2026-04-09 Voith awarded contract for Grimsel 4 pumped storage project in Switzerland
- Voith to supply and install two variable-speed pump turbines and motor generators
- Competitive offer and technical concept were key factors in securing the order
- Project marks first major new-build collaboration with KWO and strengthens Voith’s footprint in the Swiss hydropower market
Contract signing for the new project between Voith and Kraftwerke Oberhasli (KWO).
Heidenheim, Germany, April 9, 2026. Voith has been awarded the contract by Kraftwerke Oberhasli AG (KWO) to equip the new Grimsel 4 pumped storage power plant in Switzerland. The scope includes the supply and installation of two variable-speed pump turbines, each with a capacity of 70 MW, including associated motor generators. The units will increase pumping and generation capacity at the Grimsel site and support the integration of renewable energy by providing flexible storage and grid-stabilization services.
The project marks the first major new-build contract awarded to Voith by KWO and represents an important milestone in the collaboration between the two companies. A key factor in securing the order was Voith’s competitive offer, as well as a technical concept based on a tested and qualified hydraulic design, which reduces technical risks and supports reliable project execution.
Tamara Lemm
Manager Regional Communications - EMEA
t +49 7321 37 9940
With Grimsel 4, Voith further strengthens its footprint in the Swiss hydropower market and contributes to the expansion of flexible energy storage capacity in the region.
About Kraftwerke Oberhasli AG
Kraftwerke Oberhasli AG (KWO) is one of Switzerland’s leading hydropower companies. Since its founding in 1925, KWO has been efficiently generating electricity from renewable energy sources for over one million people in Switzerland and abroad. With 13 hydroelectric power plants and eight reservoirs, the KWO Grimsel Power division produces between 2,200 and 2,400 gigawatt-hours of electrical energy annually. This is CO2-free base-load and peak-load power. In addition, KWO ensures a secure and reliable electricity supply through energy production and grid control. As a service provider in the electricity sector, KWO helps prevent grid failures and thus potentially severe economic damage in Switzerland and Europe.
Since its founding, Kraftwerke Oberhasli AG (KWO) has been 50% owned by BKW Energie AG. The remaining 50% is split equally among Industrielle Werke Basel (IWB), Energie Wasser Bern (ewb), and the City of Zurich’s electricity utility (ewz), each holding a 16.6% stake.
About the company
The Voith Group is a global technology company. With its broad portfolio of systems, products, services and digital applications, Voith sets standards in the markets of energy, paper, raw materials and transport & automotive. Founded in 1867, the company today has around 21,000 employees, sales of € 4.9 billion and locations in over 60 countries worldwide and is thus one of the larger family-owned companies in Europe.
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The Group Division Voith Hydro is part of the Voith Group and a leading full-line supplier as well as trusted partner for equipping hydropower plants. Voith develops customized, long-term solutions and services for large and small hydro plants all over the world. Its portfolio of products and services covers the entire life cycle and all major components for large and small hydro plants, from generators, turbines, pumps and automation systems, right through to spare parts, maintenance and training services, and digital solutions for intelligent hydropower.
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