IELTS Reading: Thách Thức Của Năng Lượng Tái Tạo – Đề Thi Mẫu Có Đáp Án Chi Tiết

Mở Bài

Chủ đề năng lượng tái tạo và việc tích hợp chúng vào lưới điện quốc gia là một trong những nội dung xuất hiện ngày càng thường xuyên trong kỳ thi IELTS Reading. Với sự quan tâm toàn cầu về biến đổi khí hậu và phát triển bền vững, chủ đề này không chỉ mang tính thời sự cao mà còn chứa đựng nhiều từ vựng học thuật quan trọng mà các thí sinh cần nắm vững.

Trong bài viết này, bạn sẽ được trải nghiệm một bộ đề thi IELTS Reading hoàn chỉnh với ba passages có độ khó tăng dần, từ Easy đến Hard. Bộ đề bao gồm đầy đủ 40 câu hỏi theo đúng format chuẩn IELTS, bao gồm nhiều dạng câu hỏi đa dạng như Multiple Choice, True/False/Not Given, Matching Headings, Summary Completion và nhiều dạng khác. Mỗi câu hỏi đều được thiết kế dựa trên những đề thi thực tế từ Cambridge IELTS và các nguồn uy tín.

Sau phần đề thi, bạn sẽ tìm thấy đáp án đầy đủ kèm theo giải thích chi tiết, giúp bạn hiểu rõ cách paraphrase, xác định từ khóa và áp dụng chiến lược làm bài hiệu quả. Ngoài ra, phần từ vựng được tổng hợp theo từng passage sẽ giúp bạn mở rộng vốn từ học thuật và chuẩn bị tốt hơn cho kỳ thi.

Bộ đề này phù hợp cho học viên có trình độ từ band 5.0 trở lên, đặc biệt hữu ích cho những ai đang hướng tới band điểm 7.0-8.0.

1. Hướng Dẫn Làm Bài IELTS Reading

Tổng Quan Về IELTS Reading Test

IELTS Reading Test kéo dài trong 60 phút và bao gồm 3 passages với tổng cộng 40 câu hỏi. Mỗi passage có độ dài khoảng 700-900 từ và độ khó tăng dần. Điều quan trọng là bạn phải tự quản lý thời gian hiệu quả vì không có thời gian thêm để chuyển đáp án.

Phân bổ thời gian khuyến nghị:

• Passage 1 (Easy): 15-17 phút
• Passage 2 (Medium): 18-20 phút
• Passage 3 (Hard): 23-25 phút

Lưu ý rằng đây chỉ là gợi ý – bạn nên dành nhiều thời gian hơn cho Passage 3 vì nó thường khó nhất và chứa nhiều câu hỏi đòi hỏi suy luận sâu.

Các Dạng Câu Hỏi Trong Đề Này

Bộ đề thi này bao gồm các dạng câu hỏi phổ biến nhất trong IELTS Reading:

1. Multiple Choice – Câu hỏi trắc nghiệm với 3-4 lựa chọn
2. True/False/Not Given – Xác định thông tin đúng, sai hay không được đề cập
3. Matching Information – Nối thông tin với đoạn văn tương ứng
4. Sentence Completion – Hoàn thiện câu với từ trong bài đọc
5. Matching Headings – Nối tiêu đề với đoạn văn
6. Summary Completion – Điền từ vào đoạn tóm tắt
7. Short-answer Questions – Trả lời ngắn theo yêu cầu

Mỗi dạng câu hỏi đều yêu cầu kỹ năng đọc hiểu khác nhau, từ scanning (đọc lướt tìm thông tin cụ thể) đến skimming (đọc lướt nắm ý chính) và detailed reading (đọc kỹ để hiểu sâu).

Chiến lược làm bài IELTS Reading hiệu quả với phân bổ thời gian cho ba passages

2. IELTS Reading Practice Test

PASSAGE 1 – The Rise of Solar and Wind Power

Độ khó: Easy (Band 5.0-6.5)

Thời gian đề xuất: 15-17 phút

Over the past two decades, renewable energy sources have experienced remarkable growth across the globe. Among these, solar and wind power have emerged as the most prominent alternatives to traditional fossil fuels. This transition represents not merely a technological shift but a fundamental reimagining of how societies generate and consume electricity.

Solar photovoltaic technology, which converts sunlight directly into electricity, has seen costs plummet by more than 90% since 2010. This dramatic price reduction has made solar power economically competitive with coal and natural gas in many regions. Large-scale solar farms now dot landscapes from the deserts of California to the plains of Spain, each consisting of thousands of panels arranged in carefully designed patterns to maximize energy capture. Meanwhile, rooftop solar installations have become increasingly common on residential and commercial buildings, allowing individual property owners to generate their own electricity and sometimes even sell excess power back to the grid.

Wind power has followed a similar trajectory. Modern wind turbines stand as tall as 200 meters and feature blades that can span the length of a football field. These impressive structures harness the kinetic energy of moving air and convert it into electrical power with remarkable efficiency. Offshore wind farms, positioned in coastal waters where winds blow stronger and more consistently than on land, have become particularly attractive investments. Countries like Denmark and the United Kingdom have become world leaders in offshore wind development, with some regions now generating more than half their electricity from wind on particularly blustery days.

The environmental benefits of these technologies are substantial. Unlike coal or natural gas plants, solar panels and wind turbines produce zero emissions during operation. They require no fuel, create no air pollution, and contribute nothing to climate change once installed. A single wind turbine can displace approximately 1,500 tons of carbon dioxide annually – equivalent to planting roughly 40,000 trees. The land beneath wind turbines can often continue to be used for agriculture, a practice known as dual-use farming, which provides additional income for rural landowners.

However, these renewable sources come with inherent challenges that complicate their integration into existing electrical grids. The most significant issue is intermittency – the fact that solar panels only generate electricity when the sun shines, and wind turbines only turn when the wind blows. This variability stands in stark contrast to conventional power plants, which can produce steady, predictable amounts of electricity 24 hours a day. On a cloudy, calm day, a region heavily dependent on renewables might suddenly find itself short of power. Conversely, on a particularly sunny and windy day, the system might generate far more electricity than needed, potentially overloading transmission lines.

Grid operators – the professionals responsible for maintaining the balance between electricity supply and demand – face increasingly complex challenges as renewable energy penetration increases. Traditional grids were designed for a unidirectional flow of electricity, from large centralized power plants to distributed consumers. Renewable energy systems, by contrast, are often decentralized, with thousands of solar installations and wind farms feeding electricity into the grid at various points. This creates a multidirectional flow that requires sophisticated monitoring and control systems.

Energy storage emerges as a critical solution to the intermittency problem. Battery systems, particularly lithium-ion batteries, can store excess renewable energy when production exceeds demand and release it when needed. Australia’s Hornsdale Power Reserve, a massive battery installation paired with a wind farm, has demonstrated the technical feasibility of this approach. When completed in 2017, it was the world’s largest lithium-ion battery and has since helped stabilize South Australia’s electricity grid while reducing costs. However, storage systems add significant expense to renewable energy projects and current battery technology cannot economically store electricity for periods longer than a few hours.

Another approach involves improving grid flexibility through enhanced interconnections between regions. Long-distance transmission lines can transport electricity from areas where renewable resources are abundant to regions where they are scarce. When the wind is not blowing in one location, it might be generating strong power elsewhere. These interconnected systems require substantial investment in new infrastructure and often face political and environmental opposition from communities concerned about large transmission towers crossing their landscapes.

Demand response programs represent yet another strategy. These initiatives encourage or incentivize consumers to adjust their electricity usage to match renewable energy availability. For example, electric vehicle owners might be encouraged to charge their cars during midday when solar generation peaks, or industrial facilities might shift energy-intensive processes to periods of high renewable output. Smart meters and advanced communication technologies enable this level of coordination between suppliers and consumers.

Looking forward, experts agree that successfully integrating high levels of renewable energy will require a multifaceted approach combining improved forecasting, expanded storage capacity, enhanced grid infrastructure, and more sophisticated demand management. The technical challenges are substantial but not insurmountable. Countries like Germany and Portugal have already achieved periods where renewables supplied 100% of electricity demand, demonstrating that ambitious renewable energy targets are achievable with proper planning and investment.

Questions 1-13

Questions 1-5: Multiple Choice

Choose the correct letter, A, B, C or D.

1. According to the passage, solar photovoltaic costs since 2010 have
A. remained relatively stable
B. decreased by approximately 90%
C. increased due to higher demand
D. fluctuated unpredictably

2. Modern wind turbines are described as being
A. shorter than traditional structures
B. less efficient than older models
C. as tall as 200 meters
D. unsuitable for offshore locations

3. The passage states that dual-use farming allows
A. turbines to generate more electricity
B. agricultural activities to continue beneath turbines
C. farmers to operate power plants
D. crops to grow faster

4. The main difference between renewable and conventional power plants is
A. their physical size
B. their construction costs
C. the predictability of their output
D. their environmental impact only

5. Grid operators’ jobs have become more complex because
A. renewable systems create multidirectional electricity flow
B. they need to work longer hours
C. power plants are located too far away
D. consumers use more electricity than before

Questions 6-9: True/False/Not Given

Do the following statements agree with the information given in the passage?

Write:

• TRUE if the statement agrees with the information
• FALSE if the statement contradicts the information
• NOT GIVEN if there is no information on this

6. Rooftop solar installations allow property owners to sell excess electricity back to the grid.

7. Offshore wind farms are less productive than land-based wind farms.

8. A single wind turbine can eliminate the need for 40,000 trees.

9. Australia’s Hornsdale Power Reserve was the world’s most expensive battery project.

Questions 10-13: Sentence Completion

Complete the sentences below.

Choose NO MORE THAN TWO WORDS from the passage for each answer.

10. Solar panels and wind turbines produce __ during their operation.

11. The problem of intermittency refers to the fact that renewable energy production is dependent on __ conditions.

12. Traditional electrical grids were designed for electricity to flow in a __ direction.

13. __ programs encourage consumers to adjust their electricity usage to match renewable energy availability.

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PASSAGE 2 – Technical Challenges in Grid Integration

Độ khó: Medium (Band 6.0-7.5)

Thời gian đề xuất: 18-20 phút

The integration of renewable energy sources into established electrical grids represents one of the most significant engineering challenges of the twenty-first century. While the previous passage outlined basic concepts, the technical realities involve intricate interactions between physics, economics, and policy. Understanding these complexities is essential for appreciating both the obstacles and potential solutions in the transition toward sustainable energy systems.

At the heart of grid management lies the principle of instantaneous balance – the requirement that electricity generation must precisely match consumption at every moment. This balance is not merely a matter of convenience but a physical necessity. Electrical grids operate at specific frequencies (50 Hz in most of the world, 60 Hz in North America), and even minor deviations can damage sensitive equipment or trigger cascading failures that lead to widespread blackouts. Traditional power plants achieve this balance through governor systems that automatically adjust output in response to frequency fluctuations. When demand increases, frequency drops slightly, prompting generators to increase production. This mechanical inertia inherent in spinning turbines provides crucial grid stability.

Renewable energy sources, particularly solar photovoltaic systems and modern wind turbines, fundamentally lack this mechanical inertia. They connect to the grid through power electronics called inverters, which convert the direct current produced by solar panels or the variable frequency output of wind turbines into grid-compatible alternating current. While this technology functions effectively, it responds differently to grid disturbances than traditional generators. This distinction becomes critical as renewable energy penetration increases. System operators express concern about maintaining grid stability when renewables comprise more than 50% of generation capacity, a threshold that several regions are approaching or have already exceeded during certain periods.

The spatial distribution of renewable resources adds another layer of complexity. Wind and solar energy are not uniformly available across geographic regions. Coastal areas and elevated terrain typically offer superior wind resources, while equatorial and desert regions receive the most consistent solar radiation. Consequently, optimal renewable energy generation often occurs far from major population centers where electricity demand is concentrated. This geographic mismatch necessitates significant investment in transmission infrastructure to transport power over long distances.

High-voltage direct current (HVDC) transmission technology has emerged as a preferred solution for long-distance power transmission. Unlike conventional alternating current (AC) transmission, HVDC experiences lower electrical losses over extended distances and can connect asynchronous grids operating at different frequencies. China has become a global leader in HVDC deployment, constructing ultra-high-voltage lines spanning thousands of kilometers to transport renewable energy from remote wind and solar installations to coastal megacities. However, HVDC systems require expensive converter stations at each end and face significant permitting challenges related to land use and environmental concerns.

Forecasting renewable energy production presents yet another technical challenge with substantial operational implications. While weather prediction has improved dramatically, accurately forecasting solar and wind output 24-48 hours in advance remains difficult, particularly during transitional weather patterns. Probabilistic forecasting methods that provide ranges of likely outcomes rather than single predictions have gained traction, allowing grid operators to prepare for multiple scenarios. Machine learning algorithms trained on historical weather and production data show promise in improving forecast accuracy, but unexpected weather events can still cause significant deviations between predicted and actual generation.

The ramp rate limitation of conventional power plants further complicates renewable integration. When cloud cover suddenly reduces solar output or wind speeds drop unexpectedly, backup generation must quickly increase production to compensate. However, traditional thermal power plants (coal, natural gas, nuclear) cannot instantly change their output. Coal plants may require hours to significantly adjust production, while combined-cycle gas turbines can ramp somewhat faster but still need 10-30 minutes for substantial changes. This mismatch between renewable variability and conventional plant flexibility creates periods of grid vulnerability.

Ancillary services – the various functions required to maintain grid reliability beyond simple energy production – become increasingly valuable and complex in renewable-heavy systems. These services include frequency regulation (maintaining the correct electrical frequency), voltage support (keeping voltage within acceptable ranges), and spinning reserves (generation capacity that can quickly respond to unexpected outages). Traditional power plants provide many of these services naturally through their physical characteristics, but renewable installations must use sophisticated control systems to deliver equivalent functionality.

