Band 6.5 IELTS Writing Task 1 Model Answer

Overall Band Score: 6.5 · Cambridge IELTS 14 · 2026-10-01

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 6.5)

The diagram illustrates the process of generating electricity in a hydroelectric power station. Overall, the hydroelectric power generation is a continuous to and fro process of moving water from the river to the low-level reservoir to the high-level reservoir during day and night respectively.

Water flowing from the river is stored in the high-level reservoir with the help of dam. The water intake opens during the day allowing the water to flow from the reservoir through the turbines of the generator which convert the kinetic energy of the flowing water into electricity. The electricity generated is then stored inside the generator and transmitted through the power lines into the national grid.

The flowing water is kept inside the low-level reservoir which during the night is pumped back into the high-level reservoir. Flow of water is opposite at night as opposed to during the day. The water travels back through the same pipe and this continuous daily cycle keeps on generating hydroelectricity.

AI examiner evaluation

Task Achievement / Task Response: Band 6.0

The response addresses all parts of the task by providing an overview and describing the main stages of the hydroelectric power station process. The overview is reasonably clear, noting the continuous to-and-fro cycle between the high and low-level reservoirs during day and night. However, some aspects of the process are slightly under-developed or imprecise. For instance, stating that 'electricity generated is then stored inside the generator' is factually inaccurate according to the diagram, which shows electricity being transmitted directly through power lines to the national grid. Furthermore, the description of how water flows during the night misses some mechanical details such as the role of reversible turbines acting as pumps. To reach a higher band, the response should ensure complete accuracy in reporting visual data and extend the description of the nighttime cycle without technical inaccuracies.

Coherence and Cohesion: Band 6.5

The response exhibits a coherent overall arrangement with a clear logical progression from the initial river storage through daytime generation to nighttime pumping. Paragraphing is utilised appropriately to separate the introduction, the daytime process, and the nighttime cycle. Cohesive devices such as 'Overall', 'The water intake', and 'during the night' help guide the reader through the stages. However, some referencing is slightly faulty or mechanical, such as 'The flowing water is kept inside the low-level reservoir which during the night is pumped back', which creates slight clunkiness. To achieve a higher band, the transitions between sentences could be smoothed further, and referencing devices could be managed with greater flexibility to ensure seamless progression.

Lexical Resource: Band 6.5

The student uses an adequate range of vocabulary for the task, attempting less common items related to the diagram such as 'hydroelectric power generation', 'kinetic energy', and 'reversible turbines'. Word choices are generally appropriate and communication is not impeded by lexical errors. However, there are some minor inaccuracies in collocation and word choice, such as 'continuous to and fro process' instead of a cyclical process, and the misuse of 'stored inside the generator'. Spelling is accurate throughout. To move towards a higher band, the vocabulary could incorporate more precise scientific or process-oriented phrasing, and less common lexical items should be used with greater flexibility and stylistic awareness.

Grammatical Range and Accuracy: Band 6.5

The response demonstrates a mix of simple and complex sentence forms, incorporating relative clauses such as 'which convert the kinetic energy of the flowing water into electricity'. There is good control over basic structures, and punctuation is generally sound. However, some grammatical errors and awkward phrasing persist, such as missing articles ('with the help of dam' instead of 'with the help of a dam') and minor prepositional lapses ('flow of water is opposite at night'). These errors are typical of the band and rarely impede communication. To reach a higher band, the writer needs to produce a greater frequency of error-free complex sentences and refine article usage and prepositions within technical contexts.

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

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