Supplying and Transporting Hydropower to your Home

A river flows all the time but electricity customers need more energy as certain times of the day.

During peak demand, like hot summer afternoons and cold winter evenings, more water is allowed to flow through dams and their turbines. When there is less need for electricity, the water is allowed to build up again. In this way, a dammed reservoir behaves like a constantly charging battery.
As is the case for other energy sources, hydroelectric energy needs to be transported from remote locations to city centers where it is needed. The transportation of electricity from dams requires an efficient distribution grid.

Because hydroelectric energy needs to travel great distances, hydropower did not become widely used until the technology was invented to transmit electricity over distance.