Migros

Since mid of July 2017 Migros store Kreuzplatz in Zurich offers a temporary shop to its customers. Meanwhile, the old store is being taken down and rebuilt during the next two years. Despite the temporary purpose, Migros opted for a high sustainability within realisation. On one hand, the building qualifies for Minergie-standard and on the other hand, it is being heated, air-conditioned and food and beverages are being chilled by the first „eCO2cube“-installation. The new eCO2cube is not only eco-friendly, cost-effective and quickly installed, but it allows also for a flexible layout.

On a sales area of approx. 400 sqm, customers can expect a high product variety. Round about 40 meters of medium and low temperature cabinets cover every customer’s needs. The waste heat, produced by food and beverage refrigeration, is used for heating. The heat is being distributed through fan coil units, as needed, to the different areas in the building. The new method, distributing the heat through a CO2 circulation is promising and cost-saving, as the amount of components can be reduced to a minimum and heat or cold can be dispensed efficiently to several areas. The same fan coil units can be used for heating and AC. As with conventional installations, waste heat is being disposed through a gas cooler. Should waste heat from refrigeration not be enough, there is the possibility to feed the building with additional heat through one or several heat pump compressors of the very same unit. As this temporary store will be used for two years and, afterwards, will be taken down again, the complete eCO2cube has been built in a transportable enclosure. The gas cooler is attached directly to the enclosure. This allows to store the installation temporarily and to install it again on a new site. The compact construction has another advantage: there is no necessity of an additional compressor room. Thanks to an optimised sound insulation, the installation can be run on the roof in the middle of the city of Zurich.

The installation is based on a conventional CO2 booster, which is used to chill food and beverages. In order to accomplish a comfortable climate in the building, there is the possibility for AC and heating by means of heat recovery. Should waste-heat from the MT and LT-refrigeration not match the demand in wintertime, additional heat can be gained from the outside air by means of an evaporator, integrated in the gascooler. The manner in which heat and cold are being distributed in to the building depends on the customer’s preference: through a water-grid, through air or straight with the CO2 of the refrigeration unit via the fan coil units placed in the building. Even a combination of all three possibilities is feasible. The advantages of the heating or AC via the fan coil units are low investment costs and very little heat- or coldwaste. In the picture of the CO2 booster system, there are five of six compressors. Regardless of the heat and cold distribution options, there are variable layout possibilities of the installation itself. If conventionally in a compressor room or compactly packed in a weather proof enclosure, both options are viable. Thanks to the sound-proof insulation of the unit enclosure, no noise can be heard even at full load operation. If needed, the gas cooler can be attached to the enclosure and become one single element, which makes the concept even more compact and flexible.

Client
Migros

Area
Retail

Location
Zurich Kreuzplatz (CH)

Cooling capacity
40 kW

Refrigerant
CO2

Technology
eCO2cube

Refrigeration system
CO2-booster refrigeration

Planning performance
eCO2cube System

Efficency increase

Reduced energy consumption

Conception

In this project, Frigo-Consulting was responsible in the following: