Voith Secures Strategic Contract to Supply Pump Turbines for Grimsel 4 Hydropower Project in Switzerland

Contract signing for the new project between Voith and Kraftwerke Oberhasli (KWO).

(IN BRIEF) Voith has secured a contract from Kraftwerke Oberhasli AG to supply and install two 70 MW variable-speed pump turbines and motor generators for the Grimsel 4 pumped storage power plant in Switzerland. The project will enhance energy storage capacity, improve grid stability, and support the integration of renewable energy. This marks the first major new-build collaboration between Voith and KWO, with the contract awarded based on a competitive offer and proven technical design. The development strengthens Voith’s position in the Swiss hydropower market while contributing to the expansion of flexible, carbon-free energy infrastructure.

(PRESS RELEASE) HEIDENHEIM, 10-Apr-2026 — /EuropaWire/ — Voith has been awarded a contract by Kraftwerke Oberhasli AG (KWO) to supply and install key components for the new Grimsel 4 pumped storage power plant in Switzerland, marking a significant step in expanding energy storage capacity in the region.

The project includes the delivery and installation of two variable-speed pump turbines, each with a capacity of 70 megawatts, along with the associated motor generators. These units are designed to enhance both pumping and generation capabilities at the Grimsel site, enabling greater flexibility in energy storage and contributing to grid stability as renewable energy sources continue to grow.

This contract represents the first major new-build collaboration between Voith and KWO, strengthening the partnership between the two companies. The selection of Voith was driven by a competitive proposal and a robust technical concept built on a proven hydraulic design, helping to reduce technical risks and ensure reliable project execution.

Ueli Gasser emphasized that the Grimsel 4 project plays a crucial role in expanding storage capacity and improving system flexibility, highlighting the importance of Voith’s technical solution and constructive collaboration throughout the tender process. Aleksandar Glamoclija noted that the project further strengthens Voith’s presence in the Swiss hydropower sector and reflects the strong working relationship developed during the bidding phase.

The Grimsel 4 development is a key component in supporting the integration of renewable energy by providing flexible storage and balancing services, helping to stabilise the electricity grid during periods of fluctuating supply and demand.

KWO, one of Switzerland’s leading hydropower operators, manages 13 hydroelectric power plants and eight reservoirs, producing between 2,200 and 2,400 gigawatt-hours of electricity annually. The company plays a critical role in delivering carbon-free base-load and peak-load power while ensuring grid reliability across Switzerland and beyond.

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.

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.

About Voith Hydro
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.

Media Contact:

Tamara Lemm
Manager Regional Communications – EMEA
Tel: +49 7321 37 9940

SOURCE: Voith