Energy storage power station of Zurich Public Transport Group Switzerland

One important pillar of this strategy is the further development of electricity storage capacity in Switzerland. In the next years, three large-scale pumped hydro storage power plants will be connected to the grid. The first, the Limmern pumped storage plant (1 GW), should become operational in 2016.

Despite the government's objectives defined in the Energy Strategy 2050, there is currently no direct support via subsidy for pumped storage operators in Switzerland.

In the past, a total of 14, mostly small sized pumped hydro storage plants, were built, the last of which was commissioned in 1990. However, the combined capacity of these plants only amounts to 1380 MW contributing to approximately 4.4% of the total electricity produced in Switzerland.

The pumped storage plants are almost entirely owned by state controlled companies. More recently, ABB together with the Zurich power company EKZ has installed a 1 MW power battery storage solution with a capacity of 250 kWh in Dietikon, located in the canton of Zurich.

Hydropower plays an essential role in the Swiss electricity supply. In fact, over half of the country's electricity is generated by hydropower. Therefore it is not surprising that electricity has been traditionally stored in pumped storage power plants.

Further, the introduction of a cost-covering fee for feed-in to the electricity grid, in order to subsidise new renewable energy sources in Switzerland, disadvantaged traditional hydro electricity producers. As a result, high prices during peak load times dropped, which substantially lowered the revenue stream of pumped storage plants.