Band 7.5 IELTS Writing Task 1 Model Answer

Overall Band Score: 7.5 · Cambridge IELTS 14 · 2026-08-20

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 diagram shows how a hydroelectric power station functions, demonstrating the process of electricity generation during the day and the method used to pump water back into the system at night.

Overall, the operation is a continuous cycle. Water flows from an elevated reservoir to produce electricity during daylight hours, while energy is used at night to pump the water back to the higher reservoir for future use. This method ensures a steady supply of electricity and helps conserve water for ongoing energy generation.

Throughout the day, water from the high-level reservoir, which is supplied by a river, flows through an open intake and drives turbines that can operate in reverse, which are connected to a generator. These turbines convert the kinetic energy of the water into electrical energy, which is then transmitted to the national grid. After the water passes through the turbines, it is collected in a lower reservoir.

At night, the intake is closed, and the station switches to pumping mode. In this phase, the turbines reverse their direction and use electricity from the grid to pump the water back from the low-level reservoir to the high-level reservoir, setting up the system for the next day's electricity generation cycle

AI examiner evaluation

Task Achievement / Task Response — Band 7.5

The response effectively addresses all parts of the task. You have clearly identified the main features of the hydroelectric power station, including the distinction between the daytime generation phase and the nighttime pumping phase. The overview is concise and provides a good summary of the process. You have successfully highlighted the cyclical nature of the system, which is a key feature of the diagram. The information is well-selected and logically grouped, ensuring that the reader can easily follow the sequence of events. No significant information is omitted, and the comparison between the two operational modes is clear and accurate.

Coherence and Cohesion — Band 7.5

The response is logically organized with a clear progression of ideas. You have used paragraphing effectively to separate the introduction, the general overview, and the two distinct phases of the process. Cohesive devices such as 'Throughout the day', 'After the water passes', and 'In this phase' are used appropriately to guide the reader through the stages of the cycle. The flow of information is smooth, and the relationship between the high-level reservoir, the turbines, and the low-level reservoir is clearly established. The use of referencing is precise, making the text easy to follow.

Lexical Resource — Band 7.0

You have demonstrated a good range of vocabulary appropriate for a technical description. Terms such as 'kinetic energy', 'national grid', 'elevated reservoir', and 'operational cycle' are used accurately and in the correct context. The vocabulary is sufficiently varied to describe the process without unnecessary repetition. While the language is clear and functional, incorporating a few more sophisticated collocations or precise technical verbs could elevate the response further. Overall, the lexical control is strong, and there are no errors that impede communication or cause confusion.

Grammatical Range and Accuracy — Band 7.5

The response displays a high level of grammatical accuracy. You have used a variety of complex sentence structures, such as relative clauses ('which is supplied by a river') and participial phrases ('setting up the system for the next day's electricity generation cycle'), with confidence. Punctuation is used correctly to manage sentence length and clarity. The majority of your sentences are error-free, and the control over verb tenses is consistent throughout the description. There are no noticeable grammatical slips, and the writing is fluent and professional.

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