🔁 1. Ôn tập – 10 phút
🔁 Ôn thẻ từ vựng đến hạn
🧠 Nhớ lại buổi trước (không xem tài liệu)
- Cụm danh từ: “Solar power has grown rapidly.” → ?
- “intermittent” nghĩa là gì?
- Multiple choice: 3 loại lựa chọn sai là gì?
Trả lời to hoặc viết ra giấy, rồi mới mở lại buổi trước để kiểm tra.
📖 2. Đầu vào – 20 phút
Solar power on the water
(Bài đọc tự viết; hồ chứa, kỹ sư và số liệu là giả định.)
A As countries try to expand renewable energy, one obstacle keeps appearing: space. Large solar farms are land-intensive, and in densely populated regions, suitable land is often already used for farming, housing or forests. Engineers have therefore begun to look in an unexpected direction – at the surface of lakes and reservoirs.
B Floating solar farms consist of panels mounted on platforms that rest on the water. The platforms are held in place by anchors and cables connected to the bottom or the banks of the reservoir. Electricity is carried to the shore through underwater cables and then fed into the grid.
C Supporters point to several advantages. The most obvious is that no farmland needs to be sacrificed. In addition, water tends to keep the panels cooler than they would be on land, and solar panels generally work more efficiently at lower temperatures. The panels also shade the water, which may reduce evaporation – a potentially valuable benefit for reservoirs that supply drinking water in hot, dry seasons.
D At the fictional Lam Son reservoir, engineer Thu Tran has overseen a pilot project covering a small fraction of the water’s surface. According to her team, the panels have produced slightly more electricity per panel than an identical system on nearby land, which she attributes mainly to the cooling effect. She stresses, however, that the pilot has run for only two years, and that results may differ in other climates.
E Floating systems also bring new challenges. Installing anchors in deep or uneven reservoirs can be costly, and equipment must be designed to withstand strong winds, waves and, in some places, floods. Maintenance is more complicated too: technicians need boats to reach the panels, and moisture can damage electrical parts over time.
F Ecologists raise a further question. By blocking sunlight, large floating farms could change the temperature and oxygen levels of the water below, with uncertain effects on fish and plants. Some scientists suggest that reduced light might limit the growth of algae, which could be beneficial in reservoirs where algae are a problem. Others warn that covering too much of the surface might harm the wider ecosystem. Most agree that more long-term research is needed before very large projects are approved.
G For now, floating solar is likely to remain one part of a broader strategy rather than a complete solution. Tran believes its greatest potential lies in reservoirs that already have electricity infrastructure nearby, such as those used for hydropower, where existing grid connections could be shared.
Câu 1–6: Complete the sentences. NO MORE THAN TWO WORDS from the passage.
- 1. Solar farms on land need a lot of space, which is why they are described as .
- 2. The floating platforms are kept in position by .
- 3. Electricity reaches the shore through .
- 4. Shading by the panels may lead to less from the reservoir.
- 5. Technicians must use to carry out maintenance.
- 6. Over time, can damage electrical components.
✅ Câu 7–10: chọn A, B, C hoặc D
7. According to paragraph C, why do panels on water work more efficiently?
8. What does Thu Tran say about the results of the pilot project?
9. What do ecologists agree on?
10. Where does Tran think floating solar has the most potential?
🧩 3. Ngôn ngữ trọng tâm – 10 phút: từ thận trọng trong văn bản khoa học
| Từ | Ý nghĩa với người đọc |
|---|---|
| tends to, generally | thường đúng, nhưng có ngoại lệ |
| may, might, could | có khả năng – chưa chắc |
| potentially valuable | có thể có giá trị |
| uncertain effects | ảnh hưởng chưa rõ |
| she attributes it mainly to… | đây là giải thích của cô ấy |
| more research is needed | chưa có kết luận chắc |
👉 Câu hỏi T/F/NG hoặc MC dùng từ chắc chắn (always, prove, certainly) khi bài chỉ nói may → thường sai.
✍️ 4. Thực hành – 25 phút
- Với câu 8 và 9: giải thích vì sao từng lựa chọn sai là đúng một nửa / không có / quá mạnh (10 phút).
- Gạch mọi từ thận trọng trong đoạn C, D, F (5 phút).
- Nói 1–2 phút: Việt Nam có nên phát triển điện mặt trời nổi không? Lợi ích và rủi ro? (10 phút).
💼 Dùng ngay – đọc hóa đơn tiền điện (thêm 5–10 phút)
(Hóa đơn và đơn giá giả định – không phải biểu giá thật.)
| Item | Details | Amount (VND) |
|---|---|---|
| Consumption | 320 kWh (meter: 15,420 → 15,740) | |
| Tier 1 (0–100 kWh) | 100 × 1,800 | 180,000 |
| Tier 2 (101–200 kWh) | 100 × 2,100 | 210,000 |
| Tier 3 (201+ kWh) | 120 × 2,600 | 312,000 |
| VAT 8% | 56,160 | |
| Total | 758,160 |
✅ Hiểu hóa đơn
How was the consumption of 320 kWh calculated?
Why is the price per kWh not the same for all 320 kWh?
If you reduced consumption by 120 kWh, which tier would you avoid completely?
📚 Từ vựng của buổi
- reservoir – hồ chứa
The reservoir supplies drinking water.
- evaporation – sự bốc hơi
Shade reduces evaporation.
- efficiency – hiệu suất
Panels work with higher efficiency when cool.
- anchor – neo; mỏ neo
The platforms are anchored to the bottom.
- ecosystem – hệ sinh thái
The project may affect the ecosystem.
- algae – tảo
Algae can be a problem in warm water.
- land-intensive – tốn nhiều đất
Solar farms are land-intensive.
- maintenance – bảo trì
Maintenance requires boats.
- tariff – biểu giá
Electricity tariffs rise in tiers.
- consumption – mức tiêu thụ
Our consumption was 320 kWh.
✅ 5. Tự kiểm tra – 10 phút
✅ Tự kiểm tra
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