Marine Renewable Energy (Ocean energy) - IELTS Listening Answers & Explanations
From Cambridge IELTS 14 Academic Listening Test 1 · Part 4 · Questions 31–40
Audio
Questions
Questions 31–40 Note Completion
Complete the notes below.
Write ONE WORD ONLY for each answer.
Marine renewable energy (ocean energy)
Introduction
More energy required because of growth in population and 31
What’s needed:
- renewable energy sources
- methods that won’t create pollution
Wave energy
Advantage: waves provide a 32 source of renewable energy
Electricity can be generated using offshore or onshore systems
Onshore systems may use a reservoir
Problems:
- waves can move in any 33
- movement of sand, etc. on the 34 of the ocean may be affected
Tidal energy
Tides are more 35 than waves
Planned tidal lagoon in Wales:
- will be created in a 36 at Swansea
- breakwater (dam) containing 16 turbines
- rising tide forces water through turbines, generating electricity
- stored water is released through 37, driving the turbines in the reverse direction
Advantages:
- not dependent on weather
- no 38 is required to make it work
- likely to create a number of 39
Problem:
- may ham fish and birds, e.g. by affecting 40 and building up silt
Ocean thermal energy conversion
Uses a difference in temperature between the surface and lower levels
Water brought to the surface in a pipe
Answers & Explanations Summary
| # | Answer | Evidence | Explanation |
|---|---|---|---|
| Q31 | industry | because of the world’s increasing population and expanding industry. | Excerpt/Transcript Explanation: The transcript mentions that more energy is required because of the world's increasing population and expanding industry. Answer Explanation: The answer 'industry' refers to the sector involving economic activities like manufacturing, production, and services. Reason For Correctness: The correct answer is 'industry' because the excerpt indicates that the need for more energy is due to the growth in population and expanding economic activities, which fall under the category of 'industry'. |
| Q32 | constant | This form of energy has plenty of potential, as the source is constant | Excerpt/Transcript Explanation: The transcript highlights that this form of energy has a lot of potential because its source is consistent or unchanging. Answer Explanation: The answer 'constant' means that the energy source remains the same without variation. Reason For Correctness: The correct answer is 'constant' because the excerpt mentions that the source of energy is consistent. In the context of marine renewable energy, having a constant energy source is beneficial for generating electricity continuously without interruptions. |
| Q33 | direction | But the problem with ocean waves is that they’re erratic, with the wind making them travel in every direction. | Excerpt/Transcript Explanation: The transcript mentions that ocean waves move in many different ways because of the wind. Answer Explanation: The answer refers to the way ocean waves can travel in various paths or routes. Reason For Correctness: The correct answer fits perfectly as it directly relates to the rotating and unpredictable movement of ocean waves as described in the provided excerpt. |
| Q34 | floor | Another drawback is that sand and other sediment on the ocean floor might be stopped from flowing normally | Excerpt/Transcript Explanation: The transcript says that sand and other particles on the ocean floor might not move as they normally do. Answer Explanation: The answer 'floor' refers to the bottom part of the ocean where sand and sediments are present. Reason For Correctness: The correct answer matches the context of the excerpt where the movement of sand and sediment at the bottom of the sea is being discussed. The floor of the ocean is where these sediments are located, so it correctly describes the situation mentioned in the text. |
| Q35 | predictable | One major advantage of using the tide, rather than waves, as a source of energy is that it’s predictable | Excerpt/Transcript Explanation: The transcript is saying that using the tide (the regular rise and fall of the sea level) as a source of energy is better than using waves because the tide is more reliable and can be counted on. Answer Explanation: The answer is 'predictable', which means something that can be relied upon to happen or behave in a certain way. Reason For Correctness: The correct answer is 'predictable' because the excerpt states that the tide is more predictable than waves, meaning that the tide follows a regular pattern and can be trusted to behave in a certain way, making it a more reliable source of energy. |
| Q36 | bay | This will be an area of water within a bay at Swansea, sheltered by a U-shaped breakwater, or dam, built out from the coast. | Excerpt/Transcript Explanation: The transcript talks about a specific location for a planned tidal lagoon in Wales. It mentions that it will be situated in an area of water within a bay at Swansea, which is protected by a U-shaped breakwater or dam extending from the coast. Answer Explanation: The answer 'bay' refers to a body of water partially enclosed by land. In this context, it indicates the specific type of location where the planned tidal lagoon in Wales will be situated. Reason For Correctness: The correct answer is 'bay' because it accurately describes the type of water area specified in the excerpt. It fits the context of a sheltered location within a larger body of water, making it the appropriate choice based on the details provided in the text. |
| Q37 | gates | Then, in order to release the stored water, gates in the breakwater are opened. | Excerpt/Transcript Explanation: The transcript mentions that in order to release the stored water, gates in the breakwater are opened. Gates are like doors that can be opened or closed to control the flow of water. Answer Explanation: The answer 'gates' refers to the barriers that can be opened to allow water to flow through. In this context, gates are used to manage the movement of water in the tidal lagoon. Reason For Correctness: The correct answer is 'gates' because it directly aligns with the action described in the excerpt, where gates are opened to release the stored water from the breakwater. This shows that gates play a crucial role in controlling the flow of water for generating electricity. |
