Festive inauguration of the Muttsee dam

09.09.2016 - Axpo is one important step further along with the Limmern pumped storage plant (PSP). Today, 9 September 2016, the newly constructed Muttsee dam was christened in a festive ceremony. With its 1054 metres, the dam is the longest in Switzerland. Located at approximately 2500 metres above sea level, it is the highest dam in Europe. The new Muttsee dam is a key element of the new Limmern pumped storage plant. Together with the Canton of Glarus, Axpo has invested CHF 2.1 million in this highly flexible plant. With a pumping and turbine capacity of 1000 MW, the Limmern PSP will make an important contribution to the security of supply in Switzerland.

At the inauguration ceremony on the Muttenalp, the new dam was festively christened by the Glarner minister Josef Kohler with political representatives from the Canton of Glarus in attendance. Axpo CEO Andrew Walo was visibly proud that the project was realised on schedule and on budget, and thanked employees and the partner companies for „their tremendous achievement“. Walo also expressed special thanks to the Canton of Glarus for the generous, continuous support of the project.

The Limmern pumped storage plant is a „once-in-a-century achievement for Axpo. It’s been 26 years since we inaugurated the last dam in Switzerland at the Panix Lake,“ said Andrew Walo. The Limmern PSP is also special owing to the fact that the project was achieved without any opposition: „For us this is proof that is possible to develop good solutions together with residents and environmental organisations if one engages in a true dialogue.“

The Chief Magistrate of the Canton of Glarus, Rolf Widmer, congratulated Axpo on behalf of the Glarus cantonal government. He praised the collaboration between the builders and the public authorities, which remained as exemplary during the construction phase as it was during the planning phase. „The Linthal 2015 project has received wide approval as a model for farsighted planning, taking into account the interests of all stakeholders such as environmental organisations,” said Rolf Widmer. It is the merit of many parties that enabled this spectacular construction project to be realised „so quickly and in such good quality“. 

Construction of the superlative

With 1054 metres, the dam is the longest in Switzerland. Located at approximately 2500 metres above sea level, it is the highest in Europe. It would be possible to build 2200 single-family homes with the concrete used for the construction, and the full reservoir volume of 23 million m3 could fill 9200 Olympic swimming pools.

A total of more than 3000 workers from numerous engineering, construction, subcontracting and specialty companies were active in the mountains, underground or in the valley at Tierfehd. Some 6000 plans were drawn up for the machine and transformer caverns, and the quality assurance reports for the hydraulic steel works fill 870 binders. 

A trump card for Axpo in the long term

The decision to build the Limmern PSP was made during a time when the power price was high and the revenue outlook for these types of power plants with peak energy was optimistic. When the Axpo Board of Directors approved the project in 2009, security of supply was a key motive – and it remains so today, but under completely different market conditions. Hence, it will be difficult to cover the full costs of the plant during the first years of operation. However, the 80-year investment horizon for pumped storage plants is very long term. Axpo is convinced that in the long run it has a trump card in hand with this highly flexible plant that can switch from turbining to pumping in a matter of minutes.

The strong growth of volatile wind and solar energy increasingly results in instabilities in the grid. Therefore, controllable capacity (control energy) in Switzerland and Europe will gain in value. Axpo will offer CO2-free grid and capacity reserves on the markets for control energy and ancillary services. Furthermore, the power will be sold on the options and spot markets (intraday market, where highly flexible plants like Limmern are in demand in view of price fluctuations in quarter-hour intervals dictated by the market. 

All machine groups in operation by mid-2017

When the plug is pulled in a symbolic act, the Muttsee will once again be completely drained from now until mid-September. When the reservoir is empty, the second pressure tunnel will be connected to the works water system and filled with water for the first time during the next reservoir filling. This is a prerequisite
for the commissioning of machine groups 3 and 4. Machine groups 1 and 2 have already been successfully synchronised with the grid and will be generating electricity by the end of 2016. Machine groups 3 and 4 are expected to go into operation in mid-2017.

You will find graphics and photos to download on our website

Facts and Figures:

• CHF 2.1 billion were invested by Krafwerke Linth-Limmern AG, in which Axpo holds an 85 % interest and the Canton of Glarus a 15 % interest
  
• An approximately 10-year period of construction and planning/ground-breaking in 2009
  
• Four reversible pump turbines with a turbine and pumping capacity of 250 MW each
  
• Four rotors weighing 330 tons each were assembled by Alstom in the machine cavern be-cause they could not be transported from the factory to the mountain
  
• Transformers, each weighing about 220 tons, are the heaviest parts that were transported to the mountain
  
• The transport facilities (funicular, construction cableways 1 and 2) moved 3.5 million tons of material up and down the mountain, and transported approximately 1.4 million passengers