Using waste heat energy from CO₂ cooling units at EDEKA Supermarket

The history of EDEKA Meyers Frischecenter is similar to the history of DK Kälteanlagen. Both successful companies are now in their thirties and are family owned.

1In 1980, Bert Meyer founded a delicatessen store in Pinneberg. By now, the company developed to a medium size food chain with seven locations for example in Hamburg, Pinneberg and on the island of Sylt. Bert Meyer involved his daughter and his son successfully in the company to correspond this positive development. In April 2004, Jörg Meyer overtook a former Intermarché store in the Ölmühlenweg in Hamburg-Wandsbek. With this overtake Jörg Meyer built the biggest supermarket of family Meyer with a sales area of 3,100 sqm.

Since the end of the last year after comprehensive renovation, the EDEKA market Meyer’s shines like new. The new designed sales area provides the customers a sales experience with a multitude of choice:  fresh fish and meat as well as cheese and dairy products. Large investments in the sales area were also mirrored in sustainability improvements to the back of house areas.

Carrier Commercial Refrigeration Germany planned and installed the new CO₂ booster unit including an innovative application of waste heat energy.

DK-Heat Recovery for CO₂ cooling units

Since 2008, DK has been offering systems (maximum operation pressure 130 bar at 150°C) for optimal waste heat utilization from CO₂ cooling plants. DK has already been successful with 600 delivered units and with more than over 2,000 heat exchangers (status as of August 2018).

Two DK storage tanks take care of warming drinking water as well as heating water free for the EDEKA Meyer’s market. The warming of drinking water is carried out directly by double walled internal CO2 heat exchangers in an enamelled storage tank of 450 litres.

Drinking water warming

Because of a sales area of more than 3,000m² and the focus on fresh products, the market needs a high cooling capacity (approx. 160 kW). The chosen concept contains of a tailor made storage tank of 900 mm in diameter, including nine double walled heat exchangers connected by a 1 5/8” K65 pipe.

The heat exchangers can transfer 21 kW waste heat and can produce more than 300l/h for free from 10°C to 60°C.

Heating water

The second storage tank with single walled finned tube heat exchangers directly warms up heating water, without the need of a loading pump. For this purpose, seven heat exchangers are built along the complete height of the storage tank and transfer at a total mass flow of 3806kg/h an effective waste heat capacity of 100 kW in winter.

In summary; the EDEKA “Meyer´s Frischecenter” solved two comprehensive challenges. First the decision to future proof the refrigerant issue by adopting the refrigerant CO₂ as a long time solution. Secondly taking a responsible resource and environmental decision to invest in an energy saving and environment friendly use of waste heat, which will minimise the energy costs and carbon emissions for many years to come