IELTS Reading: Green Energy for Sustainable Farming – Đề thi mẫu có đáp án chi tiết

Trong bối cảnh biến đổi khí hậu và nhu cầu phát triển bền vững ngày càng cấp thiết, chủ đề “Green Energy For Sustainable Farming” (Năng lượng xanh cho nông nghiệp bền vững) đã trở thành một trong những đề tài phổ biến trong kỳ thi IELTS Reading. Chủ đề này thường xuyên xuất hiện trong các đề thi IELTS thực tế với tần suất khoảng 15-20% trong các bài thi liên quan đến môi trường và khoa học.

Bài viết này cung cấp cho bạn một bộ đề thi IELTS Reading hoàn chỉnh với 3 passages theo đúng chuẩn Cambridge IELTS, bao gồm: Passage 1 – Easy (Band 5.0-6.5) giới thiệu khái niệm cơ bản về năng lượng tái tạo trong nông nghiệp; Passage 2 – Medium (Band 6.0-7.5) phân tích các ứng dụng cụ thể và lợi ích kinh tế; Passage 3 – Hard (Band 7.0-9.0) thảo luận sâu về các thách thức công nghệ và chính sách. Mỗi passage đi kèm với đầy đủ 40 câu hỏi đa dạng dạng, đáp án chi tiết có giải thích rõ ràng, và bảng từ vựng quan trọng giúp bạn nâng cao vốn từ học thuật. Đề thi này phù hợp cho học viên từ band 5.0 trở lên, giúp bạn làm quen với format thi thật và rèn luyện kỹ năng làm bài hiệu quả.

Hướng dẫn làm bài IELTS Reading

Tổng Quan Về IELTS Reading Test

IELTS Reading Test kéo dài 60 phút với 3 passages và tổng cộng 40 câu hỏi. Điểm số được tính dựa trên số câu trả lời đúng, không bị trừ điểm khi sai. Để đạt hiệu quả tối ưu, bạn nên phân bổ thời gian hợp lý:

• Passage 1 (Easy): 15-17 phút – Bài đọc ngắn nhất với từ vựng đơn giản, thông tin rõ ràng
• Passage 2 (Medium): 18-20 phút – Bài đọc có độ phức tạp trung bình, yêu cầu kỹ năng paraphrase
• Passage 3 (Hard): 23-25 phút – Bài đọc dài nhất với nội dung học thuật, từ vựng chuyên ngành

Lưu ý: Dành 2-3 phút cuối để kiểm tra và chuyển đáp án vào answer sheet.

Các Dạng Câu Hỏi Trong Đề Này

Đề thi mẫu này bao gồm 7 dạng câu hỏi phổ biến nhất trong IELTS Reading:

1. Multiple Choice – Chọn đáp án đúng từ các lựa chọn cho sẵn
2. True/False/Not Given – Xác định thông tin đúng, sai hoặc không được nhắc đến
3. Matching Information – Nối thông tin với đoạn văn tương ứng
4. Sentence Completion – Hoàn thành câu với từ trong bài đọc
5. Matching Headings – Chọn tiêu đề phù hợp cho mỗi đoạn
6. Summary Completion – Điền từ vào đoạn tóm tắt
7. Short-answer Questions – Trả lời câu hỏi ngắn với số từ giới hạn

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IELTS Reading Practice Test

PASSAGE 1 – Solar Power Revolution in Modern Agriculture

Độ khó: Easy (Band 5.0-6.5)

Thời gian đề xuất: 15-17 phút

The integration of renewable energy into farming practices has become increasingly important in the 21st century. As traditional farming methods consume significant amounts of fossil fuels for machinery, irrigation, and heating, many farmers worldwide are turning to green energy solutions to reduce costs and environmental impact. Among various renewable options, solar power has emerged as the most accessible and practical choice for agricultural operations.

Solar panels, also known as photovoltaic (PV) systems, convert sunlight directly into electricity. These systems have become dramatically more affordable over the past decade, with prices dropping by approximately 70% since 2010. This cost reduction has made solar technology economically viable for small and medium-sized farms. A typical solar installation can generate enough electricity to power irrigation pumps, lighting systems, and cooling facilities, significantly reducing monthly electricity bills.

One of the most successful applications of solar energy in agriculture is solar-powered irrigation. In many developing countries, farmers previously relied on diesel pumps to draw water from wells and rivers. These pumps were expensive to operate and contributed to air pollution. Modern solar water pumps eliminate fuel costs entirely and require minimal maintenance. In India, for example, over 200,000 solar pumps have been installed since 2014, helping farmers irrigate crops more efficiently while reducing carbon emissions.

Greenhouse farming represents another sector where solar energy proves particularly beneficial. Greenhouses require substantial energy for heating, cooling, and lighting to maintain optimal growing conditions year-round. By installing solar panels on greenhouse roofs or nearby land, farmers can achieve energy independence and even sell excess electricity back to the grid. In the Netherlands, which leads Europe in greenhouse agriculture, many facilities now operate as net-zero energy buildings, producing as much energy as they consume.

The advantages of solar farming extend beyond cost savings. Environmental benefits include reduced greenhouse gas emissions, decreased reliance on fossil fuels, and improved air quality in rural areas. Additionally, solar installations can provide shade for crops and livestock, creating dual-use systems where land serves both energy production and agricultural purposes. This approach, called agrivoltaics, maximizes land efficiency without compromising food production.

Despite these advantages, some challenges remain. The initial investment for solar systems can be substantial, typically ranging from $15,000 to $50,000 depending on farm size and energy needs. Many farmers require loans or government subsidies to afford the upfront costs. Weather dependency is another concern – solar panels generate less electricity on cloudy days and no power at night, necessitating battery storage systems or grid connections for consistent energy supply.