Grid-scale battery storage has evolved from a theoretical concept to commercial reality, yet challenges remain. The lithium-ion batteries that dominate current installations excel at providing short-duration services like frequency regulation but become economically prohibitive for storing energy across multiple hours or days. Alternative technologies including flow batteries, compressed air energy storage, and pumped hydroelectric storage offer longer duration capabilities but face geographical constraints or lower round-trip efficiency (the percentage of stored energy that can be recovered for use).

The phenomenon of negative electricity prices illustrates the economic distortions that can occur with high renewable penetration. During periods of excess renewable generation, particularly in regions with inflexible baseload nuclear or coal plants that cannot easily reduce output, electricity prices can fall below zero. In these situations, generators essentially pay consumers to take electricity, creating perverse incentives that undermine market efficiency. This occurs with increasing frequency in markets like California and Germany, highlighting the need for more flexible market designs that properly value grid services beyond simple energy delivery.

Distributed energy resources (DERs) – including rooftop solar, small-scale battery storage, and electric vehicles – add both opportunities and complications to grid management. These numerous small installations collectively represent significant generation and storage capacity, but coordinating thousands or millions of independent units requires new technological approaches. Virtual power plants that aggregate DERs through software platforms demonstrate how distributed resources might be orchestrated to provide grid services, though regulatory frameworks often lag behind technological capabilities.

Looking toward the future, experts identify several promising technological pathways. Synthetic inertia – using power electronics to simulate the stabilizing effects of mechanical inertia – shows potential for maintaining grid stability with high renewable penetration. Green hydrogen production, which uses excess renewable electricity to split water molecules, offers a means of converting surplus generation into storable chemical energy. Advanced grid control systems employing artificial intelligence could optimize complex systems with thousands of variable inputs faster and more effectively than human operators.

The transition to renewable-dominant grids represents not a single technical challenge but an interconnected web of engineering, economic, and institutional obstacles. Solutions will likely vary by region depending on local resources, existing infrastructure, and policy priorities. However, the increasing technical sophistication of grid management tools and the steady cost decline of enabling technologies suggest that these challenges, while significant, are ultimately surmountable.

Questions 14-26

Questions 14-18: Yes/No/Not Given

Do the following statements agree with the claims of the writer in the passage?

Write:

• YES if the statement agrees with the claims of the writer
• NO if the statement contradicts the claims of the writer
• NOT GIVEN if it is impossible to say what the writer thinks about this

14. The requirement for instantaneous balance between generation and consumption is primarily an economic consideration.

15. Traditional power plants provide grid stability through mechanical inertia.

16. System operators are confident about maintaining grid stability when renewables exceed 50% of capacity.

17. HVDC transmission technology is more efficient than AC transmission for long distances.

18. Machine learning algorithms have completely solved the problem of renewable energy forecasting.

Questions 19-23: Matching Information

Match each description with the correct technology or concept (A-G).

You may use any letter more than once.

A. Lithium-ion batteries
B. HVDC transmission
C. Combined-cycle gas turbines
D. Flow batteries
E. Virtual power plants
F. Synthetic inertia
G. Green hydrogen production

19. Can ramp up production faster than coal plants but still require 10-30 minutes

20. Aggregate distributed energy resources through software platforms

21. Dominate current installations but are not cost-effective for long-duration storage

22. Uses renewable electricity to create storable chemical energy

23. Employs power electronics to replicate stabilizing effects

Questions 24-26: Summary Completion

Complete the summary below.

Choose NO MORE THAN TWO WORDS from the passage for each answer.

Renewable energy integration faces multiple technical challenges. The geographic distribution of resources creates a 24. __ between generation locations and demand centers. When renewable output suddenly decreases, the 25. __ of conventional plants limits how quickly they can compensate. Additionally, during excess generation periods, 26. __ can occur, where generators pay consumers to take electricity.

Công nghệ truyền tải điện HVDC hiện đại kết nối các nguồn năng lượng tái tạo với thành phố

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PASSAGE 3 – Policy Frameworks and Market Mechanisms for Renewable Integration

Độ khó: Hard (Band 7.0-9.0)

Thời gian đề xuất: 23-25 phút

The successful integration of renewable energy into national electrical grids transcends purely technical considerations, requiring carefully designed policy frameworks and market mechanisms that align economic incentives with operational realities. As renewable energy penetration approaches and exceeds levels once considered impossible, the inadequacies of electricity market structures designed for conventional generation have become increasingly apparent. The imperative to redesign these markets while maintaining reliability and affordability represents a formidable challenge for policymakers, regulators, and industry stakeholders.

Traditional electricity markets were conceived during an era when generation assets consisted primarily of large, centralized thermal power plants with predictable costs and controllable output. These markets typically operate through sequential auctions where generators submit bids indicating the price at which they are willing to supply electricity, and a market clearing price is established at the point where supply meets demand. This merit order dispatch system naturally favors generators with lower marginal costs – historically hydroelectric facilities first, followed by nuclear, coal, and finally natural gas plants during peak demand periods.

The introduction of renewable energy fundamentally disrupts this traditional merit order. Wind and solar installations have essentially zero marginal cost since they require no fuel once operational. When abundant renewable generation is available, these sources bid into markets at or near zero, displacing higher-cost conventional generators and depressing wholesale electricity prices. This merit order effect benefits consumers through lower electricity costs but creates what economists term the missing money problem – insufficient market revenues to maintain adequate generation capacity for periods when renewable output is low.

This phenomenon has precipitated a vigorous academic and policy debate regarding the appropriate market architecture for renewable-dominated systems. The energy-only market approach, prevalent in regions like Texas, relies solely on price signals during scarcity periods to incentivize investment in generation capacity. Proponents argue this provides economically efficient outcomes, with prices rising to very high levels during supply shortages, thereby rewarding generators that maintain capacity for these critical hours. Critics contend this approach creates price volatility that discourages investment and fails to provide adequate long-term revenue certainty for either conventional or renewable generators.

Capacity markets, implemented in many European countries and the eastern United States, attempt to address this challenge by creating separate payments for generation capacity itself, independent of actual electricity production. Generators receive capacity payments simply for being available to produce electricity when needed, providing revenue stability that facilitates investment in new facilities. However, designing capacity markets that appropriately value different types of generation presents significant challenges. Should a solar farm that only produces during daylight hours receive the same capacity payment as a natural gas plant capable of generating electricity at any time? How should energy storage systems be valued in capacity markets given their ability to both consume and produce electricity?

The concept of flexibility has emerged as perhaps the most critical attribute in renewable-heavy systems, yet market mechanisms to appropriately value and procure flexibility remain underdeveloped. Flexibility encompasses multiple dimensions including ramping capability (how quickly generation can increase or decrease), minimum stable generation level (how low a plant can reduce output while remaining operational), and start-up time (how quickly an offline plant can begin producing electricity). Traditional market designs rarely explicitly reward these characteristics, leading to the retirement of flexible natural gas plants that provide essential balancing services but struggle to compete economically against renewable generation in energy markets.

Some jurisdictions have begun implementing scarcity pricing mechanisms designed to allow electricity prices to rise to much higher levels during shortage conditions, theoretically providing adequate revenue for flexible resources that operate infrequently. Ireland’s I-SEM (Integrated Single Electricity Market) incorporates sophisticated scarcity pricing that considers not just current supply-demand balance but forward-looking reliability metrics. However, political resistance to allowing extremely high electricity prices during shortages remains strong, as evidenced by the regulatory and public backlash following high prices during the 2021 Texas winter storm.

