Band 6.5 IELTS Writing Task 1 Model Answer

Overall Band Score: 6.5 · Cambridge IELTS 12 · 2026-10-02

IELTS Writing Task 1 question

The diagram below shows how geothermal energy is used to produce electricity.

Summarise the information by selecting and reporting the main features, and make comparisons where relevant.

Student answer (Band 6.5)

The process diagram illustrates the steps involved in the production of electricity by a Geothermal power plant.

Overall, the power plant operates in five phases, starting from the pumping the cold water inside the earth strata and pumping up the hot water in the form of steam to operate the turbines for the generation of electricity.

The cold water is pumped down into the injection well which is about 4.5 km depth, until it reach at the geothermal zone of the earth, where cold water is converted into hot water due to the high temperature of hot rock. Then this hot water is extracted out to the condenser by means of the production well.

Steam is developed in the condenser chamber that is used to run the turbine, which is responsible for producing electricity by powering the generator. In the last step, the electricity is supplied to the nearest grid station.

AI examiner evaluation

Task Achievement / Task Response: Band 6.5

The response successfully addresses all parts of the task by providing an overview and outlining the main features of the geothermal energy production process, including key details like the 4.5 km depth and the stages from cold water injection to electricity generation. The overview clearly highlights that the plant operates in five phases and captures the core transformation sequence. However, some aspects are slightly under-developed or contain minor inaccuracies; for instance, the text mentions that 'Steam is developed in the condenser chamber', whereas the diagram indicates that water is pumped up to a condenser which then releases steam towards the turbine. To reach a higher band, the description of the mechanical and thermal stages should be presented with complete technical precision and slightly more extended elaboration on the intermediate phase transitions.

Coherence and Cohesion: Band 6.5

The response demonstrates a coherent overall arrangement with a clear logical progression from the initial injection of cold water underground to the final electricity supply at the grid station. Paragraphing is used appropriately to separate the introduction, overall summary, subsurface processes, and surface generation stages. Cohesive devices are employed to guide the reader through the process, such as 'Overall,' 'Then,' and 'In the last step.' However, cohesion occasionally feels somewhat mechanical or formulaic, and referencing could be smoother, as seen in transitions like 'until it reach at the geothermal zone'. To achieve a higher band, the student should employ a more sophisticated and flexible variety of cohesive ties, ensuring that relationships between sentences and clauses flow seamlessly without relying on repetitive connective patterns.

Lexical Resource: Band 6.5

The response exhibits an adequate range of vocabulary for the task, successfully attempting less common and subject-specific terms such as 'geothermal zone', 'injection well', 'production well', and 'condenser chamber'. Meaning is generally clear despite some lexical and collocational inaccuracies. For example, phrases like 'from the pumping the cold water' contain awkward verb forms, and 'until it reach at' conflates different prepositional structures. Spelling and word choice errors are present but do not impede overall communication. To move to a higher band, the writer needs to demonstrate greater precision in word selection, better control of collocations related to scientific processes, and fewer minor errors in lexical forms.

Grammatical Range and Accuracy: Band 6.0

The response employs a mix of simple and complex sentence forms, demonstrating an ability to construct multi-clause sentences such as 'where cold water is converted into hot water due to the high temperature of hot rock.' There is satisfactory control over basic punctuation and sentence boundaries. Nevertheless, there are noticeable grammatical errors throughout the text, including article omissions and tense/agreement slips, such as 'until it reach at' and 'pumping the cold water'. These errors persist but rarely impede communication, placing the grammar firmly in the mid-range band. To attain a higher band, the writer must produce a greater proportion of error-free complex sentences and exercise tighter control over prepositions, verb tenses, and article usage.

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

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