Government policies play a crucial role in promoting solar adoption in agriculture. Many countries now offer financial incentives such as tax credits, grants, and low-interest loans specifically for farmers installing renewable energy systems. In the United States, the Rural Energy for America Program provides grants covering up to 25% of project costs. Similarly, the European Union’s Common Agricultural Policy includes provisions for renewable energy investments on farms.

Looking ahead, technological advancements promise to make solar farming even more attractive. Newer thin-film solar panels are lighter and more flexible than traditional silicon panels, making installation easier on various surfaces. Smart inverters and energy management systems allow farmers to optimize electricity usage automatically, directing power where it’s needed most efficiently. As battery technology improves and becomes more affordable, energy storage will become standard, enabling farms to operate independently of the electrical grid.

The transition to solar-powered agriculture represents more than just an energy shift – it’s a fundamental change in how farming integrates with environmental stewardship. Farmers who adopt these technologies not only reduce operational costs but also contribute to climate change mitigation. As global food demand increases and environmental concerns intensify, the combination of agriculture and renewable energy will become increasingly essential for sustainable food production.

Questions 1-13

Questions 1-5: Multiple Choice

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

1. What is mentioned as the primary reason farmers are adopting solar power?

   • A) Government regulations requiring renewable energy
   • B) Reducing costs and environmental impact
   • C) Improved crop yields
   • D) International pressure

2. According to the passage, solar panel prices have:

   • A) Increased by 70% since 2010
   • B) Remained stable over the past decade
   • C) Decreased by approximately 70% since 2010
   • D) Fluctuated unpredictably

3. In India, how many solar pumps have been installed since 2014?

   • A) Over 100,000
   • B) Approximately 150,000
   • C) More than 200,000
   • D) About 250,000

4. What does “net-zero energy buildings” mean in the context of greenhouses?

   • A) Buildings that consume no energy
   • B) Facilities that produce as much energy as they consume
   • C) Structures with negative energy output
   • D) Buildings with minimal construction costs

5. The initial investment for solar systems typically ranges from:

   • A) $5,000 to $15,000
   • B) $10,000 to $30,000
   • C) $15,000 to $50,000
   • D) $50,000 to $100,000

Questions 6-9: True/False/Not Given

Write TRUE if the statement agrees with the information, FALSE if the statement contradicts the information, or NOT GIVEN if there is no information on this.

6. Solar water pumps require more maintenance than diesel pumps.
7. The Netherlands is a leader in greenhouse agriculture in Europe.
8. Agrivoltaics reduces food production capacity on farms.
9. Most farmers can afford solar installations without financial assistance.

Questions 10-13: Sentence Completion

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

10. Solar panels are also referred to as __ systems.
11. One disadvantage of solar energy is its dependency on __, as panels produce less electricity on cloudy days.
12. The Rural Energy for America Program provides grants covering up to __ of project costs.
13. Newer __ solar panels are lighter and more flexible than traditional panels.

Hệ thống pin mặt trời trên mái nhà kính nông nghiệp tạo năng lượng xanh bền vững

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PASSAGE 2 – Economic and Environmental Benefits of Wind Energy in Farming

Độ khó: Medium (Band 6.0-7.5)

Thời gian đề xuất: 18-20 phút

While solar power dominates discussions about renewable energy in agriculture, wind energy presents equally compelling opportunities for farmers seeking to diversify income streams and reduce carbon footprints. Unlike solar installations, which require significant upfront capital and dedicated space, wind turbines can be erected on agricultural land with minimal disruption to farming activities. This dual-use approach allows farmers to continue growing crops or grazing livestock while simultaneously generating clean electricity.

The economics of farm-based wind energy have evolved considerably over the past two decades. Early wind turbines were inefficient and prone to mechanical failures, making them economically unviable for most agricultural applications. However, contemporary turbines feature advanced aerodynamic designs, durable materials, and sophisticated control systems that maximize energy capture even in variable wind conditions. A single modern wind turbine with a capacity of 2-3 megawatts can generate sufficient electricity to power several hundred homes, creating substantial revenue opportunities for landowners.

Lease arrangements represent the most common business model for agricultural wind energy. In this scenario, energy companies install and maintain turbines on farmland, paying landowners annual lease payments typically ranging from $3,000 to $8,000 per turbine. These payments provide stable, predictable income that isn’t subject to the volatility of commodity prices or weather-related crop failures. For farmers struggling with narrow profit margins, wind lease income can mean the difference between financial sustainability and bankruptcy.

Alternatively, some farmers choose to purchase and operate turbines independently, selling electricity directly to the grid through power purchase agreements (PPAs). This approach requires greater capital investment – a 2-megawatt turbine costs approximately $3-4 million installed – but offers higher long-term returns. Farmers pursuing this strategy often form cooperatives to share costs and expertise, a model particularly successful in Denmark and Germany where community-owned wind farms supply significant portions of regional electricity demand.

The environmental credentials of wind energy extend beyond simple carbon displacement. Unlike solar panels, wind turbines occupy minimal ground space – typically less than half an acre including access roads – leaving surrounding land fully available for agriculture. This spatial efficiency proves particularly valuable in regions where arable land is scarce or expensive. Additionally, turbine foundations and access roads can improve farm infrastructure, facilitating easier movement of equipment and potentially increasing land values.

