Stoosbahn heats an entire hotel

The Stoosbahn advertises that it is the “steepest funicular in the world”. From Schwyz up to the Stoos (1300 meters above sea level), the incline is 110 percent in some cases. The train was only built five years ago and recently it has a new energy concept.

The mountain railway uses the “recuperative energy” that is generated when braking, and the waste heat from the machine room. Both will be converted and supply the new hotel “Stoos-Lodge” with hot water.

Water tanks as heat storage

René Koch is an engineer and ropeway specialist. He explains the principle: “When starting, the train needs energy. As soon as it gets into the steep slope when driving down, it tips over. Then the electric motors give off electricity and we can recover a large part of the energy used.”

Legend: The new hotel “Stoos-Lodge” has 101 rooms. It is right next to the yellow mountain station of the Stoosbahn. srf

The process of recuperation is also used in electric cars, for example. Since the battery is charged when braking. The principle is not new, but the Stoosbahn is different in how efficiently the electricity can be used. Converting electricity to hot water works in a similar way to an immersion heater or kettle.

During this transformation you lose practically no energy.

René Koch: “We heat two water tanks to around 90 degrees. During this conversion, you lose practically no energy.” The two tanks each hold 5000 liters of water and are also heat accumulators. The efficiency is relatively high. The energy gained through braking and the waste heat is 410,000 kilowatt hours. This corresponds to savings of 41,000 liters of heating oil per year.

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Legend: The engine room of the Stoosbahn. Here the waste heat of the drive machine is used and the braking energy is gained. srf/ raphael prince

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Legend: From electricity to hot water: The heating of the water in the tank works according to the principle an immersion heater. srf/ raphael prince

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Legend: The Stoosbahn’s energy is sufficient to heat the hotel and for the hot water in all 101 rooms. srf/ raphael prince

The train was opened in 2017, the hotel Stoos-Lodge will be ready in the next few days. You could already pay attention to energy efficiency during construction. One advantage for optimal use of the electricity generated is certainly the geographic proximity. The distance between train and hotel is short. No energy wasted on the way and the proximity was also an advantage for the construction.

It is a circular economy in a very small space.

Nevertheless: The fact that warm water flows out of the showers of 100 rooms and in the wellness area in the new hotel is contractually regulated. hotel and train are separate companies and the hotel buys the electricity from the train.

Especially in times of high energy prices, this calculation works, says Marcel Neuhaus, Managing Director of Stoos Hotels: “We have the opportunity to get electricity from the Stoosbahn at a reduced price. That’s for us perfect, because it is a circular economy in a very small space. The energy and the money stay in the village.”

Potential for other places

Switzerland is the land of mountain railways. In many places there is a restaurant or a hotel at the mountain station. For Olivier Duvanel, electrical engineer at the Lucerne University of Applied Sciences and Arts, the technology therefore has great potential. “The big advantage: we can use the losses of the drive and save fossil energy. That is a good contribution to the reduction of CO2 emissions.”

The application is not that complicated: “It takes good cooperation between cable car technology and building technology. If that is the case, great projects can be launched.”

Legend: There is often a restaurant or hotel right next to a mountain station in the Swiss mountains. The idea of ​​a common energy concept has potential. srf

On the Stoos, the new hotel welcomes its first guests on December 15th. After several tests, Marcel Neuhaus is confident that everything works and says with a smile: “Nobody has to be cold– on the contrary: our guests can shower a little longer with a clear conscience.”