Band 7.5 IELTS Writing Task 1 Model Answer

Overall Band Score: 7.5 · Cambridge IELTS 14 · 2026-08-26

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 7.5)

The illustration reveals the cyclical generation process of electricity in a hydroelectric power station.

At a glance, it is clear that the process consists of several distinct stages which operate differently depending on the time of day. During the daytime, the system utilizes a downward flow of water to produce electricity, whereas at night, the system reverses its operation to pump water back to the starting position.

Looking at the process diagram in detail, during the daytime, the intake is opened, which allows water to flow downward from the high-level reservoir. Next, this high-speed water flow reaches the reversible turbines that power the generator, ultimately producing electricity that is transmitted to the national grid. The used water is then collected and stored in the low-level reservoir.

At night, the intake is closed, and the reversible turbines are rotated in the opposite direction to act as pumps. Consequently, the water from the low-level reservoir is pumped in the reverse direction, returning to the high-level reservoir to complete the cycle and prepare for the next day.

AI examiner evaluation

Task Achievement / Task Response — Band 7.5

The response effectively covers all key stages of the hydroelectric power generation process. You have successfully identified the main features, such as the distinction between daytime and nighttime operations, and the role of the reversible turbines. The overview is clear and provides a good summary of the cyclical nature of the process. The information is well-selected, and the comparison between the two modes of operation is accurate and easy to follow. You have fully addressed the requirements of the task.

Coherence and Cohesion — Band 7.5

The response is logically organized, with a clear introduction, a body paragraph for each phase of the process, and a logical progression of ideas. Cohesive devices such as 'At a glance', 'Next', 'Consequently', and 'in the reverse direction' are used effectively to guide the reader through the sequence. Paragraphing is used appropriately to separate the daytime and nighttime operations, which enhances the clarity of the report. The flow of information is smooth and coherent throughout.

Lexical Resource — Band 7.5

You have used a range of vocabulary appropriate for a technical description, such as 'cyclical generation process', 'reversible turbines', 'national grid', and 'high-level reservoir'. The word choice is precise and contributes to a professional tone. There are no significant errors in collocation or spelling, and the vocabulary is used with a good degree of flexibility to describe the mechanical functions of the power station.

Grammatical Range and Accuracy — Band 7.5

The writing demonstrates a high level of grammatical accuracy. You have successfully employed a variety of complex sentence structures, such as the use of subordinate clauses ('whereas at night, the system reverses its operation...') and passive voice constructions ('electricity that is transmitted to the national grid'). Punctuation is used correctly to manage sentence flow. The majority of your sentences are error-free, and the control over tense and subject-verb agreement is consistent throughout the text.

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