American cities are putting turbines in water pipes to generate clean energy with zero environmental impact. In Portland, water mainly comes from the surrounding mountains. Gravity forces the water down the pipes, spinning the turbines and creating a source of clean energy under the ground. Because gravity is the force that moves the water, no extra energy needs to be used. Riverside, California is also installing turbines in water pipes. They generate enough energy during the day to power the water system itself and at night the turbines keep the street lights on.

Portland has installed turbines in 15 metres of pipes as a trial at a cost of 1.7 million dollars. They generate around 1,100 megawatt-hours of electricity every year. Enough to power about 150 homes and cut back on the use of polluting fossil fuels.

Should Australian cities install turbines in its water pipes too?