Hydroelectric power stations

There are two main types of hydroelectric power station:

In conventional hydroelectric stations, the water flows from the reservoir to the turbines through a high pressure conduit then it flows out, usuay into a river.

In pumped-storage hydroelectric stations, the water flows from the turbines to a second reservoir. Then it is pumped back up to the higher reservoir and stored for later. These stations are often built in areas where there isn't enough rain of river water to keep the upper reservoir full, so the water must be reused.