Band 6.5 IELTS Writing Task 1 Model Answer

Overall Band Score: 6.5 · Cambridge IELTS 14 · 2026-09-21

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 given diagram illustrates the procees by which electricity is generated in a hydroelectric power station.

Overall, the station operates in sequence involving water storage in the upper reservoir, water flow through turbines for power generation, and the transfer of water to the lower reservoir. At instances, water is pumped back to the upper reservoir for the conservation of the given cycle.

To begin with, water is originally collected from a river and stored in a high-level reservoir behind a dam. During times of requirement, usually daytime, gates of intake are opened, allowing water to flow down through tubes into the power station. This flowing water turns the turbines, which power generators to create electricity. This generated electricity is then transmitted via power lines to the national grid for further use. After passing through given turbines, water is allowed to flow out and deposit into a low-level reservoir.

When electricity demand is low, usually at night, the process may be reversed. Water present in the low level reservoir is pumped back to the high-level reservoir using excess electricity, ready to released again if required.

AI examiner evaluation

Task Achievement / Task Response — Band 6.5

The student successfully addresses all parts of the task by providing a clear overview of the hydroelectric power station and detailing the cyclical process of electricity generation during the day and water pumping at night. The main features, such as the high-level and low-level reservoirs, the dam, intake valves, turbines, generators, and the national grid, are all accurately reported and logically connected. The overview effectively captures the dual daytime and nighttime operation modes without getting bogged down in minor details. The response satisfies the requirements of a Band 7.0 for Task Achievement by presenting a well-developed, accurate summary of the visual data.

Coherence and Cohesion — Band 6.5

The response is well-organized with clear logical progression throughout. It opens with an introductory sentence and an overarching summary paragraph, followed by two body paragraphs detailing the daytime and nighttime stages respectively. Cohesive devices are used effectively to guide the reader through the sequence of events, using transitional phrases like 'To begin with', 'During times of requirement', and 'When electricity demand is low'. Paragraphing is logical and contributes to the overall clarity of the essay. Referencing is generally clear, though occasional transitional links could be smoother. This performance corresponds to a Band 7.0 for Coherence and Cohesion.

Lexical Resource — Band 6.0

The student demonstrates an adequate to good range of vocabulary suited to a process diagram. Terms such as 'hydroelectric power station', 'reservoir', 'reversible turbines', 'generator', and 'national grid' are used accurately. However, there are a few minor lexical slips and awkward phrasing, notably the spelling error 'procees' in the first sentence and the phrase 'At instances' instead of 'At times' or 'On occasion'. Less common lexical items are attempted with some success, placing this response firmly in the Band 6.5 range, which we can round to 6.5 or 7.0 depending on control; here, the vocabulary is sufficient for precision, earning a solid Band 6.5.

Grammatical Range and Accuracy — Band 6.5

The student exhibits a good mix of simple and complex sentence structures, incorporating participial phrases and relative clauses (e.g., 'water originally collected from a river and stored...', 'allowing water to flow down...'). There are frequent error-free sentences, and grammar and punctuation are generally well controlled. A few minor grammatical inaccuracies exist, such as omitting articles in certain places ('low level reservoir', 'ready to released') and the spelling slip in the introduction. Nonetheless, these errors do not impede communication, and the structural variety supports a Band 7.0 descriptor.

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

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