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PhD Position

Topic: Modern planning methodology for solar heating networks and energy efficient district heating


Date of publication: 5 July 2013


Employer and Workplace: Vela Solaris AG, Stadthausstrasse 125, Winterthur, Switzerland. In addition, several weeks of internship at different hosts within the SolNet/Shine network are part of the PhD program.


Research project: The PhD work will be embedded into the applied research and software development activities in conjunction with the commercial planning software Polysun. New Polysun features are developed and a general planning methodology is established. The goal is to provide a powerful and user-friendly tool which supports the planning of district heating networks, as for example the integration of solar energy, and the optimization of energy efficiency. The results of this research project will be disseminated to the broad Polysun user community. Vela Solaris offers support by senior programmers for this task so that the PhD student can focus on the scientific part of this task.


Job description: While today’s functionality of Polysun is restricted to single houses, it is the goal to cover larger and more complex thermal systems. In close collaboration with the software engineers of Vela Solaris the numerical models of the heat demand from district heating systems are implemented. Several heat sources such as solar collectors, geothermal probes, power heat cogeneration as well as the various ways for heat storage are already available at project start. Therefore, the work can focus on the system control and optimization strategy. The Polysun models and the system control strategies are validated and the model parameters are calibrated both with use of existing measurement data and with reference to TRNSYS simulations. For this task, there will be a strong collaboration with other researches within the SHINE network and with collaboration with the leading Universities.



  • Applicants must hold a Master of Science Degree (or equivalent) in Civil Engineering, Mechanical Engineering, Process Engineering, Physics, or equivalent. It must entitle the PhD candidate to start postgraduate studies at the University of Innsbruck (see for more information).
  • Strong interest in software engineering, renewable energy. Programming experience is an advantage but not required. Excellent skills in written and spoken English are indispensable. Communication in German is a clear advantage
  • Other qualities required: team oriented, enthusiastic, innovative and accuracy


Funding: This project is funded by the EU-Project SHINE. The PhD will receive a grant according that covers the cost of living in Switzerland. Furthermore travelling costs and participation at international project meetings and conferences are covered.

Start: December 2013, negotiable.

Application Deadline: 15 September 2013


Additional information: The PhD student will be supervised by Dr. Andreas Witzig (Vela Solaris AG) and Prof. Wolfgang Streicher (University Innsbruck) and is fully integrated into the PhD courses within the SolNet/Shine Network ( )


How to apply: Send application to Andreas Witzig ( or follow the instructions on Solnet


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