Hydropower

Hydropower: electricity generation using water

Two things are necessary to utilise hydropower: a ‘head’ (or height difference) in the river and moving water. A hydropower station, just like old watermills, benefits from the head in the river. The falling and flowing water sets the turbine in motion. This rotating movement is used to generate electricity with the aid of the generator. 

The Netherlands is a water-rich country with plenty of flowing water, but the gradient of descent in the rivers is fairly gradual. The dams in the Maas and Rhine have a drop of 4 meters at most. This explains why hydropower can, at best, make only a modest contribution to the energy supply in the Netherlands. 

Hydropower stations at Maurik, Hagestein & Alphen aan de Maas

Dams have been built at Hagestein and Amerongen in the Lower Rhine and at various locations in the Maas to ensure there is sufficient water for shipping to continue when the water supply is low. The ships can then pass the dams via the sluices. The difference in water levels is used by hydropower stations to produce electricity. 

The hydropower station at Maurik comprises four identical hydropower installations standing side by side. Each installation consists of a flow channel with diameters varying from 4 to 10 metres. The turbine, which looks like a small submarine, is located in the flow channel. 

The water flows onto the turbine at high speed (12 metres/second), setting the blades at the rear in motion. The shaft of the blades enters the turbine housing where a gearbox accelerates the relatively slow moving blades(78 revolutions/minute) to a speed of 750 revolutions per minute. 

At this speed the generator (dynamo) can produce electricity with great efficiency. Every generator has a capacity of 2500 kWe. On average the four generators produce 25 million kWh per year, sufficient to power over 8000 households. 

Environment-friendly

During the construction of the station, the immediate surroundings and the local environment were taken into account. The station is entirely built below ground and below water, thus leaving the surroundings intact and causing no noise nuisance. 

Fish-friendly

The power station is equipped with fish-friendly turbines and fish ladders that enable the fish to swim upstream without obstruction. An additional advantage is that floating waste is caught in grates. In this way, the power stations help to keep the river clean.