Recent research has challenged earlier concerns about wind turbines’ impact on wildlife, particularly birds and bats. While avian mortality does occur, studies indicate that properly sited turbines pose less risk than other anthropogenic factors such as domestic cats, building collisions, and vehicles. Modern turbines rotate more slowly than earlier models, making blades more visible to flying creatures. Furthermore, wildlife-friendly siting practices – avoiding migration corridors and breeding areas – can reduce ecological impacts to minimal levels. Some studies even suggest that the areas around turbine bases can serve as wildlife habitats, with vegetation and small structures providing shelter for various species.

The intermittent nature of wind energy presents both challenges and opportunities for agricultural operations. Wind speeds vary diurnally and seasonally, with many regions experiencing stronger winds at night when electricity demand traditionally drops. This temporal mismatch initially hindered wind energy adoption, but emerging storage technologies are transforming the landscape. Battery storage systems, though currently expensive, allow farms to store excess wind-generated electricity for use during peak demand periods when prices are highest. Some innovative farmers are using surplus wind power to produce hydrogen fuel through electrolysis, creating another marketable commodity.

Grid integration remains a significant technical challenge for widespread agricultural wind adoption. Rural electrical infrastructure was designed for unidirectional power flow – from centralized plants to distributed consumers. Modern distributed generation reverses this paradigm, with farms becoming electricity producers. Upgrading rural grids to handle bidirectional power flows requires substantial investment in smart grid technologies, including advanced metering, automated switching, and load balancing systems. Many countries have struggled to coordinate these upgrades, creating bottlenecks that prevent farmers from connecting wind turbines to the grid.

Policy frameworks significantly influence wind energy adoption rates in agricultural sectors. Feed-in tariffs – guaranteed above-market prices for renewable electricity – have proven highly effective in countries like Germany and Spain, where agricultural wind capacity expanded rapidly following policy implementation. Conversely, regions lacking clear regulatory frameworks often see minimal adoption despite favorable wind resources. Permitting processes vary dramatically between jurisdictions; some allow turbine installation with minimal paperwork, while others impose lengthy environmental reviews that delay projects for years.

Community acceptance represents another critical factor determining wind energy success. While many rural residents embrace turbines as economic development opportunities, others oppose them due to aesthetic concerns, noise, or property value impacts. Shadow flicker – the strobing effect created when turbine blades pass between the sun and nearby buildings – can be disruptive to neighbors. Successful projects typically involve extensive community consultation, fair benefit-sharing arrangements, and careful attention to siting decisions. Some developers offer local residents equity stakes in wind projects, aligning community interests with project success.

Looking forward, technological innovations promise to expand wind energy’s agricultural applications. Vertical-axis turbines, which rotate around a vertical pole rather than a horizontal axis, require less space and handle turbulent winds better than conventional designs. These characteristics make them suitable for farmyard installations where traditional turbines would be impractical. Additionally, offshore wind farms near coastal agricultural regions could provide clean electricity to support energy-intensive operations such as greenhouse heating, aquaculture, and food processing facilities, creating synergies between marine and terrestrial food production systems.

Questions 14-26

Questions 14-17: Yes/No/Not Given

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

14. Wind turbines require more land space than solar panels for equivalent energy production.
15. Early wind turbines were reliable and economically viable for most farmers.
16. Lease payments for wind turbines provide more stable income than crop sales.
17. All rural communities enthusiastically support wind turbine installation.

Questions 18-22: Matching Headings

Choose the correct heading (i-viii) for paragraphs B-F from the list below.

List of Headings:

• i. Financial models for agricultural wind energy
• ii. The history of wind power development
• iii. Wildlife concerns and modern research findings
• iv. Comparing wind and solar energy costs
• v. Environmental advantages of wind turbines
• vi. International wind energy statistics
• vii. Storage solutions for intermittent energy
• viii. Technical challenges in connecting farms to electrical grids

18. Paragraph B (starting with “The economics of farm-based…”)
19. Paragraph C (starting with “Lease arrangements…”)
20. Paragraph E (starting with “The environmental credentials…”)
21. Paragraph F (starting with “Recent research has challenged…”)
22. Paragraph H (starting with “Grid integration remains…”)

Questions 23-26: Summary Completion

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

Wind energy offers farmers opportunities to generate income while maintaining agricultural activities. A typical modern turbine can produce enough electricity for several hundred homes. Farmers can either lease their land to energy companies or purchase turbines and sell electricity through (23) __. The environmental benefits include minimal land use and improved (24) __. While concerns existed about impacts on birds and bats, research shows that (25) __ can minimize ecological damage. Future developments include (26) __ that work better in turbulent conditions and require less space.

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PASSAGE 3 – Biogas Systems and Circular Economy in Sustainable Agriculture

Độ khó: Hard (Band 7.0-9.0)

Thời gian đề xuất: 23-25 phút

The paradigmatic shift toward sustainable agriculture necessitates not merely the adoption of renewable energy sources, but the fundamental reconceptualization of farms as integrated bioeconomic systems where waste streams become valuable inputs and energy production intertwines with food cultivation. Among the various green energy technologies applicable to agricultural settings, anaerobic digestion systems for biogas production represent perhaps the most sophisticated manifestation of circular economy principles, transforming organic residues into both renewable energy and nutrient-rich fertilizers while simultaneously addressing critical environmental challenges associated with conventional waste management practices.

Anaerobic digestion constitutes a biological process wherein microorganisms decompose organic matter in oxygen-free conditions, producing biogas – primarily composed of methane (55-70%) and carbon dioxide (30-45%) – alongside a nutrient-dense residue called digestate. This process occurs naturally in environments such as swamps and animal digestive systems, but engineered anaerobic digesters optimize conditions to maximize gas production and processing speed. The versatility of feedstocks amenable to anaerobic digestion distinguishes biogas systems from other renewable technologies; manure, crop residues, food processing waste, and purpose-grown energy crops can all serve as inputs, providing farmers with flexibility to utilize whatever organic materials are most abundant on their operations.

