Elektrizitätswerk Obwalden (EWO) has launched a preliminary project for a proposed pumped storage power plant between Lake Sarnen and Lake Lungern in Switzerland. This follows a positive feasibility study conducted last year, which evaluated four potential designs and identified the most viable option.
The power plant aims to address growing energy demands by storing and generating electricity during periods of peak demand. It will leverage existing infrastructure from the Lungererseewerk plant, which already supplies electricity to the region using water from Lake Lungern and its tributaries.
EWO’s study highlights three main goals for the project:
- Enhanced energy production: The plant would provide electricity during high-demand periods, particularly when solar and wind sources are insufficient.
- Market optimization: It seeks to capitalize on fluctuations in electricity market prices, improving economic returns.
- Water management flexibility: The project would add options for managing water resources, energy production, and market activity more effectively.
EWO has emphasized the importance of balancing these goals with environmental and community considerations, such as tourism, flood control, and landscape protection.
Preferred design selected by EWO
The preferred design includes a feeder system, a main pump turbine, and an underground pressure pipeline linking Lake Sarnen to the Unteraa power plant. This option was chosen for its technical feasibility, cost efficiency, and ability to integrate with existing infrastructure, reducing resource use. The estimated cost of the project is 56 million francs.
EWO will now engage with authorities, landowners, and stakeholders to refine the project. Environmental studies, geological analysis, and funding options will also be further explored.
An information event scheduled for spring 2025 will provide updates and allow public input on the planned power plant.
