AlpinSolar: construction starts on the largest alpine solar plant in Switzerland

01.06.2021 - Over the next four months, Axpo and IWB will build the largest alpine solar plant in Switzerland at the Muttsee dam. Following construction approval from the local municipality of Glarus Süd, the first components were transported to the dam yesterday. AlpinSolar will generate 3.3 million kilowatt hours of electricity annually, half of which in winter. Supermarket chain Denner has concluded a power purchase agreement for the electricity it produces over a period of 20 years.

The local municipality of Glarus Süd issued the formal construction approval for AlpinSolar last week. Construction work began officially with the transport of the crane via helicopter to the Muttsee dam. During construction, the crane will be required to install the solar panels and the substructure on the Muttsee dam.

As the Muttsee dam cannot be reached by road, the plant components will be brought to the dam by helicopter. Optimal flight times and flight corridors have been coordinated with the municipality to minimise the impact on the environment and the local population as much as possible. The CO₂ footprint created by use of the helicopter will be offset within a few months of the plant’s operation. Over the next four months, a total of 730 tonnes of material will be delivered to Tierfehd, staged there and then transported to the dam by helicopter. The hiking trail that passes over the Muttsee dam will be rerouted due to the construction work. Visits to the construction site are not possible for safety reasons.

Winter power from the dam

Under ideal conditions, the solar plant on the Muttsee dam will feed 2.2 megawatts of electrical output into the grid and is expected to generate 3.3 million kilowatt hours of electricity annually – half of which in winter. This will make it the largest alpine plant in Switzerland. Initiated by Axpo, the project will be implemented in collaboration with IWB, the energy supplier of Basel-Stadt. Through the project, Axpo and IWB are making an important contribution to Switzerland’s energy transformation. Planeco, a subsidiary of IWB, has been commissioned to build the solar plant. Retailer Denner has concluded a 20-year power purchase agreement for the solar electricity generated by the plant.

For more information, go to: www.alpinsolar.ch

About Denner: Denner is Switzerland’s leading discount supermarket with a presence as a local supplier in every rural and urban region of the country – everywhere that customers live and work. Denner offers a comprehensive range of products for everyday requirements at over 820 locations. In 2020, the discounter had more than 5,700 employees. To ensure that this growth does not affect the environment, Denner has set ambitious goals in its sustainability strategy and invests in innovative projects to drive responsible action both internally and externally.

About Axpo: Axpo is Switzerland’s largest producer of renewable energy, as well as an international leader in energy trading and the marketing of solar and wind power. Its 5,000 employees combine experience and expertise with a passion for innovation. Axpo uses state-of-the-art technology to develop innovative energy solutions for its customers in 30 countries in Europe, North America and Asia.

About IWB: IWB is an energy, water, mobility and telecommunications company. It is a committed, competent and reliable supplier to its customers in the Basel region and beyond. IWB is a leading service provider for renewable energies and energy efficiency. The company strives for a 100% renewable power supply that enables climate-friendly, efficient and economical use of energy. IWB already produces more renewable electricity in its plants than is required by its customers in Basel. IWB makes targeted investments in infrastructure and develops new business models.

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