The thermodynamic efficiency of biogas systems significantly exceeds that of alternative bioenergy pathways. When organic waste decomposes aerobically or in landfills, much of its energy content dissipates as heat while releasing greenhouse gases into the atmosphere. Anaerobic digestion captures this energy in chemical form, with each cubic meter of biogas containing approximately 6 kilowatt-hours of energy – equivalent to half a liter of diesel fuel. Combined heat and power (CHP) systems can convert biogas into both electricity and useful heat, achieving overall energy conversion efficiencies approaching 85-90%, substantially higher than the 35-45% typical of conventional power plants. This remarkable efficiency enables medium and large-scale livestock operations to achieve energy self-sufficiency while generating surplus electricity for grid sales or neighboring facilities.

The agronomic benefits of digestate underscore biogas systems’ alignment with regenerative agriculture principles. Unlike raw manure, which contains pathogens, weed seeds, and malodorous compounds, digestate undergoes pathogen reduction during the digestion process and emerges as a stabilized organic fertilizer with enhanced plant availability of nutrients. The carbon-to-nitrogen ratio in digestate typically ranges from 8:1 to 15:1, optimal for soil application, and the process converts organic nitrogen into ammonium nitrogen, which plants readily absorb. Research indicates that substituting synthetic fertilizers with digestate can reduce a farm’s carbon footprint by 30-40% while maintaining or improving crop yields, simultaneously addressing two critical sustainability challenges: fossil fuel dependency in fertilizer production and nutrient runoff pollution in waterways.

Economic assessments of agricultural biogas systems reveal considerable complexity, with profitability contingent upon numerous interrelated factors including feedstock availability, system scale, energy prices, and policy incentives. Capital costs for farm-scale digesters range from $400 to $5,000 per kilowatt of installed capacity, with larger systems benefiting from economies of scale. A 500-kilowatt biogas plant serving a 1,000-cow dairy operation might require an initial investment of $1.5-2 million, offset by annual revenues of $200,000-300,000 from electricity sales, tipping fees for processing off-farm organic wastes, and reduced fertilizer expenses. Payback periods typically span 7-12 years absent subsidies, though favorable policy frameworks can reduce this to 4-6 years, making projects financially attractive even for risk-averse agricultural enterprises.

The policy landscape surrounding agricultural biogas varies dramatically across jurisdictions, profoundly influencing adoption rates. Germany’s Renewable Energy Act, implemented in 2000 and subsequently revised, guaranteed premium prices for biogas-derived electricity and stimulated explosive growth; by 2020, approximately 9,500 biogas plants operated nationally, with agricultural facilities accounting for over 75% of installations. This contrasts sharply with the United States, where fragmented state-level policies and lower natural gas prices have constrained biogas development despite substantial technical potential. The European Union’s Renewable Energy Directive mandates that member states achieve specific renewable energy targets, with biogas recognized as particularly valuable due to its dispatchability – unlike intermittent solar and wind resources, biogas can generate electricity on demand, providing grid stability services worth premium prices in modern electricity markets.

Environmental externalities associated with biogas systems extend beyond direct greenhouse gas mitigation. Conventional manure management practices on livestock farms often involve storage in open lagoons where anaerobic conditions develop spontaneously, releasing significant quantities of methane – a greenhouse gas 28 times more potent than carbon dioxide over a 100-year timeframe – directly to the atmosphere. Capturing and combusting this methane through biogas systems eliminates these fugitive emissions while extracting energy value. Additionally, reducing reliance on synthetic nitrogen fertilizers manufactured via the Haber-Bosch process – which consumes 1-2% of global energy supply and generates corresponding carbon emissions – multiplies the climate change mitigation potential of biogas-digestate systems. Life cycle analyses consistently demonstrate that substituting conventional manure management and fossil-based fertilizers with integrated biogas systems can achieve greenhouse gas emission reductions of 50-80% per unit of agricultural output.

Technical challenges nonetheless constrain biogas adoption in certain agricultural contexts. Feedstock characteristics critically influence digestion efficiency and biogas quality; high lignocellulose content in straw and woody materials resists microbial breakdown, while excessive sulfur concentrations produce hydrogen sulfide, a corrosive compound requiring costly gas cleaning systems. Process stability demands careful monitoring and management, as the methanogenic microorganisms responsible for biogas production are sensitive to temperature fluctuations, pH changes, and inhibitory substances. Small-scale systems often struggle to maintain the technical expertise necessary for optimal operation, leading to suboptimal performance or system failures. Emerging digital agriculture technologies, including remote monitoring platforms and artificial intelligence-based process control, promise to address these challenges by enabling predictive maintenance and automated optimization, potentially making sophisticated biogas systems manageable even for smaller operations.

The integration of biogas systems with other renewable energy technologies creates opportunities for synergistic optimization. Hybrid systems combining anaerobic digestion with solar thermal collectors can maintain optimal digester temperatures year-round without fossil fuel inputs, improving both energy balance and economic returns. Power-to-gas technologies, though currently expensive, can utilize surplus electricity from solar and wind installations to produce renewable hydrogen via electrolysis, which can then be biologically converted into methane through methanation processes using carbon dioxide from biogas upgrading – effectively storing intermittent renewable energy in stable, energy-dense biogas form. Such sector coupling strategies represent frontier developments in integrated renewable energy systems, transforming farms from simple food producers into sophisticated energy hubs that enhance overall grid flexibility while advancing agricultural sustainability.

