Department of Economic Development

Run-of-the-river power station
It is driven by the natural flow of river. When the flowing water is affluent, the electricity generated can reach the total capacity; while the flowing water is insufficient, the electricity generated might below one-third of total capacity. If the water flow is larger than the demand for generating, the excessive water cannot be utilized or stored so that we have to give it up. So the output cannot match the load demand of power system.

Power station with retention basin
The principle of flowing water utilizing is the largely same as run-of-the-river power station, but the tank of power station with retention basin is bigger. When the water storage matches well with capacity of the tank, the power station can fully operate for several hours. If the quantity of flowing water is over capacity of the tank, the excessive water will be useless. In order to cope with the peak load of power demand, the quantity of water storage is very important. The retention basin can be used to adjust the gap between the quantity of water demand of power station and the quantity of naturally flowing water, to match the peak load of electricity system.

Power station with reservoir
The water storage of reservoir is large enough to cover the flood volume of a season or a year to supply the power station to match with the loading demand of electricity system. The operation of power station with reservoir doesn't vary with the quantity of flowing water, but with the loading demand of electricity system.