Excess river water reduces Swiss hydropower capacity

More water does not necessarily mean more electricity from hydropower plants. © Keystone / Christian Beutler

Switzerland’s overbursting rivers, swollen by excessive rainfall, have resulted in some hydroelectric power plants having to reduce operations.

Nearly 60% of Switzerland’s electricity production is derived from hydropowerExternal link, with 677 plants dotted around the country.

But more water does not necessarily lead to increased power production from this source. Several rivers, such as the Aare, are raging too hard for hydropower plants to cope with.

Six river power plants run by provider BKW have been forced to shut down temporarily, company spokesman Stefan Bütler told Swiss public broadcaster SRF.

“Many systems are running at half capacity. A few are completely switched off. I would estimate that we are currently running at about 40% production,” he said.

The Eglisau hydroelectric power plant on the river Rhine in northwest Switzerland is running at 20% capacity, said operators Axpo.

The problem is threefold: turbines are not designed to cope with such powerful water flow; in some areas flood prevention systems divert excess water away from the normal course of the river; and there is a fear that rivers will pick up debris as they burst their banks, risking damage to turbines.

Still enough energy production

However, there is currently little fear that reduced capacity of hydropower plants will result in electricity shortfalls, according to the Swiss Federal Office for Energy.

Storage and pump storage plants have more than enough capacity to compensate for the reduced operations of plants that run in flowing rivers. These facilities also compensate in winter when rivers are less full, Christian Dupraz, Head of Hydropower at the energy ministry told SWI swissinfo.ch.

While rivers in high spate are causing problems in some parts of Switzerland, this is not the case across the whole country, he added.

“Switzerland exports electricity during the summer months, so while there is currently a reduction in exports there is no shortage of electricity,” Axpo spokesman Nöel Graber told SWI swissinfo.ch.

“Even if the rain continued for weeks, there would be no problem meeting electricity demand.”

The heavy rainfall that has caused disruption in Switzerland and surrounding countries, is forecast to ease over the weekend with sunnier weather expected next week.