Renewable energy subsidies represent another contentious policy dimension. Feed-in tariffs (FITs), which guarantee renewable generators a fixed price for their electricity over extended periods, successfully catalyzed initial renewable deployment in countries like Germany and Spain. These policies provided the long-term revenue certainty needed to secure financing for capital-intensive renewable projects when the technologies were still relatively expensive. However, guaranteed prices divorced from market conditions can lead to economic inefficiencies and subsidy costs that become politically unsustainable as renewable capacity expands.

Many jurisdictions have transitioned from feed-in tariffs to competitive auctions where renewable developers bid for contracts, with awards going to the lowest-cost proposals. This approach harnesses competitive dynamics to drive down costs while still providing revenue certainty to successful bidders. Recent renewable energy auctions in countries such as Portugal, Saudi Arabia, and Chile have yielded remarkably low bid prices, with solar projects clearing below $0.02 per kilowatt-hour – costs once considered inconceivable. Nevertheless, concerns persist about whether aggressive bidding may lead to project cancellations or financial distress among developers who underestimated costs or overestimated performance.

The carbon pricing debate intersects critically with renewable energy integration policy. Economic theory suggests that internalizing the externalities of carbon emissions through either carbon taxes or cap-and-trade systems would level the playing field between conventional and renewable generation without requiring technology-specific subsidies. The European Union’s Emissions Trading System (ETS), the world’s largest carbon market, has seen allowance prices rise substantially in recent years, improving the economic competitiveness of renewable energy. However, carbon pricing mechanisms face formidable political obstacles in many jurisdictions, and questions remain about the price levels necessary to drive sufficient renewable deployment to meet climate objectives.

Network charges and grid connection policies create additional layers of regulatory complexity with significant implications for renewable integration. The traditional approach of charging generators for grid connection based on their maximum capacity penalizes intermittent renewable sources that rarely operate at peak output. Alternative approaches such as nodal pricing (where electricity prices vary by location based on local supply-demand balance and transmission constraints) can provide more efficient signals for renewable siting decisions but add complexity that some stakeholders find problematic.

The temporal mismatch between renewable generation patterns and electricity demand creates opportunities for price arbitrage through energy storage, yet regulatory uncertainty regarding how storage assets should be classified and compensated has hindered deployment in some markets. Should battery systems be treated as generation assets, transmission assets, or an entirely new category? Can a single storage facility participate in multiple markets simultaneously, providing both energy arbitrage and frequency regulation services? Different jurisdictions have arrived at divergent answers to these questions, creating a fragmented regulatory landscape that complicates investment decisions for storage developers.

Distributed energy resources present additional regulatory challenges that blur traditional boundaries between electricity producers and consumers. Net metering policies, which credit rooftop solar owners for excess electricity fed into the grid at the same retail rate they pay for consumed electricity, have proven controversial. Utilities argue that net metering allows solar adopters to avoid paying for grid infrastructure costs, effectively shifting these costs to non-solar customers in a regressive manner. Solar advocates counter that distributed generation provides grid support services and reduces the need for transmission infrastructure investment, benefits that net metering compensation fails to fully capture.

The concept of sector coupling – integrating electricity systems with other energy-consuming sectors such as transportation, heating, and industrial processes – has gained prominence as a strategy for accommodating high renewable penetration. Vehicle-to-grid (V2G) technology enables electric vehicles to serve as distributed storage resources, charging when renewable generation is abundant and potentially discharging to support the grid during shortage periods. Power-to-X technologies that convert electricity into other energy carriers (hydrogen, synthetic fuels, heat) offer additional flexibility mechanisms. However, realizing these opportunities requires regulatory frameworks that facilitate cross-sector coordination and appropriately compensate participants for the grid services they provide.

International experience provides valuable, albeit sometimes cautionary, lessons. Denmark’s electricity system regularly operates with wind providing 100% or more of demand (with excess exported to neighboring countries), demonstrating technical feasibility but relying on extensive interconnections with hydroelectric-rich Norway and Sweden to provide balancing resources. Germany’s Energiewende (energy transition) has successfully expanded renewable capacity to the point where renewables provide more than 40% of electricity generation, yet challenges including grid congestion, curtailment of renewable generation during excess supply periods, and rising consumer electricity costs highlight ongoing implementation difficulties.

California’s experience offers insights into both achievements and remaining challenges. The state regularly sets records for renewable energy penetration, with solar providing up to 60% of electricity during spring afternoons. However, the dramatic evening ramp when solar output plummets as the sun sets requires rapid deployment of natural gas generation or imported electricity, creating the now-famous “duck curve” load pattern that symbolizes renewable integration challenges. California has responded through aggressive energy storage mandates and increasingly sophisticated market interventions, yet the optimal long-term market structure remains contested.

The transition toward market designs appropriate for renewable-dominated systems involves fundamental tensions between economic efficiency, reliability, environmental objectives, and political feasibility. No jurisdiction has yet developed a definitive model that fully resolves these tensions, suggesting that market evolution will remain an ongoing process of experimentation, evaluation, and adjustment. What appears increasingly clear is that the assumptions underlying traditional electricity market designs – dispatchable generation with predictable costs and centralized production – no longer align with the emerging reality of distributed, weather-dependent renewable energy systems. Bridging this gap requires not just incremental policy adjustments but potentially a fundamental reconceptualization of how electricity markets function and what attributes they should value and reward.

Questions 27-40

Questions 27-31: Multiple Choice

Choose the correct letter, A, B, C or D.

27. According to the passage, traditional electricity markets were designed for
A. renewable energy sources
B. distributed generation systems
C. large centralized thermal power plants
D. unpredictable energy outputs

28. The “missing money problem” refers to
A. insufficient revenue to maintain adequate generation capacity
B. consumers paying too much for electricity
C. renewable energy being too expensive
D. governments running budget deficits

29. Energy-only markets rely on
A. government subsidies for generators
B. price signals during scarcity periods
C. fixed payments to all power plants
D. international electricity imports

30. The passage suggests that flexibility in power systems
A. is not important for renewable integration
B. is adequately rewarded in current markets
C. remains undervalued in most market designs
D. only matters for solar energy

31. Competitive auctions for renewable energy have resulted in
A. higher electricity prices for consumers
B. remarkably low bid prices
C. project cancellations in all countries
D. increased government costs

Questions 32-36: Matching Sentence Endings

Complete each sentence with the correct ending, A-I, below.

32. Wind and solar installations have essentially zero marginal cost because

33. Capacity markets attempt to address revenue instability by

34. Feed-in tariffs successfully catalyzed renewable deployment by

35. Net metering policies have become controversial because

36. The duck curve in California symbolizes

A. they may shift infrastructure costs to non-solar customers
B. they require no fuel once operational
C. the rapid evening ramp when solar output drops suddenly
D. providing separate payments for generation capacity availability
E. they produce electricity intermittently
F. guaranteeing renewable generators fixed long-term prices
G. they operate only during specific hours
H. using subsidies to reduce consumer costs
I. the high cost of renewable energy integration

Questions 37-40: Short-answer Questions

Answer the questions below.

