Band 8.0 IELTS Writing Task 1 Model Answer

Overall Band Score: 8.0 · Cambridge IELTS 14 · 2026-08-04

IELTS Writing Task 1 question

The diagram below shows how electricity is generated in a hydroelectric power station.

Summarise the information by selecting and reporting the main features, and make comparisons where relevant.

Student answer (Band 8.0)

The diagram illustrates the process by which electricity is generated in a hydroelectric power station. Overall, the system operates in a continuous cycle, using the movement of water to produce electricity during the day and pumping the water back to the upper reservoir at night.

During the daytime, water stored in a high-level reservoir is released through an intake, causing it to flow down a large pipe towards the power station. As the water passes through the turbines, they rotate and drive a generator, which converts the mechanical energy into electricity. The electricity is then transmitted via power lines to the national grid for distribution. After passing through the turbines, the water is discharged into a low-level reservoir.

At night, when electricity demand is lower, the process is reversed. Water from the lower reservoir is pumped back to the upper reservoir through the same pipe with the help of reversible turbines. This allows the upper reservoir to be replenished, ensuring that sufficient water is available to generate electricity again the following day. As a result, the hydroelectric power station can repeatedly produce electricity by recycling the same water.

AI examiner evaluation

Task Achievement / Task Response — Band 8.0

The response is excellent. You have clearly identified the main features of the hydroelectric power station, including the two distinct phases of the cycle (daytime generation and nighttime replenishment). The overview is concise and effectively summarizes the process. You have successfully integrated the information from the diagram into a logical narrative, highlighting the key components like the reservoirs, intake, turbines, and generator. The comparison between the daytime and nighttime operations is well-handled, demonstrating a clear understanding of the cyclical nature of the system. All parts of the task are addressed thoroughly.

Coherence and Cohesion — Band 8.0

The response is logically organized with a clear progression of ideas. You have used paragraphing effectively to separate the two main stages of the process, which helps the reader follow the sequence of events. Cohesive devices such as 'During the daytime', 'After passing through', 'At night', and 'As a result' are used naturally and accurately to link sentences and paragraphs. The flow of information is smooth, and the referencing is precise, ensuring that the relationship between the different parts of the power station is always clear.

Lexical Resource — Band 7.5

You have used a wide range of vocabulary appropriate for a technical description. Terms such as 'continuous cycle', 'mechanical energy', 'transmitted', 'distribution', and 'replenished' are used accurately and in the correct context. The language is precise and sophisticated, demonstrating a high level of control. There are no noticeable errors in word choice or collocation, and the vocabulary effectively conveys the technical nature of the process without being overly repetitive or simplistic.

Grammatical Range and Accuracy — Band 8.0

The response demonstrates a high level of grammatical accuracy and a good variety of complex structures. You have used passive voice appropriately for a process description (e.g., 'water is released', 'is transmitted', 'is pumped'), which is essential for this type of task. Sentence structures are varied, combining simple and complex sentences effectively. Punctuation is used correctly throughout, and there are no grammatical errors that impede communication. The control over tense and aspect is consistent and accurate.

See this exact question answered at other band scores — the same prompt compared across bands.

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