
Refrigerants are not all the same. To quickly and effectively cut climate-relevant emissions, REWE Group has carried out refrigerant tests in its stores and warehouses, to determine if they are both environmentally friendly and cost effective. The loss of refrigerants can never be completely avoided. A leak in the cooling line can happen quickly as the result of improper use or wear. At the beginning of the 1990s, experts found out that refrigerants with CFCs such as R12, R22 and R502 significantly contribute to the greenhouse effect, so these refrigerants were banned. R12 and R502 had to be replaced by refrigerants without the risk of depleting the ozone layer. R22 was banned in new units in 2000, but may still be used in existing systems until the end of 2014.
After R22 was banned, new refrigerants came onto the market, including R134a and R404A. Despite higher investment costs, REWE Group relies on the climate-friendly R134a in many areas, as its greenhouse potential amounts to 1,300 in comparison to 3,784 for R404A. In addition, industry and commerce also need to implement other more climate-friendly refrigerants. That is why REWE Group is currently testing CO2 in the deep freezing systems at about ten supermarkets.
The advantages speak for themselves: only CO2 refrigerants do not reduce the ozone layer, have a negligible greenhouse effect, are chemically inactive, non-inflammable and non-toxic. Furthermore, CO2 is inexpensive and does not have to be recovered and disposed of. This is coupled with its outstanding cooling performance, which is five to eight times that of R22. In the case of positive test results, the company considers to convert the deep freezing sections of further stores to CO2. REWE Group also uses the climate-friendlier ammonia for freezing for large-scale refrigeration systems in its central warehouses. The less climate-damaging refrigerants propane and butane are also used as a standard in around 10,000 deep freezers at REWE and PENY stores, 8,500 of which are in Germany.