Energy Assessment

Energy evaluation of the heat recovery potential on the cooling of cold compressors in restaurants on a university campus

Context and scope

According to current practices, the industrial water used for cooling compressors in restaurant refrigeration cycles is discharged directly with the wastewater. Potentially, the temperature and the flow are high enough to recover heat for the preparation of domestic hot water. It is therefore necessary to conduct an evaluation study on the potential measures aimed at increasing the efficiency of the processes.

Mission objectives and limitations

The purpose of this report is to provide a basis for decision-making to the university’s building operations department regarding the savings potential of compressor cooling systems linked to the refrigeration cycles of campus restaurants. This report includes the installation of the Droople solution at the data collection points, a measurement campaign carried out over several representative weeks, an estimate concerning the heat recovery potential as well as recommendations on the measures to be taken to achieve these savings. This report focuses only on part of the energy processes and aims to establish the order of magnitude of the savings. Therefore, it is in no way intended to replace a general energy audit or technical planning of equipment that could be carried out by the building operations service.

Measurements were made with Droople measuring devices (iFlow), in particular the first versions of the prototypes under development. As a result, Droople declines all responsibility for any errors or inaccuracies related to the results.


There is a real potential for heat recovery which we recommend to exploit. The technical solutions for the implementation of a suitable heat exchanger in terms of dimensioning as well as the necessary investment must be evaluated by the building operations service of the university to obtain product references and prices adapted to the size of the campus.

Audit period


Not valued heat


Cost saving opportunity