Choose NO MORE THAN THREE WORDS from the passage for each answer.

37. What type of pricing mechanism in Ireland considers forward-looking reliability metrics alongside current supply-demand balance?

38. What is the world’s largest carbon market called?

39. What term describes the integration of electricity systems with transportation, heating, and industrial sectors?

40. Which two countries, rich in hydroelectric resources, provide balancing resources to Denmark?

Mô hình thị trường điện năng lượng tái tạo với cơ chế đấu giá và định giá linh hoạt

3. Answer Keys – Đáp Án

PASSAGE 1: Questions 1-13

1. B
2. C
3. B
4. C
5. A
6. TRUE
7. FALSE
8. NOT GIVEN
9. NOT GIVEN
10. zero emissions
11. weather
12. unidirectional
13. Demand response

PASSAGE 2: Questions 14-26

14. NO
15. YES
16. NO
17. YES
18. NO
19. C
20. E
21. A
22. G
23. F
24. geographic mismatch
25. ramp rate limitation
26. negative electricity prices

PASSAGE 3: Questions 27-40

27. C
28. A
29. B
30. C
31. B
32. B
33. D
34. F
35. A
36. C
37. scarcity pricing
38. Emissions Trading System / ETS
39. sector coupling
40. Norway and Sweden

4. Giải Thích Đáp Án Chi Tiết

Passage 1 – Giải Thích

Câu 1: B

• Dạng câu hỏi: Multiple Choice
• Từ khóa: solar photovoltaic costs, since 2010
• Vị trí trong bài: Đoạn 2, dòng 1-2
• Giải thích: Bài đọc nói rõ “Solar photovoltaic technology… has seen costs plummet by more than 90% since 2010.” Từ “plummet” được paraphrase thành “decreased” trong đáp án B. Đáp án này chính xác phản ánh thông tin về mức giảm 90% chi phí.

Câu 2: C

• Dạng câu hỏi: Multiple Choice
• Từ khóa: modern wind turbines, described
• Vị trí trong bài: Đoạn 3, dòng 2-3
• Giải thích: Passage nêu trực tiếp “Modern wind turbines stand as tall as 200 meters”, khớp chính xác với đáp án C. Các đáp án khác không được đề cập hoặc mâu thuẫn với thông tin trong bài.

Câu 3: B

• Dạng câu hỏi: Multiple Choice
• Từ khóa: dual-use farming, allows
• Vị trí trong bài: Đoạn 4, dòng 6-7
• Giải thích: Bài viết giải thích “The land beneath wind turbines can often continue to be used for agriculture, a practice known as dual-use farming”. Đây chính xác là đáp án B – hoạt động nông nghiệp có thể tiếp tục dưới chân tuabin.

Câu 4: C

• Dạng câu hỏi: Multiple Choice
• Từ khóa: main difference, renewable, conventional power plants
• Vị trí trong bài: Đoạn 5, dòng 3-5
• Giải thích: Đoạn văn so sánh “This variability stands in stark contrast to conventional power plants, which can produce steady, predictable amounts of electricity 24 hours a day.” Sự khác biệt chính là về tính dự đoán được (predictability) của sản lượng điện, đáp án C.

Câu 5: A

• Dạng câu hỏi: Multiple Choice
• Từ khóa: grid operators’ jobs, more complex
• Vị trí trong bài: Đoạn 6, dòng 4-6
• Giải thích: Bài đọc giải thích rằng hệ thống năng lượng tái tạo tạo ra “multidirectional flow” so với “unidirectional flow” truyền thống, khiến công việc trở nên phức tạp hơn. Đây chính xác là đáp án A.

Câu 6: TRUE

• Dạng câu hỏi: True/False/Not Given
• Từ khóa: rooftop solar installations, sell excess electricity
• Vị trí trong bài: Đoạn 2, dòng 6-8
• Giải thích: Passage nêu rõ “allowing individual property owners to generate their own electricity and sometimes even sell excess power back to the grid”, khớp hoàn toàn với phát biểu.

Câu 7: FALSE

• Dạng câu hỏi: True/False/Not Given
• Từ khóa: offshore wind farms, less productive
• Vị trí trong bài: Đoạn 3, dòng 5-6
• Giải thích: Bài viết nói “Offshore wind farms, positioned in coastal waters where winds blow stronger and more consistently than on land” – điều này cho thấy offshore wind farms thực ra hiệu quả hơn, mâu thuẫn với phát biểu.

Câu 8: NOT GIVEN

• Dạng câu hỏi: True/False/Not Given
• Từ khóa: single wind turbine, eliminate, 40,000 trees
• Vị trí trong bài: Đoạn 4, dòng 4-5
• Giải thích: Bài viết nói “equivalent to planting roughly 40,000 trees” về việc giảm CO2, không phải “eliminate the need for” cây. Thông tin không khớp với ý nghĩa trong câu hỏi.

Câu 9: NOT GIVEN

• Dạng câu hỏi: True/False/Not Given
• Từ khóa: Hornsdale Power Reserve, most expensive
• Vị trí trong bài: Đoạn 7, dòng 3-6
• Giải thích: Passage chỉ nói đây là “world’s largest lithium-ion battery”, không đề cập đến chi phí. Không có thông tin để xác định phát biểu đúng hay sai.

Câu 10: zero emissions

• Dạng câu hỏi: Sentence Completion
• Từ khóa: solar panels, wind turbines, produce, operation
• Vị trí trong bài: Đoạn 4, dòng 1-2
• Giải thích: Câu trong bài: “solar panels and wind turbines produce zero emissions during operation” – cụm “zero emissions” chính xác điền vào chỗ trống.

Câu 11: weather

• Dạng câu hỏi: Sentence Completion
• Từ khóa: intermittency, renewable energy production, dependent
• Vị trí trong bài: Đoạn 5, dòng 1-3
• Giải thích: Bài viết giải thích intermittency là “solar panels only generate electricity when the sun shines, and wind turbines only turn when the wind blows” – cả hai đều là điều kiện thời tiết (weather conditions).

Câu 12: unidirectional

• Dạng câu hỏi: Sentence Completion
• Từ khóa: traditional grids, designed, electricity flow
• Vị trí trong bài: Đoạn 6, dòng 2-3
• Giải thích: Passage nêu rõ “Traditional grids were designed for a unidirectional flow of electricity” – từ “unidirectional” là đáp án chính xác.

Câu 13: Demand response

• Dạng câu hỏi: Sentence Completion
• Từ khóa: programs, encourage consumers, adjust electricity usage
• Vị trí trong bài: Đoạn 9, dòng 1-2
• Giải thích: Bài viết giới thiệu “Demand response programs represent yet another strategy. These initiatives encourage or incentivize consumers to adjust their electricity usage” – “Demand response” là tên chính xác của loại chương trình này.

