Academic Writing Task 1 · process diagram

The step-by-step process of generating electricity from coal: 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.
  • 185 words
  • Process diagrams
  • Academic
  • 20 minutes

The question

The diagram below shows how coal is used to generate electricity.

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

Coal-fired electricity generation process
  1. 1.Coal storage
  2. 2.Pulverisation
  3. 3.Furnace combustion
  4. 4.Steam generation
  5. 5.Turbine rotation
  6. 6.Electricity generation
  7. 7.Cooling
  8. 8.Transformer voltage adjustment
  9. 9.Distribution via power lines

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 8185 words. Every figure in the answer comes from the chart above.

The provided diagram illustrates the sequential stages involved in the generation of electricity using coal as the primary fuel source. Overall, the process is a closed-loop system that transforms chemical energy into electrical energy through combustion, steam production, and mechanical rotation.

The process begins with coal being stored and then transported to a pulveriser, where it is ground into a fine powder. This pulverised coal is fed into a furnace, where it is burned to produce heat. This thermal energy is used to heat water within a pipe system, converting it into steam. The high-pressure steam is then directed towards a turbine, causing it to rotate.

Following the turbine stage, the mechanical energy generated is transferred to a generator, which produces electricity. This electricity is subsequently passed through a transformer to adjust the voltage before being transmitted across the national grid via power lines. Simultaneously, the steam used to drive the turbine is directed into a cooler, where it is condensed back into water and recycled back into the furnace to repeat the cycle, ensuring the efficient use of resources throughout the power generation process.

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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.
  • sequential

    following a logical order or a set sequence

  • closed-loop

    a system that operates in a continuous cycle

  • subsequently

    happening after something else in a sequence

  • simultaneously

    occurring or operating at the same time

  • transformed

    changed in form, appearance, or structure

  • efficient

    achieving maximum productivity with minimum wasted effort

Frequently asked questions

What should the overview say?+

The process illustrates a multi-stage cycle where coal is converted into thermal energy to drive a turbine, ultimately producing electricity for distribution.

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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