Academic Writing Task 1 · process diagram

The process of generating electricity from coal using gasification technology: 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.
  • 186 words
  • Process diagrams
  • Academic
  • 20 minutes

The question

The diagram below shows how one type of coal is used to produce electricity.

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

Coal-to-Electricity Production Process
  1. 1.Coal extraction
  2. 2.Crushing
  3. 3.Transportation
  4. 4.Gasification
  5. 5.Cooling
  6. 6.Cleaning
  7. 7.Gas power plant generation
  8. 8.Electricity distribution

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 8186 words. Every figure in the answer comes from the chart above.

The provided diagram illustrates the industrial process of converting coal into electricity. Overall, the procedure is a linear sequence that begins with raw material preparation and culminates in power distribution, involving several intermediate stages of chemical and thermal conversion.

Initially, coal is extracted and processed through a crusher to reduce its size. Once crushed, the coal is transported to a gasifier. During this gasification stage, heat is produced as a by-product. The resulting gas is then directed to a cooling unit, where further waste heat is released. Following the cooling phase, the gas undergoes a cleaning process to ensure it is suitable for power generation.

In the final stages, the cleaned gas is fed into a gas power plant. This facility converts the gas into electricity, which is then distributed to industrial consumers and the national power grid. Similar to the gasification and cooling stages, the power plant also emits waste heat as a secondary output. The entire cycle highlights the complexity of coal-based energy production, emphasizing both the primary objective of electricity generation and the inevitable release of thermal energy throughout the various conversion steps.

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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.
  • culminates

    reaches a climax or the final stage

  • intermediate

    coming between two things in time or order

  • by-product

    an incidental or secondary product made during manufacturing

  • linear

    arranged in or extending along a straight line

  • conversion

    the process of changing something into a different form

  • distributed

    shared out or spread over an area

Frequently asked questions

What should the overview say?+

The process involves a multi-stage transformation of coal into electricity, characterized by several industrial conversion phases and the generation of by-products such as waste heat.

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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