Band 6.5 IELTS Writing Task 1 Model Answer

Overall Band Score: 6.5 · Cambridge IELTS 14 · 2026-09-22

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 provided graph illustrates the generation of electricity in a hydroelectric power station.

Overall, the different steps are divided in two main phases: during the day and at night. In day-time, the process starts at the high-level reservoir and ends in the low-level one, whereas at night is the complete opposite.

Firstly, in daylight, the water of the river passes through the high-level reservoir and it is cointained in a dam. Next, water falls down through a tube to generate electricity, thanks to the intake which is only opened in day time. Following this, water arrives at the power station, where the reversible turbines operate the generator. The generator sends water into two different tubes, one that goes directly into the low level-reservoir or up to the power lines, before going to the national grid.

At night, the process is opposite. The power station pumps water from the low-level reservoir to the high-level one, following similar steps. After the power station pumps the flow of water into the tube it finally arrives in the high-level reservoir, where the intake is closed.

AI examiner evaluation

Task Achievement / Task Response — Band 6.5

The student successfully identifies the main features of the hydroelectric power station diagram, correctly contrasting the day and night cycles as requested. The overview effectively captures the two-phase nature of the process. However, there are some minor inaccuracies in reporting specific mechanical steps: for instance, the generator does not send water into tubes, but rather sends electricity via power lines to the national grid. Despite these minor misreadings of the diagram's arrows and labels, all parts of the task are addressed with a clear overarching structure, earning a solid Band 6.5 score.

Coherence and Cohesion — Band 7.0

The response demonstrates a coherent overall arrangement with clear paragraphing that separates the introduction, the day cycle, and the night cycle. Cohesive devices such as 'Overall', 'Firstly', 'Next', 'Following this', and 'At night' are used to guide the reader through the stages of the process. While some of the transitions and referencing are occasionally mechanical or slightly imprecise—such as 'whereas at night is the complete opposite'—the logical progression remains clear throughout the text, fully supporting a Band 7.0 score.

Lexical Resource — Band 6.0

The student uses an adequate range of vocabulary suitable for describing a process, including terms like 'generation', 'reservoir', 'turbines', 'generator', and 'intake'. There are some successful attempts at less common vocabulary ('cointained', 'daylight'). However, minor spelling errors ('cointained') and occasional awkward phrasing or word choice—such as stating that the generator 'sends water into two different tubes'—prevent a higher score. The vocabulary is sufficient for the task and does not impede communication, comfortably fitting Band 6.0 descriptors.

Grammatical Range and Accuracy — Band 6.0

The response incorporates a mix of simple and complex sentence forms, utilizing relative clauses and time-dependent subordinate clauses effectively (e.g., 'where the reversible turbines operate the generator', 'which is only opened in day time'). There are some grammatical errors, such as missing prepositions or article inconsistencies ('in day-time', 'at night is the complete opposite'), but these errors rarely impede communication and the majority of sentences are constructed without severe faults. This performance aligns well with the Band 6.0 criteria.

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

Browse more IELTS Writing model answers or get your own writing scored by the same AI examiner.