COOLSAN - refrigeration concepts for office and administrative buildings retrofit

Technologies to enhance comfort and minimise energy requirements for air conditioning in existing office and administrative buildings. Possibilities to reduce the cooling loads and strategies for the use of passive cooling systems.

Content Description




The problem of "air-conditioning" respectively the creation of comfortable temperatures in the workplace still has to be solved and not just in terms of the construction of new office buildings but rather this is also a challenge for existing buildings. The increased use of EDP and office equipment is the main reason why room temperatures have increased enormously in existing office and administrative buildings in the last ten years which frequently leads to the comfort levels being surpassed and to a reduction in the productivity of the co-workers. Since, however, personnel costs represent the major cost factor in the service sector, employers try to keep productivity as high as possible.

Usually this is done by investing in conventional compression refrigeration plants (decentral or central). This amounts in an enormous energy requirement which is much higher than by comparison the requirement for heat. This aspect shows that there has to be another focus in office buildings thank in residential buildings when it comes to sanitation of a lasting nature.

The goal of the present project is to minimise the energy requirements to achieve and maintain standardised levels of comfort with innovative retrofit concepts (temperature, air quality, moisture and light conditions) in existing office buildings. In this respect the following questions will be dealt with:

  • How can comfort be created in existing office buildings - without using energy-intensive compression refrigeration plants?
  • How can the energy requirements and operating costs of office and administrative buildings be reduced when compression refrigeration plants are already installed?

Comprehensive replies to these questions and the preparation of the implementation process of two refrigeration "sample retrofits" is a declared goal of the project.

The project will be organised in the following sections:

  • Detailed stock-taking of typical Austrian office and administration buildings with a refrigeration-technical retrofit requirement.
  • Selection and modelling of two office buildings with a high potential for refurbishment (modelling is performed in the dynamic simulation environment TRNSYS).
  • Definition and simulation of measures to minimise the energy requirements of existing office buildings (reduction of loads, use of environmental energies, systems for the distribution and release of cold, etc.).
  • Evaluation of measures in accordance with criteria for comfortableness, ecology, economy and the technical feasibility. Preparation of "case studies" and catalogues of measures
  • Introduction of the concrete implementation process for the two "sample retrofits", dissemination of project results (planning workshop, etc.)

Project Partners

Project manager

Ing. Christian Fink
Institut für Nachhaltige Technologien


  • Ao Univ.-Prof. Wolfgang Streicher, Institut für Wärmetechnik, TU Graz
  • Ing. Theodor Christomannos, Allgemeine Immobilien-Verwaltungs-GesmbH
  • Ing. Günter Hofmann, BIG Bundesimmobiliengesellschaft mbH
  • Ing. Johannes Ott, IMMORENT AG
  • Ing. Knoblechner Maximilian, IMV Immobilien Management und Verwaltung GmbH


Arbeitsgemeinschaft ERNEUERBARE ENERGIE
Institut für Nachhaltige Technologien
Ing. Christian Fink
Feldgasse 19
8200 Gleisdorf,
Tel.: +43 (3112) 5886 - 14
Fax: +43 (3112) 5886 - 18