Refrigeration Technology

Main goal of the described research plan of comprehensive university Essen is the development of a Stirling refrigeration equipment for the cold supply at temperatures between 50 and 20°C. Because of the statutory prohibition of the refrigerating agent R22 since 2000 there is a requirement for alternative refrigerating agents or generation methods for different fields of refrigeration engineering. The project is financed by federal funds by the project agency Jülich PTJ.

The project’s goal is the combined use of high capacity vacuum tube collectors for hot water generation which then is utilized as thermal drive of an adsorptive refrigeration unit producing cold water for climate control/ air conditioning. The project receives federal funding from PTJ – the Project Management Organization Jülich.

The project of the „Ingenieurbüro Hans-Jürgen Niemeyer“ aims at testing a new method for the air conditioning of buildings with a combined adsorption refrigeration unit. The required heat for running the cooling unit is provided by solar vacuum tube collectors. The project receives federal funding from PTJ – the Project Management Organization Jülich.

The demonstration plant uses 22% less primary energy than a cooling system based on electrically powered chillers. In the summer fresh air is dehumidified with a sorption wheel and waste heat from a cogeneration unit and then cooled with underground air by means of geothermal probes.

The air conditioning system developed under the project combines indirect evaporative cooling with a process which uses salt solutions to dehumidify the air. This energy-efficient method enables the exploitation of thermal solar energy.

The already completed project was carried out by the „Bayerisches Zentrum für The already completed project was carried out by the „Bayerisches Zentrum für Angewandte Energieforschung e.V. (ZAE)“ and resulted in the construction of a heat driven combined heat pump and refrigeration unit with considerably higher heat ratio signifying a better utilisation of fuel compared to present common machinery. The project receives federal funding from PTJ – the Project Management Organization Jülich.

The new compression chiller uses only half as much electricity as a conventional refrigeration unit. At the heart of the unit is a hermetically sealed CO2 compressor, which uses carbon dioxide as an environmentally friendly refrigerant.