Academic Writing Task 1 · process diagram

The process of generating electricity using a geothermal power plant: 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.
  • 176 words
  • Process diagrams
  • Academic
  • 20 minutes

The question

The process below shows how electricity is generated with the help of water.

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

Geothermal power plant electricity generation process
  1. 1.Cold water is stored at the surface
  2. 2.Cold water is pumped down a 4.5 km injection well
  3. 3.Water travels through the geothermal zone of hot rocks
  4. 4.Hot water is pumped up through the production well
  5. 5.Steam is produced and directed into a condenser
  6. 6.Steam powers a turbine which drives a generator to produce electricity

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 8176 words. Every figure in the answer comes from the chart above.

The provided diagram illustrates the various stages involved in generating electricity through a geothermal power plant. Overall, the process is a continuous cycle that relies on the thermal energy of underground rocks to convert cold water into steam, which subsequently drives a turbine to produce electrical power.

Initially, cold water is stored at the surface before being pumped down into the earth. This water travels through an injection well to a depth of 4.5 kilometres. Upon reaching the geothermal zone, the water is heated by the surrounding hot rocks. Once heated, the water is then pumped back up to the surface through a production well.

In the final stages, the hot water is converted into steam, which is directed into a condenser. This steam provides the necessary energy to power a turbine. The turbine is connected to a generator, which is activated by the turbine's rotation to produce electricity. This electricity is then transmitted via power lines for distribution. The entire system functions as a cyclical mechanism, utilising the earth's natural heat to generate sustainable 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

  • subsequently

    happening after something else in a sequence

  • utilising

    making practical and effective use of something

  • cyclical

    occurring in a series of repeating stages

  • subsequently

    happening after something else in a sequence

  • consequently

    as a result or effect of something

Frequently asked questions

What should the overview say?+

The process illustrates a closed-loop system where cold water is heated by underground geothermal energy to produce steam, which is then converted into electricity.

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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