The last instance in a proposed building efficiency chain How we use excess heat effectively elsewhere. And what happens, when our customers are satisfied?

Efficiency and sustainability are increasingly important requirements in building design. Not only because these form the basis of many image-building certifications, but also because the consequential cost reductions represent an added value for the end user and, ultimately, more comfort for the people in and around the object.

A structural revitalisation for an increased efficiency

The Migros cooperative's Zurich project "Santer" is a pioneer for efficient heat recovery in their building design. Recently, the Zurich area headquarters have undergone structural revitalisation. As part of this, the refrigeration system in the milk and meat distribution cooling zones has been fully refurbished. The aim was to remove the heat and simultaneously use it elsewhere. To do this, the heat is first re-used by a heat pump system, to produce hot water to supply the heating or defrosting of the installed cooling air cooler, for example. If no additional heat is required at this point, six CABERO recoolers are used to guarantee the required cooling capacity.

The operation of a heat exchanger

A fundamental element of the recooler is the heat exchanger block, which is made up of parallel fins. Tubes pass through these fins, that run the refrigerant - in this case, a water-glycol mixture - through the heat exchanger block. Fans draw ambient air into the counter current flow through the fins, thus ensuring that heat is extracted from the water-glycol mixture. The medium is discharged from the cooler at a significantly lower temperature

Higher rotational fan speeds the increase cooling performance. By spraying or wetting the fins in additional adiabatic systems, the cooling capacity can be further increased, or the same cooling performance can be obtained at higher ambient temperatures.

From the planning stage, through to the application: A perfect selection of devices

Four dry heat exchangers and two adiabatic dry coolers were installed throughout the plant to absorb temperature peaks, particularly in summer time, and to remove the heat when not needed. But here we have also thought of efficiency: Economic EC fans produce more air power, with lower power consumption and less noise. The built-in gold paint flakes in the adiabatic coolers are resistant to crevice corrosion and thus provide greater durability.

The special RAL 9006 white aluminium colour is adapted to the façade of the building, and thus fits perfectly into the overall optical appearance. In order not to interfere with the busy delivery centre business, the delivery of the equipment was planned for a Saturday. Migros and the planners were invited to the CABERO works in Hungary, to carry out a work site inspection. The two nearby cities Kaposvar and Mágocs include company manufacturing facilities , where it is planned to implement individual solutions, tailored exactly according to the requirements of the operators. Here, the two works complement each other perfectly. While one has existed for several generations and works with long-term employees and their experience, the other stands for youthful leaders for innovation and modernity. The strategic mix ensures that both sides learn from and share with each other. Experience on one hand - innovation on the other.

Information about the project: Michael Bruhn, bruhn@cabero.de, +49 8144 20 400 142