How electricity is generated in a hydroelectric power station - Test 3
Cambridge IELTS 14 · Test 3 · Writing Task 1
You should spend about 20 minutes on this task. Write at least 150 words.
Summarise the information by selecting and reporting the main features, and make comparisons where relevant.
https://cdn.cambridgeready.com/images/b373744c56fbcadfb964dafd8fbf54b33a23b45289f320dbda4545a05eea233c.avif
The diagram below shows how electricity is generated in a hydroelectric power station.
Hydroelectric power station
A cross-section diagram of a hydroelectric power station, a two-way cycle between day and night. A river flows into a high-level reservoir held back by a dam. At the foot of the dam an intake (open by day, closed at night) leads into a sloping pipe that runs down to a power station. By day, water flows down the pipe from the high-level reservoir 'to generate electricity': it passes through reversible turbines in the power station, which operate a generator; electricity goes out along power lines to the national grid, and the water continues into a low-level reservoir. At night, the flow reverses: the reversible turbines pump water from the low-level reservoir back up the pipe into the high-level reservoir ('flow of water during pumping (night)'). Key features: the same turbines generate electricity by day and act as pumps at night; water circulates between the two reservoirs; the intake controls the flow.
Available as a free printable PDF worksheet with an optional answer key.