Band 9: You should spend about 20 minutes on this task. 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. You should write at least 150 words.

The diagram illustrates how electricity is produced from coal through a gasification process.

Overall, the process consists of several stages, beginning with coal extraction and crushing, followed by gasification and cleaning, and ending with electricity generation in a gas power plant. Waste heat is produced at different stages of the process.

Initially, coal is mined and then transferred to a crusher, where it is broken into smaller pieces. The crushed coal is transported to a gasifier, where heat is applied to convert it into gas. This gas then moves upward to a cooling stage, during which waste heat is released.

After cooling, the gas passes through a cleaning process to remove impurities before being used further. The cleaned gas is then supplied to a gas power plant, where it is burned to generate electricity. During this stage, additional waste heat is produced.

Finally, the electricity generated is transmitted through power lines to industrial facilities and households. Compared with the early stages, which focus on coal preparation and gas production, the final stage concentrates on electricity generation and distribution.