Solar assisted heat units in multi-family houses

Daniel Eggert, Dipl-Ing. (FH)
Tel.: +49 (0)5151-999 522

Hardware-in-the-loop test rig with central heat unit
Chart of the functioning of the hardware-in-the-loop test rig
Experimental and theoretical evaluation of the dynamic behaviour of solar assisted heat units including modelling, annual simulation and cost analysis

For multi-family houses the collaborative project will investigate the diverse hydraulics relevant for practice of solar collector fields with heat store(s), heat generator(s) and consumer circuits for space heating, domestic hot water and circulation in heat units with large solar combi-systems. Together with the associated control functions and their hydraulic integration these hydraulics shall be evaluated according to function, energy and cost parameters.

After the classification of typical hydraulic concepts and their algorithms, simulation models for heat units are created and matched. The subsequent execution of system simulation studies allows the identification of the determining parameters for the possibility of optimisation. Industrial companies provide heat units to be tested up to 60 kW heating capacity. These heat units will be investigated in customised hardware-in-the-loop tests of the project partners. Optimised system concepts should be derived from the outcome of the theoretical and practical studies for these heat units in multi-family houses.

The aim is that standardized industrial solutions can be recommended and that concept errors resulting in a loss of yield and efficiency, as they often occur in individually conducted heating systems, may be avoided in order to strengthen the recently weak market of solar supply for multi-family houses.

Final workshop: solar assisted heat units in multi-family houses

On 27 February the ISFH together with the Düsseldorf University of Applied Sciences invited to a project workshop with the following contents.

Program sequence:

1. welcome, presentation of the project
2. classification of solar heating plants and market research
3. hardware-in-the-loop investigations – methodology, boundary conditions, functional system analysis and simulation validation
4. evaluation of solar heat units by energy and costs to identify a best-practice solution
5. guided tour through laboratory and test stand
6. energetic and economic optimization potential of the best-practice concept
7. recommendations for good solar design
8. summary
9. practical example: large apartment building with solar energy system in Düsseldorf
Afterwards: Guided tour through a large apartment building with solar thermal system

The final report of the research project will be published in May.

Project partner

Industry cooperation

Logo Solvis


01.09.2014 – 28.02.2018

Final report

The final report of the project can be found here!


The project ‘Solar-assisted heat units in multi-family houses – Experimental evaluation of the dynamic behaviour of solar assisted heat units including modelling, annual simulation and cost analysis’ was funded by the German Federal Ministry for Economic Affairs and Energy under the promotional reference 03ET1212B.

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