Band 6.0 IELTS Writing Task 1 Model Answer

Overall Band Score: 6.0 · Cambridge IELTS 14 · 2026-09-18

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 6.0)

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

Overall, the process consists of several stages, beginning with water being stored in a reservoir and ending with electricity being distributed to homes and businesses. During the process, water passes through a turbine, which powers a generator to produce electricity.

First, water is collected in a large reservoir behind a dam. When electricity is required, the intake gate is opened and water flows down through a large pipe called a penstock. The force of the moving water turns a turbine located at the bottom of the dam. The turbine is connected to a generator, which converts the mechanical energy into electrical energy.

Next, the electricity produced by the generator is sent to a transformer. The transformer increases the voltage so that electricity can be transmitted efficiently over long distances through power lines. Finally, the electricity is supplied to different areas for domestic and industrial use.

Meanwhile, after passing through the turbine, the water flows into the river downstream. Thus, the water can continue its natural cycle and potentially be used again in the hydroelectric power generation process.

AI examiner evaluation

Task Achievement / Task Response — Band 5.0

The student provides a clear overview of the hydroelectric power station process and outlines the main stages of electricity generation. However, the student misses a critical feature of the diagram: the cyclical nature of the system, specifically the night-time pumping mechanism where water is returned from the low-level reservoir to the high-level reservoir using reversible turbines. Instead, the student incorrectly describes the water flowing into a river downstream at the end. Because this omits a major part of the provided visual data and introduces inaccurate information not present in the prompt, Task Achievement cannot exceed Band 5.5.

Coherence and Cohesion — Band 6.0

The response is organized logically into clear paragraphs, moving from an introduction to the main generation steps, followed by transmission and an incorrect conclusion. Cohesive devices such as 'First', 'Next', and 'Finally' are used appropriately to guide the reader through the sequence. Paragraphing is handled well, with distinct breaks for each part of the description. However, the logical progression breaks down slightly in the final paragraphs due to the misinterpretation of the diagram's night cycle as a simple river runoff. Cohesion within paragraphs is generally smooth, earning a solid Band 6.5.

Lexical Resource — Band 5.5

The student demonstrates an adequate range of vocabulary suitable for describing a technical process, incorporating terms like 'reservoir', 'dam', 'intake gate', 'penstock', 'turbine', 'generator', 'transformer', and 'voltage'. There are some successful attempts at less common phrasing such as 'converts the mechanical energy into electrical energy'. Word choice is generally appropriate, though there are minor inaccuracies in interpreting the diagram's terminology. Spelling is accurate throughout the text, and communication is never impeded by lexical limitations.

Grammatical Range and Accuracy — Band 6.5

The student employs a good mix of simple and complex sentence structures, such as 'When electricity is required, the intake gate is opened and water flows down through a large pipe called a penstock.' Subordinate clauses and participial phrases ('water being stored', 'passing through the turbine') are used effectively. Grammatical accuracy is quite high; the majority of sentences are error-free, and control over tense (primarily simple present for processes) and punctuation is strong. Minor awkwardness does not impede understanding, reflecting a solid Band 7.0 performance for grammar.

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

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