Future trajectories for agricultural biogas systems will likely emphasize distributed generation networks rather than isolated installations. Collaborative biogas plants serving multiple farms can achieve scale economies while distributing investment burdens and operational responsibilities across participants. In regions with high livestock density, centralized biogas facilities processing organic wastes from numerous sources – farms, food processors, municipal organic wastes – can attain impressive efficiencies and revenues while providing valuable waste management services. Such models require sophisticated governance structures and benefit-sharing mechanisms to ensure equitable outcomes, yet successful examples in Denmark, Austria, and Switzerland demonstrate their viability. As climate imperatives intensify and circular economy concepts gain policy traction, biogas systems integrating waste valorization, renewable energy production, and nutrient recycling appear positioned to become foundational elements of sustainable agricultural landscapes globally.

Questions 27-40

Questions 27-31: Multiple Choice

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

27. According to the passage, anaerobic digestion is best described as:

    • A) A chemical process that burns organic waste
    • B) A biological process where microorganisms decompose organic matter without oxygen
    • C) A mechanical system that compresses agricultural residues
    • D) A solar-powered waste treatment method

28. Each cubic meter of biogas contains energy equivalent to:

    • A) One liter of diesel fuel
    • B) Two liters of diesel fuel
    • C) Half a liter of diesel fuel
    • D) One-quarter liter of diesel fuel

29. The carbon-to-nitrogen ratio in digestate is optimal for soil application at:

    • A) 5:1 to 8:1
    • B) 8:1 to 15:1
    • C) 15:1 to 25:1
    • D) 25:1 to 30:1

30. By 2020, how many biogas plants were operating in Germany?

    • A) Approximately 5,000
    • B) About 7,500
    • C) Around 9,500
    • D) Over 12,000

31. Methane is how many times more potent as a greenhouse gas than carbon dioxide over a 100-year period?

    • A) 10 times
    • B) 18 times
    • C) 28 times
    • D) 38 times

Questions 32-36: Matching Features

Match the benefits (A-H) with the biogas system features (Questions 32-36).

Features:
32. Combined heat and power systems
33. Digestate application
34. Capturing methane from manure
35. Power-to-gas technologies
36. Collaborative biogas plants

Benefits:

• A) Reduces pathogen levels in fertilizer
• B) Achieves 85-90% energy conversion efficiency
• C) Eliminates fugitive emissions from livestock farms
• D) Stores intermittent renewable energy
• E) Distributes investment costs across multiple farms
• F) Increases crop resistance to pests
• G) Improves soil water retention capacity
• H) Reduces transportation costs for feed

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 microorganisms are responsible for producing biogas in anaerobic digesters?
38. What is the typical payback period for biogas systems when favorable policy frameworks are in place?
39. What percentage of global energy supply does the Haber-Bosch process consume?
40. What emerging technology can enable predictive maintenance and automated optimization of biogas systems?

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Answer Keys – Đáp Án

PASSAGE 1: Questions 1-13

1. B
2. C
3. C
4. B
5. C
6. FALSE
7. TRUE
8. FALSE
9. FALSE
10. photovoltaic (PV)
11. weather
12. 25%
13. thin-film

PASSAGE 2: Questions 14-26

14. NO
15. NO
16. YES
17. NO
18. i
19. i
20. v
21. iii
22. viii
23. power purchase agreements (hoặc PPAs)
24. farm infrastructure
25. wildlife-friendly siting practices (hoặc siting practices)
26. vertical-axis turbines

PASSAGE 3: Questions 27-40

27. B
28. C
29. B
30. C
31. C
32. B
33. A
34. C
35. D
36. E
37. methanogenic microorganisms
38. 4-6 years
39. 1-2%
40. artificial intelligence (hoặc AI)

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Giải Thích Đáp Án Chi Tiết

Passage 1 – Giải Thích

Câu 1: B

• Dạng câu hỏi: Multiple Choice
• Từ khóa: primary reason, farmers, adopting solar power
• Vị trí trong bài: Đoạn 1, dòng 2-4
• Giải thích: Bài đọc nêu rõ “many farmers worldwide are turning to green energy solutions to reduce costs and environmental impact”. Đây là lý do chính được nhắc đến đầu tiên trong passage, paraphrase trực tiếp từ câu hỏi. Các đáp án khác không được đề cập như là lý do chính.

Câu 2: C

• Dạng câu hỏi: Multiple Choice
• Từ khóa: solar panel prices, since 2010
• Vị trí trong bài: Đoạn 2, dòng 3-4
• Giải thích: Passage viết: “prices dropping by approximately 70% since 2010”. Đây là thông tin rõ ràng về sự giảm giá của tấm pin mặt trời.

Câu 6: FALSE

• Dạng câu hỏi: True/False/Not Given
• Từ khóa: solar water pumps, maintenance, diesel pumps
• Vị trí trong bài: Đoạn 3, dòng 5-6
• Giải thích: Bài viết: “Modern solar water pumps eliminate fuel costs entirely and require minimal maintenance” ngược lại với câu phát biểu rằng solar pumps cần nhiều bảo trì hơn diesel pumps.

Câu 7: TRUE

• Dạng câu hỏi: True/False/Not Given
• Từ khóa: Netherlands, leader, greenhouse agriculture, Europe
• Vị trí trong bài: Đoạn 4, dòng 4-5
• Giải thích: Passage nêu rõ: “In the Netherlands, which leads Europe in greenhouse agriculture”. Đây là paraphrase trực tiếp của câu phát biểu.

Câu 10: photovoltaic (PV)

• Dạng câu hỏi: Sentence Completion
• Từ khóa: Solar panels, referred to as
• Vị trí trong bài: Đoạn 2, dòng 1
• Giải thích: Câu đầu tiên của đoạn 2 viết: “Solar panels, also known as photovoltaic (PV) systems”. Đây là từ đồng nghĩa chính xác.

