Summarise the information by selecting and reporting the main features, and make comparisons where relevant.
The illustration demonstrates how sea water is transformed into hydro-electric power to supply our energy needs.
Initially the sun’s rays heat the surface of the sea causing the water to evaporate into clouds which then results in rain. A man-made dam stores this rainwater in a reservoir. With the aid of a valve, the reservoir water completes a cycle as it is channeled through a turbine and pump. In this way, water is re-cycled and the pressure from its circulation produces energy.
The turbine is connected to high voltage cables and once the water energizes the turbine this goes to a transformer station. The station is responsible for distributing the electric power to hospitals, schools, factories and houses via underground cables. This forms the final stage of the process.
To conclude, natural resources (water, sun, rain) in combination with man-made aids (turbine, cables, power station etc) supply us with clean energy using a relatively simple procedure.
Question taken from Official IELTS Practice Materials (2009) p.32