Passage 2 – Giải Thích

Câu 14: NO

• Dạng câu hỏi: Yes/No/Not Given
• Từ khóa: instantaneous balance, primarily economic consideration
• Vị trí trong bài: Đoạn 2, dòng 1-4
• Giải thích: Bài viết nêu rõ “This balance is not merely a matter of convenience but a physical necessity” – đây là yêu cầu vật lý, không phải chủ yếu về kinh tế. Phát biểu mâu thuẫn với quan điểm của tác giả.

Câu 15: YES

• Dạng câu hỏi: Yes/No/Not Given
• Từ khóa: traditional power plants, grid stability, mechanical inertia
• Vị trí trong bài: Đoạn 2, dòng 7-9
• Giải thích: Passage khẳng định “This mechanical inertia inherent in spinning turbines provides crucial grid stability” – khớp hoàn toàn với phát biểu.

Câu 16: NO

• Dạng câu hỏi: Yes/No/Not Given
• Từ khóa: system operators, confident, renewables exceed 50%
• Vị trí trong bài: Đoạn 3, dòng 5-7
• Giải thích: Bài viết nói “System operators express concern about maintaining grid stability when renewables comprise more than 50%” – họ lo lắng (concern), không phải tự tin (confident). Mâu thuẫn với phát biểu.

Câu 17: YES

• Dạng câu hỏi: Yes/No/Not Given
• Từ khóa: HVDC transmission, more efficient, long distances
• Vị trí trong bài: Đoạn 5, dòng 1-3
• Giải thích: Passage nêu “HVDC experiences lower electrical losses over extended distances” so với AC – điều này chứng tỏ nó hiệu quả hơn cho khoảng cách dài. Khớp với phát biểu.

Câu 18: NO

• Dạng câu hỏi: Yes/No/Not Given
• Từ khóa: machine learning algorithms, completely solved, forecasting
• Vị trí trong bài: Đoạn 6, dòng 4-6
• Giải thích: Bài viết nói “show promise in improving forecast accuracy, but unexpected weather events can still cause significant deviations” – chưa giải quyết hoàn toàn vấn đề. Mâu thuẫn với “completely solved”.

Câu 19: C

• Dạng câu hỏi: Matching Information
• Từ khóa: ramp up faster than coal, 10-30 minutes
• Vị trí trong bài: Đoạn 7, dòng 3-5
• Giải thích: “Combined-cycle gas turbines can ramp somewhat faster but still need 10-30 minutes for substantial changes” – chính xác mô tả combined-cycle gas turbines (C).

Câu 20: E

• Dạng câu hỏi: Matching Information
• Từ khóa: aggregate distributed energy resources, software platforms
• Vị trí trong bài: Đoạn 11, dòng 3-4
• Giải thích: “Virtual power plants that aggregate DERs through software platforms” – mô tả chính xác virtual power plants (E).

Câu 21: A

• Dạng câu hỏi: Matching Information
• Từ khóa: dominate current installations, not cost-effective, long-duration storage
• Vị trí trong bài: Đoạn 9, dòng 1-3
• Giải thích: “The lithium-ion batteries that dominate current installations excel at providing short-duration services… but become economically prohibitive for storing energy across multiple hours” – đúng với lithium-ion batteries (A).

Câu 22: G

• Dạng câu hỏi: Matching Information
• Từ khóa: uses renewable electricity, storable chemical energy
• Vị trí trong bài: Đoạn 12, dòng 2-3
• Giải thích: “Green hydrogen production, which uses excess renewable electricity to split water molecules, offers a means of converting surplus generation into storable chemical energy” – mô tả green hydrogen production (G).

Câu 23: F

• Dạng câu hỏi: Matching Information
• Từ khóa: power electronics, replicate stabilizing effects
• Vị trí trong bài: Đoạn 12, dòng 1-2
• Giải thích: “Synthetic inertia – using power electronics to simulate the stabilizing effects of mechanical inertia” – mô tả synthetic inertia (F).

Câu 24: geographic mismatch

• Dạng câu hỏi: Summary Completion
• Từ khóa: geographic distribution, between generation locations, demand centers
• Vị trí trong bài: Đoạn 4, dòng 5-7
• Giải thích: “This geographic mismatch necessitates significant investment in transmission infrastructure” – cụm “geographic mismatch” chính xác điền vào chỗ trống.

Câu 25: ramp rate limitation

• Dạng câu hỏi: Summary Completion
• Từ khóa: renewable output decreases, conventional plants, how quickly compensate
• Vị trí trong bài: Đoạn 7, dòng 1-2
• Giải thích: “The ramp rate limitation of conventional power plants further complicates renewable integration” – “ramp rate limitation” là thuật ngữ chính xác mô tả hạn chế này.

Câu 26: negative electricity prices

• Dạng câu hỏi: Summary Completion
• Từ khóa: excess generation periods, generators pay consumers
• Vị trí trong bài: Đoạn 10, dòng 1-3
• Giải thích: “The phenomenon of negative electricity prices… generators essentially pay consumers to take electricity” – “negative electricity prices” là khái niệm chính xác.

Passage 3 – Giải Thích

Câu 27: C

• Dạng câu hỏi: Multiple Choice
• Từ khóa: traditional electricity markets, designed for
• Vị trí trong bài: Đoạn 2, dòng 1-2
• Giải thích: “Traditional electricity markets were conceived during an era when generation assets consisted primarily of large, centralized thermal power plants” – khớp chính xác với đáp án C.

Câu 28: A

• Dạng câu hỏi: Multiple Choice
• Từ khóa: missing money problem
• Vị trí trong bài: Đoạn 3, dòng 6-8
• Giải thích: Bài viết giải thích “the missing money problem – insufficient market revenues to maintain adequate generation capacity for periods when renewable output is low” – đáp án A phản ánh chính xác định nghĩa này.

Câu 29: B

• Dạng câu hỏi: Multiple Choice
• Từ khóa: energy-only markets, rely on
• Vị trí trong bài: Đoạn 4, dòng 2-4
• Giải thích: “The energy-only market approach… relies solely on price signals during scarcity periods to incentivize investment” – đáp án B chính xác.

Câu 30: C

• Dạng câu hỏi: Multiple Choice
• Từ khóa: flexibility, power systems
• Vị trí trong bài: Đoạn 6, dòng 1-3
• Giải thích: “The concept of flexibility has emerged as perhaps the most critical attribute in renewable-heavy systems, yet market mechanisms to appropriately value and procure flexibility remain underdeveloped” – cho thấy flexibility vẫn chưa được đánh giá đúng mức (undervalued), đáp án C.

Câu 31: B

• Dạng câu hỏi: Multiple Choice
• Từ khóa: competitive auctions, resulted in
• Vị trí trong bài: Đoạn 8, dòng 4-6
• Giải thích: “Recent renewable energy auctions… have yielded remarkably low bid prices, with solar projects clearing below $0.02 per kilowatt-hour” – đáp án B chính xác.

Câu 32: B

• Dạng câu hỏi: Matching Sentence Endings
• Từ khóa: wind and solar, zero marginal cost, because
• Vị trí trong bài: Đoạn 3, dòng 1-2
• Giải thích: “Wind and solar installations have essentially zero marginal cost since they require no fuel once operational” – ending B khớp hoàn hảo với giải thích này.