Hệ thống tưới tiêu nông nghiệp sử dụng năng lượng mặt trời tiết kiệm chi phí và thân thiện môi trường

Passage 2 – Giải Thích

Câu 14: NO

• Dạng câu hỏi: Yes/No/Not Given
• Từ khóa: Wind turbines, more land space, solar panels
• Vị trí trong bài: Đoạn E, dòng 1-3
• Giải thích: Passage viết: “Unlike solar panels, wind turbines occupy minimal ground space – typically less than half an acre including access roads”. Điều này mâu thuẫn trực tiếp với phát biểu rằng wind turbines cần nhiều đất hơn.

Câu 15: NO

• Dạng câu hỏi: Yes/No/Not Given
• Từ khóa: Early wind turbines, reliable, economically viable
• Vị trí trong bài: Đoạn B, dòng 1-3
• Giải thích: Bài viết: “Early wind turbines were inefficient and prone to mechanical failures, making them economically unviable for most agricultural applications”. Đây là phản bác trực tiếp phát biểu.

Câu 16: YES

• Dạng câu hỏi: Yes/No/Not Given
• Từ khóa: Lease payments, stable income, crop sales
• Vị trí trong bài: Đoạn C, dòng 3-5
• Giải thích: Passage nêu: “These payments provide stable, predictable income that isn’t subject to the volatility of commodity prices or weather-related crop failures”. Writer đồng ý rằng lease payments ổn định hơn.

Câu 18: i (Financial models for agricultural wind energy)

• Dạng câu hỏi: Matching Headings
• Vị trí: Paragraph B
• Giải thích: Đoạn B thảo luận về “economics of farm-based wind energy” và đề cập đến modern turbines, capacity, revenue opportunities – tất cả liên quan đến các mô hình tài chính.

Câu 21: iii (Wildlife concerns and modern research findings)

• Dạng câu hỏi: Matching Headings
• Vị trí: Paragraph F
• Giải thích: Đoạn F bắt đầu với “Recent research has challenged earlier concerns about wind turbines’ impact on wildlife, particularly birds and bats” và tiếp tục thảo luận về avian mortality và wildlife-friendly practices.

Câu 23: power purchase agreements (hoặc PPAs)

• Dạng câu hỏi: Summary Completion
• Từ khóa: purchase turbines, sell electricity
• Vị trí trong bài: Đoạn D, dòng 1-2
• Giải thích: Passage viết: “some farmers choose to purchase and operate turbines independently, selling electricity directly to the grid through power purchase agreements (PPAs)”.

Passage 3 – Giải Thích

Câu 27: B

• Dạng câu hỏi: Multiple Choice
• Từ khóa: anaerobic digestion, described as
• Vị trí trong bài: Đoạn B, dòng 1-2
• Giải thích: Định nghĩa chính xác: “Anaerobic digestion constitutes a biological process wherein microorganisms decompose organic matter in oxygen-free conditions”. Đây là mô tả khoa học chính xác của quá trình.

Câu 28: C

• Dạng câu hỏi: Multiple Choice
• Từ khóa: cubic meter, biogas, energy equivalent
• Vị trí trong bài: Đoạn C, dòng 3-4
• Giải thích: Passage nêu rõ: “each cubic meter of biogas containing approximately 6 kilowatt-hours of energy – equivalent to half a liter of diesel fuel”.

Câu 31: C

• Dạng câu hỏi: Multiple Choice
• Từ khóa: methane, potent, greenhouse gas, 100-year period
• Vị trí trong bài: Đoạn G, dòng 2-4
• Giải thích: Bài viết: “methane – a greenhouse gas 28 times more potent than carbon dioxide over a 100-year timeframe”. Đây là số liệu cụ thể và chính xác.

Câu 32: B

• Dạng câu hỏi: Matching Features
• Feature: Combined heat and power systems
• Vị trí trong bài: Đoạn C, dòng 5-7
• Giải thích: Passage viết: “Combined heat and power (CHP) systems can convert biogas into both electricity and useful heat, achieving overall energy conversion efficiencies approaching 85-90%”. Match với benefit B.

Câu 34: C

• Dạng câu hỏi: Matching Features
• Feature: Capturing methane from manure
• Vị trí trong bài: Đoạn G, dòng 3-5
• Giải thích: “Capturing and combusting this methane through biogas systems eliminates these fugitive emissions while extracting energy value”. Match với benefit C về eliminating fugitive emissions.

Câu 37: methanogenic microorganisms

• Dạng câu hỏi: Short-answer Questions
• Từ khóa: microorganisms, responsible, producing biogas
• Vị trí trong bài: Đoạn H, dòng 3-4
• Giải thích: Passage viết: “the methanogenic microorganisms responsible for biogas production”. Đây là thuật ngữ khoa học chính xác cho vi sinh vật sản xuất khí biogas.

Câu 38: 4-6 years

• Dạng câu hỏi: Short-answer Questions
• Từ khóa: payback period, favorable policy frameworks
• Vị trí trong bài: Đoạn E, dòng 5-7
• Giải thích: Bài viết: “Payback periods typically span 7-12 years absent subsidies, though favorable policy frameworks can reduce this to 4-6 years”.

Câu 40: artificial intelligence

• Dạng câu hỏi: Short-answer Questions
• Từ khóa: emerging technology, predictive maintenance, automated optimization
• Vị trí trong bài: Đoạn H, dòng 6-8
• Giải thích: Passage nêu: “Emerging digital agriculture technologies, including remote monitoring platforms and artificial intelligence-based process control, promise to address these challenges by enabling predictive maintenance and automated optimization”.

