France: une patinoire avec un système R134a/CO2 en cascade

La patinoire de l'Alpe d'Huez a récemment été complétement rénovée en remplaçant l'ancien système frigorifique au CO2 par un système en cascade HFC134a/CO2.
In the French Alps, the Alpe d’Huez ice rink has recently completely renovation, replacing the former HCFC-22 refrigeration system by an HFC-134a/CO2 cascade system.

The ice rink, situated at 1,850 metres, has the peculiarity of being uncovered and runs also in summer. The slab is installed on top of a parking lot. Ammonia could not be used, due to the proximity of habitations and vacation homes.

Therefore CO2 has the advantage of allowing a steep temperature decrease, able to compensate for increased heat contribution.

The new system is designed with a first stage delivering 800kW with 400kg of HFC-134a, and the second stage delivering 600kW with 6 tonnes of CO2 as refrigerant.

Energy from the high pressure circuit condensation is recovered and supplies heat to three exchangers installed in the parking lot to prevent freezing and one exchanger installed in a snow pit, where snow from the rink track surfacing melts.