| Q38 | fuel | the turbines are operated without the need for fuel | Excerpt/Transcript Explanation: The transcript says that the turbines work without needing anything to make them go. Answer Explanation: The answer 'fuel' means something that is burned to make energy. Reason For Correctness: The correct answer 'fuel' is right because the excerpt tells us that the turbines don't need anything to make them work. Fuel is something that is burned to make things work, so the answer makes sense. |
| Q39 | jobs | that manufacturing the components would create than 2,000 jobs, a big boost to the local economy. | Excerpt/Transcript Explanation: The transcript mentions that creating the components for a particular project would lead to more than 2,000 jobs being available, which would greatly help the local economy. Answer Explanation: The answer refers to the fact that the project is likely to create a considerable number of job opportunities. Reason For Correctness: The correct answer is 'jobs' because it directly corresponds to the excerpt where it is stated that over 2,000 jobs would be created, indicating the positive impact on local employment opportunities. |
| Q40 | migration | On the other hand, there are fears that lagoons might harm both fish and birds, for example by disturbing migration patterns | Excerpt/Transcript Explanation: The transcript mentions concerns that tidal lagoons may cause harm to fish and birds by disturbing their movement from one place to another. Answer Explanation: The answer refers to the act of animals moving from one region to another. Reason For Correctness: The correct answer is 'migration' because it directly relates to the disturbance mentioned in the transcript, where the construction of tidal lagoons might impact the migration patterns of fish and birds. |
Transcript
Producing enough energy to meet our needs has become a serious problem. Demand is rising rapidly, because of the world’s increasing population and expanding industry. Burning fossil fuels, like gas, coal and oil, seriously damages the environment and they’ll eventually run out. For a number of years now, scientists have been working out how we can derive energy from renewable sources, such as the sun and wind, without causing pollution. Today I’ll outline marine renewable energy – also called ocean energy – which harnesses the movement of the oceans.
Marine renewable energy can be divided into three main categories: wave energy, tidal energy and ocean thermal energy conversion, and I’ll say a few words about each one.
First, wave energy. Numerous devices have been invented to harvest wave energy, with names such as Wave Dragon, the Penguin and Mighty Whale, and research is going on to try and come up with a really efficient method. This form of energy has plenty of potential, as the source is constant, and there’s no danger of waves coming to s standstill. Electricity can be generated using onshore systems, using a reservoir, or offshore systems. But the problem with ocean waves is that they’re erratic, with the wind making them travel in every direction. This adds to the difficulty of creating efficient technology: ideally all the waves would travel smoothly and regularly along the same straight line. Another drawback is that sand and other sediment on the ocean floor might be stopped from flowing normally, which can lead to environmental problems.
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The second category of marine energy that I’ll mention is tidal energy. One major advantage of using the tide, rather than waves, as a source of energy is that it’s predictable: we know the exact time of high and low tides for years to come.
For tidal energy to be effective, the difference between high and low tides needs to be at least five metres, and this occurs naturally in only about forty places on Earth. But the right conditions can be created by constructing a tidal lagoon, an area of sea water separated from the sea.
One current plan is to create a tidal lagoon on the coast of Wales. This will be an area of water within a bay at Swansea, sheltered by a U-shaped breakwater, or dam, built out from the coast. The breakwater will contain sixteen hydro turbines, and as the tide rises, water rushes through the breakwater, activating the turbines, which turn a generator to produce electricity. Then, for three hours as the tide goes out, the water is held back within the breakwater, increasing the difference in water level, until it’s several metres higher within the lagoon than in the open sea. Then, in order to release the stored water, gates in the breakwater are opened. It pours powerfully out of the lagoon, driving the turbines in the breakwater in the opposite direction and again generating thousands of megawatts of electricity. As there are two high tides a day, this lagoon scheme would generate electricity four times a day, every day, for a total of around 14 hours in every 24 – and enough electricity for over 150,000 homes.
This system has quite a lot in its favour: unlike solar and wind energy it doesn’t depend on the weather; the turbines are operated without the need for fuel, so it doesn’t create any greenhouse gas emissions; and very little maintenance is needed. It’s estimated that electricity generated in this way will be relatively cheap, and that manufacturing the components would create than 2,000 jobs, a big boost to the local economy.
On the other hand, there are fears that lagoons might harm both fish and birds, for example by disturbing migration patterns, and causing a build-up of silt, affecting local ecosystems.
There are other forms of tidal energy, but I’ll go on to the third category of marine energy: ocean thermal energy conversion. This depends on there being a big difference in temperature between surface water and the water a couple of kilometres below the surface, and this occurs in tropical coastal areas. The idea is to bring cold water up to the surface using a submerged pipe. The concept dates back to 1881, when …