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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	Integration of renewable energy into farming practices	renewable energy sources, renewable energy systems
photovoltaic	adj	/ˌfəʊtəʊvɒlˈteɪɪk/	quang điện, pin mặt trời	Solar panels, also known as photovoltaic (PV) systems	photovoltaic cells, photovoltaic technology
economically viable	adj phrase	/ˌiːkəˈnɒmɪkli ˈvaɪəbl/	khả thi về mặt kinh tế	Made solar technology economically viable for small farms	economically viable option, economically viable solution
irrigation	n	/ˌɪrɪˈɡeɪʃn/	tưới tiêu	Solar-powered irrigation eliminates fuel costs	irrigation system, irrigation pump
greenhouse farming	n	/ˈɡriːnhaʊs ˈfɑːmɪŋ/	trồng trọt nhà kính	Greenhouse farming requires substantial energy	greenhouse agriculture, greenhouse production
net-zero energy	adj	/net ˈzɪərəʊ ˈenədʒi/	năng lượng bằng không (sản xuất bằng tiêu thụ)	Operate as net-zero energy buildings	net-zero emissions, net-zero carbon
agrivoltaics	n	/ˌæɡrɪvɒlˈteɪɪks/	hệ thống kết hợp nông nghiệp và điện mặt trời	This approach, called agrivoltaics	agrivoltaic systems, agrivoltaic technology
battery storage	n	/ˈbætəri ˈstɔːrɪdʒ/	lưu trữ pin	Necessitating battery storage systems	battery storage capacity, battery storage solutions
financial incentives	n	/faɪˈnænʃl ɪnˈsentɪvz/	ưu đãi tài chính	Government offers financial incentives	financial incentive programs, provide financial incentives
climate change mitigation	n phrase	/ˈklaɪmət tʃeɪndʒ ˌmɪtɪˈɡeɪʃn/	giảm thiểu biến đổi khí hậu	Contribute to climate change mitigation	climate mitigation strategies, climate mitigation efforts
sustainable food production	n phrase	/səˈsteɪnəbl fuːd prəˈdʌkʃn/	sản xuất lương thực bền vững	Essential for sustainable food production	sustainable production systems, sustainable production methods
carbon emissions	n	/ˈkɑːbən ɪˈmɪʃnz/	khí thải carbon	Reducing carbon emissions significantly	carbon emission reduction, carbon emission levels

Tua-bin điện gió trên cánh đồng nông nghiệp tạo năng lượng sạch không gây ảnh hưởng canh tác

Passage 2 – Essential Vocabulary

Từ vựng	Loại từ	Phiên âm	Nghĩa tiếng Việt	Ví dụ từ bài	Collocation
diversify income streams	v phrase	/daɪˈvɜːsɪfaɪ ˈɪnkʌm striːmz/	đa dạng hóa nguồn thu nhập	Farmers seeking to diversify income streams	diversify revenue, diversify sources
wind turbines	n	/wɪnd ˈtɜːbaɪnz/	tua-bin gió	Wind turbines can be erected on agricultural land	wind turbine installation, wind turbine capacity
dual-use approach	n phrase	/ˈdjuːəl juːs əˈprəʊtʃ/	cách tiếp cận sử dụng kép	This dual-use approach allows farmers to continue	dual-use system, dual-use strategy
lease arrangements	n	/liːs əˈreɪndʒmənts/	thỏa thuận cho thuê	Lease arrangements represent the most common model	lease agreement, lease terms
power purchase agreements	n	/ˈpaʊə ˈpɜːtʃəs əˈɡriːmənts/	hợp đồng mua bán điện	Selling electricity through power purchase agreements (PPAs)	PPA terms, PPA contracts
cooperatives	n	/kəʊˈɒpərətɪvz/	hợp tác xã	Farmers often form cooperatives to share costs	farmer cooperatives, agricultural cooperatives
arable land	n	/ˈærəbl lænd/	đất canh tác	Particularly valuable where arable land is scarce	arable farmland, arable acreage
avian mortality	n	/ˈeɪviən mɔːˈtæləti/	tỷ lệ chết của chim	Concerns about avian mortality from turbines	avian collision, avian fatalities
intermittent nature	n phrase	/ˌɪntəˈmɪtənt ˈneɪtʃə/	tính gián đoạn	The intermittent nature of wind energy	intermittent supply, intermittent generation
distributed generation	n	/dɪˈstrɪbjuːtɪd ˌdʒenəˈreɪʃn/	phát điện phân tán	Modern distributed generation reverses this paradigm	distributed energy, distributed power
feed-in tariffs	n	/fiːd ɪn ˈtærɪfs/	giá thu mua điện ưu đãi	Feed-in tariffs have proven highly effective	feed-in tariff scheme, feed-in tariff rates
shadow flicker	n	/ˈʃædəʊ ˈflɪkə/	hiện tượng nhấp nháy bóng	Shadow flicker created when turbine blades pass	shadow flicker effect, shadow flicker impact
vertical-axis turbines	n	/ˈvɜːtɪkl ˈæksɪs ˈtɜːbaɪnz/	tua-bin trục dọc	Vertical-axis turbines require less space	vertical-axis design, vertical-axis configuration
grid integration	n	/ɡrɪd ˌɪntɪˈɡreɪʃn/	tích hợp lưới điện	Grid integration remains a significant challenge	grid connection, grid infrastructure
smart grid technologies	n	/smɑːt ɡrɪd tekˈnɒlədʒiz/	công nghệ lưới điện thông minh	Investment in smart grid technologies	smart grid systems, smart grid solutions

