Academic Writing Task 1 · process diagram

A diagram illustrating the process of generating electricity from a dam: IELTS Writing Task 1 sample answer

An IELTS Writing Task 1 process diagram question with a Band 8 sample answer, the chart redrawn with its data, the vocabulary that lifts the report and how to write about process diagrams.
  • 182 words
  • Process diagrams
  • Academic
  • 20 minutes

The question

The diagram shows the production of hydroelectricity.

Summarise the information by selecting and reporting the main features, and make comparisons where relevant. Write at least 150 words.

The production of hydroelectricity
  1. 1.Water is stored in a reservoir behind a dam
  2. 2.Water flows through an intake into a penstock
  3. 3.The flowing water spins a turbine
  4. 4.The turbine powers a generator in the powerhouse
  5. 5.Electricity is transmitted via long distance power lines
  6. 6.Water exits into the river

Chart redrawn by BandLadder from the data in the original IELTS practice task. Many IELTS practice tasks come from the Cambridge IELTS series (Cambridge University Press & Assessment); all rights in the original tasks remain with their owners.

Model answer

Band 8 sample answer

Band 8182 words. Every figure in the answer comes from the chart above.

The provided diagram illustrates the mechanism by which a hydroelectric dam generates electricity. Overall, the process is a continuous cycle that relies on the gravitational flow of water from a reservoir to drive mechanical components, ultimately producing power for long-distance distribution.

In the initial stage, water is held in a large reservoir behind the dam structure. When electricity production is required, the water passes through an intake and travels down a large pipe known as a penstock. This channel directs the water towards the powerhouse, which is located at the base of the dam. The force of the moving water is used to spin a turbine, which is connected to a generator situated directly above it.

Once the turbine is set in motion, the generator converts this mechanical energy into electricity. This power is then transmitted away from the facility via long-distance power lines. Finally, the water that has passed through the turbine is discharged into the river downstream, completing the cycle. The entire system is designed to harness the natural flow of water to provide a consistent source of renewable energy.

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Process diagrams

How to write about process diagrams: tips and vocabulary

  • →Say how many stages there are and where the process starts and ends.
  • →Use the passive and sequencers: first, after this, once, finally.
  • →Keep every stage; a missing step costs task achievement.
  • illustrates

    shows or makes clear by using a diagram

  • mechanism

    a system of parts working together in machines

  • continuous

    forming an unbroken whole without any interruption

  • converts

    changes something into a different form or state

  • transmitted

    passed on from one place to another

  • downstream

    situated or moving in the direction of flow

Frequently asked questions

What should the overview say?+

The process describes how potential energy from stored water is converted into electrical energy through a series of mechanical stages.

How many words and how long for IELTS Writing Task 1?+

At least 150 words; 170 to 200 is the safe range. Spend about 20 minutes on it and leave 40 for Task 2, which carries twice the marks.

How is IELTS Writing Task 1 scored?+

On four criteria: task achievement, coherence and cohesion, vocabulary, and grammatical range and accuracy. A clear overview of the main features is what most separates Band 6 from Band 7 and above.

How do I describe process diagrams?+

Say how many stages there are and where the process starts and ends. Use the passive and sequencers: first, after this, once, finally. Keep every stage; a missing step costs task achievement.

Keep practising

More process diagrams

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