief sticking out of his jacket pocket.

• Light (v) thắp đèn, thắp sáng

Eg: The stage had been lit with candles.

Fireworks lit up the sky.

Past participle: lit

•  Maintenance (n)  /ˈmeɪn.tən.əns/ sự bảo dưỡng, sự bảo quản

Eg: Old houses need a lot of maintenance.

There are thorough maintenance checks on each plane before take-off.

The magazine offers tips on cutting your house maintenance costs.

• Feed (v)  cung cấp (chất liệu cho máy…)

Eg: The vegetables are fed into the machine at this end.

A member of staff had been feeding the newspaper information/feeding information to the newspaper.

Quá khứ: fed

Collocation 

• Feed sth into sth

•  Cavitation (n) /ˌkæv.ɪˈteɪ.ʃən/ sự tạo ra lỗ hổng; sự tạo ra lỗ trống

Eg: Cavitation can occur at the trailing edge of ship propellers, and in liquids subject to powerful sound waves.

Cavitation bubbles oscillations are more pronounced at high laser power.

• Vibration (n) /vaɪˈbreɪ.ʃən/  sự lúc lắc, sự chấn động

Eg: Vibrations were felt hundreds of miles from the centre of the earthquake.

Aircraft manufacturers want to reduce vibration for the sake of safety.

• Submerge (v) /səbˈmɜːdʒ/ dìm xuống nước, nhận chìm xuống nước

Eg: Take a normal breath and completely submerge yourself.

• Debris (n)  /ˈdeb.riː/ mảnh vỡ, mảnh vụn 

Eg: Debris from the aircraft was scattered over a large area.

After the tornado, debris from damaged trees and houses littered the town.

• Robust (a)  /rəʊˈbʌst/ khoẻ mạnh, mạnh mẽ

Eg: The house blend of coffee is particularly robust.

• Reference (n) /ˈref.ər.əns/ sự ám chỉ, sự nói đến, sự nhắc đến

Eg: Knowing what had happened, I avoided making any reference to weddings.

I am writing to you with reference to the job advertised in yesterday’s newspaper.

Collocation 

• make reference to sth He didn’t make any reference to the new product in his report.
• reference to sth Comparative advertising is where one trader advertises his goods by reference to another trader’s goods.

•  Reliable (a)  /rɪˈlaɪ.ə.bəl/ chắc chắn, đáng tin cậy; xác thực 

Eg: What is the most reliable method of contraception?

A great deal of effort has gone into making the software reliable.

• Cut down (phrasal verb) cắt giảm (việc sử dụng/ số lượng)

Eg: I’m trying to cut down on caffeine.

Collocation 

• cut down on sth The supermarket chain has promised to cut down on packaging.

•  Closure (n) /ˈkləʊ.ʒər/  sự kết thúc, sự đóng cửa (của công ty, nhà máy)

Eg: Many elderly people will be affected by the library closures.

• Income (n) /ˈɪŋ.kʌm/ thu nhập, doanh thu, lợi tức 

Eg: Average incomes have risen by 4.5 percent over the past year.

More help is needed for people on low incomes.

I haven’t had much income from my stocks and shares this year.

• Resistance (n)  /rɪˈzɪs.təns/ sự chống cự, sự kháng cự

Eg: There’s a lot of resistance to the idea of a united Europe.

He was famed for his stubborn resistance and his refusal to accept defeat.

• Compensate (v) /ˈkɒm.pən.seɪt/ bù, đền bù, bồi thường

Eg: Victims of the crash will be compensated for their injuries.

Nothing will ever compensate for his lost childhood.

Collocation 

• be compensated for:  Employees must be compensated for any extra hours worked.

•  Vicinity (n) /vɪˈsɪn.ə.ti/ vùng lân cận

Eg: There are several hotels in the immediate vicinity of the station.

1. Luyện tập

Bài 1: Chọn từ trong khung để hoàn thành các câu bên dưới

saline	vibration	competitive	closure	hostile
compensate	undercut	working on	vicinity	jointly

1. The service is still not satisfactory, but the company say they’re …………… it.
2. What is your strategy for helping the company stay …………………. in a global market?
3. They claim to ……………… their competitors by at least five percent.
4. The new project will be ………………….. managed by the two companies.
5. The security forces exercised great restraint by not responding to ……………. attacks and threats.
6. We could see that there were several open Wi-Fi networks in the ……………..
7. I took her swimming to …………………. for having missed out on the cinema.
8. The newspaper article touched a raw nerve – people still resent the ……………….. of the local school.
9. We know that prolonged exposure to ………………. can weaken aircraft components.
10. Wash leaves again in 1% …………………… solution for 3-5 minutes to remove microbes.

Bài 2: Chọn đáp án đúng để điền vào chỗ trống

1. Such unpopular legislation is …………………. to be introduced before the next election.                                A. unlikely             B. ailing
2. The …………………. company shut down two of its smaller plants in an attempt to trim costs.                        A. hostile              B. ailing
3. With debts of $4 million and a monthly payroll of $1.2 million, the ……………. is clearly heading for trouble.  A. venture              B. vibration
4. The money I get from teaching evening classes provides a supplement to my main …………………..             A. income               B. closure
5. Following a determined …………. in the east, there was eventually a popular uprising in the capital                A. vicinity                 B. resistance
6. She was taken to hospital after being ………….. in an icy river for 45 minutes.                                                 A. compensated        B. submerged
7. Emergency teams are still clearing the ……………… from the plane crash.                                                      A. debris              B. venture
8. They recall the village as a tough but proudly ………….. place, with no roads, electricity or running water.         A. self-sufficient       B. ailing
9. The boat drifted with the ………………. until it was miles from shore.                                A. current               B. maintenance
10. She ……………………. the copper lamp on her desk.                                                        A. undercuted          B. lit
11. They’re planning to develop the whole ………………. into a shopping complex.               A. current              B. site
12. When we …………………. the central heating, we put a radiator in every room.               A. undercuted       B. installed
13. We must improve the built environment through …………………. design and greener buildings.           A. competitive                 B. sustainable
14. We are only just beginning to address ourselves to the extraction of ……….. resources.                 A. competitive                B. undersea
15. The third candidate for the party leadership is a ………… unknown quantity.                                    A. relatively                    B. jointly
16. The surveillance camera is …………… above the main door.                                                          A. mounted                   B. undercuted
17. There was a packet of something ………………….. of his pocket.                                                A. sticking out              B. working on
18. She used to work 50 hours a week, but recently she’s ……………….                            A. cut down               B. work on
19. Price alone is not a ………………… indicator of quality.                                                A. unlikely                   B. reliable
20.  The new ships, propelled by gas turbines, require less …………… than older, steam-driven ones.       A. venture                       B. maintenance
21. Special attention is then paid to the conditions of incipient ……………… and to saturation by transient bubbles.        A. vibration         B. cavitation
22. Several small streams ……………. into the river near here.                          A. feed                         B. mount
23. She made a veiled ……………….. to her former employer.                           A. closure           B. reference
24. Exports will continue to be bolstered by the ………………… economy.        A.  robust            B. sustainable

Bài 1: 

1.working on 2. competitive 3. undercut 4. jointly 5. hostile 

6. vicinity 7. compensate 8. closure 9. vibration 10. saline 

Bài 2: 

1.A 2. B 3. A 4. A 5. B

6. B 7. A 8. A 9. A 10. B
7. B 12. B 13. B 14. B 15.A
8. A 17. A 18. A 19. B 20. B
9. B 22. A 23. B                    24. A