Passage 3 – Essential Vocabulary

Từ vựng	Loại từ	Phiên âm	Nghĩa tiếng Việt	Ví dụ từ bài	Collocation
circular economy	n	/ˈsɜːkjələr ɪˈkɒnəmi/	kinh tế tuần hoàn	Integration of circular economy principles	circular economy model, circular economy approach
anaerobic digestion	n	/ˌænəˈrəʊbɪk daɪˈdʒestʃən/	tiêu hóa kỵ khí	Anaerobic digestion systems for biogas production	anaerobic digestion process, anaerobic digestion technology
biogas	n	/ˈbaɪəʊɡæs/	khí sinh học	Producing biogas primarily composed of methane	biogas production, biogas plant
digestate	n	/daɪˈdʒesteɪt/	chất thải sau tiêu hóa	Nutrient-dense residue called digestate	digestate application, digestate fertilizer
feedstocks	n	/ˈfiːdstɒks/	nguyên liệu đầu vào	Versatility of feedstocks amenable to digestion	feedstock materials, feedstock availability
thermodynamic efficiency	n	/ˌθɜːməʊdaɪˈnæmɪk ɪˈfɪʃnsi/	hiệu suất nhiệt động lực học	Thermodynamic efficiency significantly exceeds	energy efficiency, conversion efficiency
combined heat and power	n phrase	/kəmˈbaɪnd hiːt ənd ˈpaʊə/	hệ thống nhiệt điện kết hợp	Combined heat and power (CHP) systems	CHP units, CHP technology
regenerative agriculture	n	/rɪˈdʒenərətɪv ˈæɡrɪkʌltʃə/	nông nghiệp tái sinh	Alignment with regenerative agriculture principles	regenerative farming, regenerative practices
pathogen reduction	n	/ˈpæθədʒən rɪˈdʌkʃn/	giảm mầm bệnh	Digestate undergoes pathogen reduction	pathogen removal, pathogen elimination
carbon footprint	n	/ˈkɑːbən ˈfʊtprɪnt/	dấu chân carbon	Reduce a farm’s carbon footprint by 30-40%	carbon footprint reduction, carbon footprint assessment
economies of scale	n phrase	/ɪˈkɒnəmiz əv skeɪl/	lợi thế kinh tế theo quy mô	Larger systems benefiting from economies of scale	achieve economies of scale, economies of scale benefits
greenhouse gas mitigation	n phrase	/ˈɡriːnhaʊs ɡæs ˌmɪtɪˈɡeɪʃn/	giảm thiểu khí nhà kính	Direct greenhouse gas mitigation benefits	GHG mitigation, mitigation strategies
fugitive emissions	n	/ˈfjuːdʒɪtɪv ɪˈmɪʃnz/	khí thải thoát ra	Eliminates fugitive emissions from manure	fugitive methane, fugitive gas
methanogenic microorganisms	n	/ˌmeθənəʊˈdʒenɪk ˌmaɪkrəʊˈɔːɡənɪzəmz/	vi sinh vật sinh metan	Methanogenic microorganisms responsible for biogas	methanogenic bacteria, methanogenic activity
power-to-gas	n	/ˈpaʊə tə ɡæs/	công nghệ chuyển điện thành khí	Power-to-gas technologies utilizing surplus electricity	power-to-gas conversion, power-to-gas systems
sector coupling	n	/ˈsektə ˈkʌplɪŋ/	liên kết ngành	Sector coupling strategies transform farms	sector integration, cross-sector coupling
distributed generation	n	/dɪˈstrɪbjuːtɪd ˌdʒenəˈreɪʃn/	phát điện phân tán	Future trajectories emphasize distributed generation	distributed energy resources, distributed power systems
waste valorization	n	/weɪst ˌvælərɪˈzeɪʃn/	tăng giá trị chất thải	Biogas systems integrating waste valorization	waste valorization processes, valorization strategies

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Kết bài

Chủ đề “Green energy for sustainable farming” không chỉ phản ánh xu hướng toàn cầu về phát triển bền vững mà còn là một trong những nội dung quan trọng thường xuyên xuất hiện trong kỳ thi IELTS Reading. Qua bộ đề thi mẫu này, bạn đã được tiếp cận với đầy đủ ba mức độ khó từ Easy đến Hard, giúp xây dựng kỹ năng đọc hiểu toàn diện.

Passage 1 cung cấp kiến thức nền tảng về năng lượng mặt trời trong nông nghiệp với từ vựng cơ bản và cấu trúc câu dễ hiểu. Passage 2 nâng cao độ phức tạp qua việc phân tích năng lượng gió, yêu cầu kỹ năng paraphrase và suy luận tốt hơn. Passage 3 thử thách người học với nội dung học thuật sâu về hệ thống biogas, đòi hỏi khả năng phân tích và hiểu các thuật ngữ chuyên ngành.

Với 40 câu hỏi đa dạng bao gồm 7 dạng khác nhau (Multiple Choice, True/False/Not Given, Yes/No/Not Given, Matching Headings, Matching Features, Sentence Completion, và Short-answer Questions), bạn đã luyện tập toàn diện các kỹ năng cần thiết cho bài thi thật. Phần đáp án chi tiết kèm giải thích cụ thể vị trí trong bài và cách paraphrase sẽ giúp bạn tự đánh giá chính xác và học từ những sai lầm.

Hãy thường xuyên luyện tập với các đề thi mẫu như thế này, chú ý phân tích các từ vựng quan trọng và áp dụng các chiến lược làm bài đã học. Sự kiên trì và phương pháp đúng đắn sẽ giúp bạn tự tin đạt band điểm mong muốn trong kỳ thi IELTS Reading sắp tới!