Simulation of a Solar Assisted Combined Heat Pump-Organic Rankine Cycle-System

Stefan Schimpf
Ruhr-Universität Bochum, Thermodynamics, Bochum, Germany

Karsten Uitz
SIMAKA Energie- und Umwelttechnik GmbH, Argenbühl, Germany

Roland Span
Ruhr-Universität Bochum, Thermodynamics, Bochum, Germany

Ladda ner artikelhttp://dx.doi.org/10.3384/ecp110573937

Ingår i: World Renewable Energy Congress - Sweden; 8-13 May; 2011; Linköping; Sweden

Linköping Electronic Conference Proceedings 57:35, s. 3937-3944

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Publicerad: 2011-11-03

ISBN: 978-91-7393-070-3

ISSN: 1650-3686 (tryckt), 1650-3740 (online)


In conventional collector systems for the supply of domestic hot water and space heating the collectors come to a standstill during summer whenever the maximum temperature in the storage tank is reached. The resulting excess heat can be harnessed by a combined heat pump-Organic Rankine Cycle-system. The aim of this work is to simulate such a system in order to determine the optimum operating conditions and impacts on power requirement and cost. For this purpose models for collector; storage tank; heat pump and geothermal heat exchanger are implemented. First results indicate that the isentropic efficiency of the scroll expander has the largest influence on the ORC-revenue. For a system consisting of 12 m² flat-plate collector area with an expansion efficiency of ?s; exp 0.7 = the power requirement for space heating and domestic hot water is reduced by 3.6%; whereas the costs decrease by 42 € or 12.3% respectively compared to a conventional system. The results suggest that an installation is more reasonable in larger dwelling units like hotels; senior citizens’ homes and multiple family dwellings.


Solar Heating; Organic Rankine Cycle; Heat pump


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