Case studies

Federal ice-skating training center in Oberstdorf cools naturally


SSP Kälteplaner AG


Johnson Controls


Ammonia (NH3)

Refrigerant Capacity:

1915 kW (total)

Heat Capacity:

870 kW
System start-up: April 2012


The community council of Oberstdorf, site of the regional and federal ice-skating training center, has invested in the future of its sports center by installing a new refrigeration plant. This uses the natural refrigerant ammonia and has a cutting-edge control system. It cools two ice rinks and a curling hall. A key objective of the project was to replace the original refrigeration system, installed in 1976, with an ecological and economical solution designed to operate long into the future. The council of Oberstdorf contacted the Allgäu office of SSP Kälteplaner AG to develop the right concept. It was crucial that the new system met requirements in terms of operating costs, plant reliability, investment costs, ecology and sustainability.

Up to 250 athletes practice daily in the ice sports center. It was important that the changeover from existing to new refrigeration plant interfered with the training schedule as little as possible. A target was set to change over to the new refrigeration equipment, a heat pump, and new PLC control system within 14 days.


Experts from SSP Kälteplaner developed an engineering concept using the environmentally friendly ammonia refrigerant and taking into account the different load profiles of the two ice rinks and the curling hall. For the implementation, Johnson Controls Inc. was entrusted with the plant construction. Waste heat generated by the refrigeration system is utilized by a heat recovery system and is also boosted to a higher temperature level using a heat pump. This heat pump is connected to the high-pressure side of the ammonia system. Three screw compressor units were replaced with new, more efficient units. Two of these compressors and the new reciprocating heat pump compressor are equipped with frequency converters and permanent magnet motors. The third screw compressor unit with fixed speed has a motor with the energy efficiency class IE3. Thanks to these measures and an average reduction in condensation temperature of 6 K, energy savings of about 16 percent have been achieved. In order to meet safety standards in the use of natural refrigerants, the new electrical control cabinets are located in a separate switchboard room. By using the latest PLC technology, plant operation could be optimized in order to achieve an additional five percent energy savings. These measurements made it is possible to put into practice a more environmentally friendly cooling of the ice sports center and – on top of everything – to save a lot of energy.

Technical data:

Type of facility:

Cooling of ice sports center


Ammonia (NH3)

Refrigeration volume:

12.000 kg

Condensation temperature:

From +32 °C to +20°C

Evaporation temperature:


Detlef Lukas

SSP Kälteplaner AG

Betriebsstätte Gewerbestr. 8

87787 Wolfertschwenden / Germany

Tel +49-(0)8334-259708 0, Fax +49-(0)8334 259708 23