Câu 33: D

• Dạng câu hỏi: Matching Sentence Endings
• Từ khóa: capacity markets, attempt to address, by
• Vị trí trong bài: Đoạn 5, dòng 1-3
• Giải thích: “Capacity markets… attempt to address this challenge by creating separate payments for generation capacity itself” – ending D mô tả chính xác cơ chế này.

Câu 34: F

• Dạng câu hỏi: Matching Sentence Endings
• Từ khóa: feed-in tariffs, catalyzed deployment, by
• Vị trí trong bài: Đoạn 7, dòng 2-5
• Giải thích: “Feed-in tariffs, which guarantee renewable generators a fixed price for their electricity over extended periods, successfully catalyzed initial renewable deployment” – ending F khớp với “guarantee… fixed price”.

Câu 35: A

• Dạng câu hỏi: Matching Sentence Endings
• Từ khóa: net metering policies, controversial, because
• Vị trí trong bài: Đoạn 12, dòng 2-4
• Giải thích: “Utilities argue that net metering allows solar adopters to avoid paying for grid infrastructure costs, effectively shifting these costs to non-solar customers” – ending A phản ánh chính xác lập luận gây tranh cãi này.

Câu 36: C

• Dạng câu hỏi: Matching Sentence Endings
• Từ khóa: duck curve, California, symbolizes
• Vị trí trong bài: Đoạn 15, dòng 2-4
• Giải thích: “However, the dramatic evening ramp when solar output plummets as the sun sets… creating the now-famous ‘duck curve'” – ending C mô tả chính xác ý nghĩa của duck curve.

Câu 37: scarcity pricing

• Dạng câu hỏi: Short-answer Questions
• Từ khóa: Ireland, considers forward-looking reliability metrics
• Vị trí trong bài: Đoạn 6, dòng 7-9
• Giải thích: “Ireland’s I-SEM (Integrated Single Electricity Market) incorporates sophisticated scarcity pricing that considers not just current supply-demand balance but forward-looking reliability metrics” – đáp án là “scarcity pricing”.

Câu 38: Emissions Trading System / ETS

• Dạng câu hỏi: Short-answer Questions
• Từ khóa: world’s largest carbon market
• Vị trí trong bài: Đoạn 9, dòng 4-5
• Giải thích: “The European Union’s Emissions Trading System (ETS), the world’s largest carbon market” – có thể trả lời bằng tên đầy đủ hoặc viết tắt.

Câu 39: sector coupling

• Dạng câu hỏi: Short-answer Questions
• Từ khóa: integration, electricity systems, transportation, heating, industrial
• Vị trí trong bài: Đoạn 13, dòng 1-2
• Giải thích: “The concept of sector coupling – integrating electricity systems with other energy-consuming sectors such as transportation, heating, and industrial processes” – thuật ngữ là “sector coupling”.

Câu 40: Norway and Sweden

• Dạng câu hỏi: Short-answer Questions
• Từ khóa: countries, hydroelectric resources, balancing resources, Denmark
• Vị trí trong bài: Đoạn 14, dòng 1-3
• Giải thích: “Denmark’s electricity system… relying on extensive interconnections with hydroelectric-rich Norway and Sweden to provide balancing resources” – đáp án là “Norway and Sweden”.

5. Từ Vựng Quan Trọng Theo Passage

Passage 1 – Essential Vocabulary

Từ vựng	Loại từ	Phiên âm	Nghĩa tiếng Việt	Ví dụ từ bài	Collocation
renewable energy	n	/rɪˈnjuːəbl ˈenədʒi/	năng lượng tái tạo	renewable energy sources have experienced remarkable growth	renewable energy sector, renewable energy transition
fossil fuels	n	/ˈfɒsl fjuːəlz/	nhiên liệu hóa thạch	most prominent alternatives to traditional fossil fuels	burn fossil fuels, fossil fuel dependency
photovoltaic	adj	/ˌfəʊtəʊvɒlˈteɪɪk/	quang điện, quang-vôn	Solar photovoltaic technology converts sunlight	photovoltaic cells, photovoltaic panels
economically competitive	adj phrase	/ˌiːkəˈnɒmɪkli kəmˈpetətɪv/	cạnh tranh về mặt kinh tế	made solar power economically competitive with coal	economically competitive industry
kinetic energy	n	/kɪˈnetɪk ˈenədʒi/	động năng	harness the kinetic energy of moving air	kinetic energy conversion
intermittency	n	/ˌɪntəˈmɪtənsi/	tính gián đoạn	The most significant issue is intermittency	intermittency problem, address intermittency
variability	n	/ˌveəriəˈbɪləti/	tính biến đổi	This variability stands in stark contrast	price variability, output variability
grid operators	n	/ɡrɪd ˈɒpəreɪtəz/	người vận hành lưới điện	Grid operators face increasingly complex challenges	experienced grid operators
unidirectional flow	n phrase	/ˌjuːnɪdaɪˈrekʃənl fləʊ/	dòng chảy một chiều	designed for a unidirectional flow of electricity	unidirectional flow pattern
decentralized	adj	/diːˈsentrəlaɪzd/	phi tập trung	Renewable energy systems are often decentralized	decentralized system, decentralized network
lithium-ion batteries	n	/ˈlɪθiəm ˈaɪɒn ˈbætəriz/	pin lithium-ion	Battery systems, particularly lithium-ion batteries	lithium-ion battery technology
transmission lines	n	/trænzˈmɪʃn laɪnz/	đường dây truyền tải	Long-distance transmission lines can transport electricity	high-voltage transmission lines

Passage 2 – Essential Vocabulary

Từ vựng	Loại từ	Phiên âm	Nghĩa tiếng Việt	Ví dụ từ bài	Collocation
intricate interactions	n phrase	/ˈɪntrɪkət ˌɪntərˈækʃnz/	tương tác phức tạp	intricate interactions between physics, economics, and policy	intricate interactions between systems
instantaneous balance	n phrase	/ˌɪnstənˈteɪniəs ˈbæləns/	cân bằng tức thời	principle of instantaneous balance	maintain instantaneous balance
cascading failures	n phrase	/kæsˈkeɪdɪŋ ˈfeɪljəz/	những sự cố dây chuyền	trigger cascading failures that lead to blackouts	prevent cascading failures
mechanical inertia	n phrase	/məˈkænɪkl ɪˈnɜːʃə/	quán tính cơ học	This mechanical inertia provides crucial grid stability	mechanical inertia effect
power electronics	n	/ˈpaʊər ɪlekˈtrɒnɪks/	điện tử công suất	connect to the grid through power electronics	advanced power electronics
inverters	n	/ɪnˈvɜːtəz/	bộ nghịch lưu	power electronics called inverters	solar inverters, grid-tied inverters
spatial distribution	n phrase	/ˈspeɪʃl ˌdɪstrɪˈbjuːʃn/	phân bố không gian	The spatial distribution of renewable resources	spatial distribution pattern
geographic mismatch	n phrase	/ˌdʒiːəˈɡræfɪk ˈmɪsmætʃ/	sự không tương xứng về địa lý	This geographic mismatch necessitates investment	geographic mismatch between supply and demand
asynchronous grids	n phrase	/eɪˈsɪŋkrənəs ɡrɪdz/	lưới điện không đồng bộ	can connect asynchronous grids operating at different frequencies	interconnect asynchronous grids
forecasting	n	/ˈfɔːkɑːstɪŋ/	dự báo	Forecasting renewable energy production presents challenges	weather forecasting, accurate forecasting
ramp rate limitation	n phrase	/ræmp reɪt ˌlɪmɪˈteɪʃn/	hạn chế tốc độ tăng giảm	The ramp rate limitation of conventional power plants	ramp rate limitation problem
ancillary services	n phrase	/ænˈsɪləri ˈsɜːvɪsɪz/	dịch vụ bổ trợ	Ancillary services become increasingly valuable	provide ancillary services
frequency regulation	n phrase	/ˈfriːkwənsi ˌreɡjuˈleɪʃn/	điều chỉnh tần số	services include frequency regulation	frequency regulation service
round-trip efficiency	n phrase	/raʊnd trɪp ɪˈfɪʃnsi/	hiệu suất khứ hồi	lower round-trip efficiency	improve round-trip efficiency
distributed energy resources	n phrase	/dɪˈstrɪbjuːtɪd ˈenədʒi rɪˈsɔːsɪz/	nguồn năng lượng phân tán	Distributed energy resources add opportunities	manage distributed energy resources

