
Through introducing compound refrigeration systems with integrated heat pump function REWE Group has further improved its energy efficiency. The compound refrigeration systems use the entire waste heat from a commercial refrigeration installation to heat the store in winter. Up to an outside temperature of zero degrees Celsius no additional room heating is required. The compound refrigeration system is fitted with two additional compressors to ensure that this principle even functions on cold winter days when outside temperatures plunge below zero. These compressors work in winter as heat pumps and in summer function as refrigeration systems.
Thanks to this technology, far less refrigerant is used. It also means that the store requires neither a conventional boiler nor a separated refrigeration system for air-conditioning rooms. Such a compound system enables annual gas consumption to be cut by as much as 80,000 Kilowatt hours by making traditional heating superfluous. Waste heat from refrigerator units is already being used for heating in around 465 REWE Group stores. Approximately 124 stores are already operated without the use of any fossil fuels.