Passage 3 – Essential Vocabulary

Từ vựng	Loại từ	Phiên âm	Nghĩa tiếng Việt	Ví dụ từ bài	Collocation
inadequacies	n	/ˌɪnˈædɪkwəsiz/	những điểm không đầy đủ	the inadequacies of electricity market structures	address inadequacies
imperative	n	/ɪmˈperətɪv/	nhu cầu cấp bách	The imperative to redesign these markets	strategic imperative, economic imperative
sequential auctions	n phrase	/sɪˈkwenʃl ˈɔːkʃnz/	đấu giá tuần tự	operate through sequential auctions	conduct sequential auctions
market clearing price	n phrase	/ˈmɑːkɪt ˈklɪərɪŋ praɪs/	giá cân bằng thị trường	a market clearing price is established	determine market clearing price
merit order dispatch	n phrase	/ˈmerɪt ˈɔːdə dɪˈspætʃ/	phân phối theo thứ tự ưu tiên	This merit order dispatch system	merit order dispatch mechanism
zero marginal cost	n phrase	/ˈzɪərəʊ ˈmɑːdʒɪnl kɒst/	chi phí biên bằng không	have essentially zero marginal cost	zero marginal cost production
missing money problem	n phrase	/ˈmɪsɪŋ ˈmʌni ˈprɒbləm/	vấn đề thiếu hụt doanh thu	creates what economists term the missing money problem	solve the missing money problem
price volatility	n phrase	/praɪs ˌvɒləˈtɪləti/	biến động giá	creates price volatility that discourages investment	reduce price volatility
capacity markets	n phrase	/kəˈpæsəti ˈmɑːkɪts/	thị trường công suất	Capacity markets attempt to address this challenge	participate in capacity markets
ramping capability	n phrase	/ˈræmpɪŋ ˌkeɪpəˈbɪləti/	khả năng tăng giảm công suất	Flexibility encompasses ramping capability	improve ramping capability
scarcity pricing	n phrase	/ˈskeəsəti ˈpraɪsɪŋ/	định giá khan hiếm	implementing scarcity pricing mechanisms	scarcity pricing mechanism
feed-in tariffs	n phrase	/fiːd ɪn ˈtærɪfs/	biểu giá đầu vào	Feed-in tariffs successfully catalyzed deployment	introduce feed-in tariffs
externalities	n	/ˌekstɜːˈnæləti/	ngoại tác	internalizing the externalities of carbon emissions	environmental externalities
cap-and-trade systems	n phrase	/kæp ənd treɪd ˈsɪstəmz/	hệ thống hạn mức và mua bán	either carbon taxes or cap-and-trade systems	implement cap-and-trade systems
nodal pricing	n phrase	/ˈnəʊdl ˈpraɪsɪŋ/	định giá theo nút	Alternative approaches such as nodal pricing	nodal pricing system
temporal mismatch	n phrase	/ˈtempərəl ˈmɪsmætʃ/	sự không tương xứng về thời gian	The temporal mismatch between generation patterns	temporal mismatch problem
price arbitrage	n phrase	/praɪs ˈɑːbɪtrɑːʒ/	chênh lệch giá	creates opportunities for price arbitrage	exploit price arbitrage
sector coupling	n phrase	/ˈsektə ˈkʌplɪŋ/	liên kết liên ngành	The concept of sector coupling has gained prominence	promote sector coupling

Kết Bài

Chủ đề tích hợp năng lượng tái tạo vào lưới điện quốc gia không chỉ là một nội dung thường xuyên xuất hiện trong IELTS Reading mà còn phản ánh những thách thức thực tế đang được các quốc gia trên toàn cầu đối mặt. Qua bộ đề thi này, bạn đã được trải nghiệm ba passages với độ khó tăng dần, từ những khái niệm cơ bản về năng lượng mặt trời và gió, đến các thách thức kỹ thuật phức tạp trong quản lý lưới điện, và cuối cùng là những vấn đề chính sách và cơ chế thị trường tinh vi.

Ba passages đã cung cấp cho bạn 40 câu hỏi đa dạng với đầy đủ các dạng bài xuất hiện trong kỳ thi IELTS Reading thực tế. Từ Multiple Choice, True/False/Not Given, Matching Information đến Summary Completion và Short-answer Questions – mỗi dạng đều được thiết kế cẩn thận để phản ánh chuẩn mực của Cambridge IELTS và các đề thi chính thức.

Phần đáp án chi tiết kèm theo giải thích không chỉ giúp bạn tự đánh giá kết quả mà còn hiểu rõ cách xác định từ khóa, paraphrase thông tin và áp dụng các chiến lược làm bài hiệu quả. Đây là kỹ năng quan trọng giúp bạn tiết kiệm thời gian và nâng cao độ chính xác trong kỳ thi thực tế.

Bảng từ vựng được tổng hợp theo từng passage cung cấp cho bạn hơn 40 từ và cụm từ học thuật quan trọng, hoàn chỉnh với phiên âm, nghĩa tiếng Việt, ví dụ sử dụng và collocations. Những từ vựng này không chỉ hữu ích cho phần Reading mà còn có thể áp dụng trong Writing và Speaking, đặc biệt với các chủ đề về môi trường, công nghệ và phát triển bền vững.

Hãy sử dụng bộ đề này như một công cụ luyện tập thực chiến, tuân thủ thời gian quy định cho từng passage để tạo áp lực tương tự như kỳ thi thật. Sau khi hoàn thành, dành thời gian phân tích kỹ những câu làm sai để hiểu rõ nguyên nhân và cải thiện trong những lần luyện tập tiếp theo. Với sự luyện tập đều đặn và phương pháp đúng đắn, bạn hoàn toàn có thể đạt được band điểm mục tiêu của mình.