Study on the Yield of Photovoltaic Systems in Germany

Yield Studies

Yield Map 2018
Distribution of the specific yield of PV roof-top systems in Germany in 2018

Due to the large number of PV systems erected in Germany in various size categories in recent years, the need for reliable key figures for yield valuation has increased. Owners and operators of photovoltaic systems need reference values in order to evaluate the annual and monthly electricity production of their systems, so that conclusions can be drawn about the quality of the PV system. Only systems that are built to a high standard of quality during the planning and construction phases and that have been continuously serviced and maintained since commissioning can fully exploit their technical potential. For investors and operators of photovoltaic systems, the long-term operating phase therefore focuses on the question of whether their PV system achieves the maximum possible energy yield or whether there has been a loss of yield due to technical faults.

For this reason, we have initiated this yield study in order to provide investors and operators of photovoltaic systems with a solid basis for comparing and analysing the energy yields of their PV systems.

The yield study is available for download for the following calendar years:

Performance of roof-top PV systems in Germany from 2012 to 2018. Solar Energy 194 (2019) 128–135

Yield study PV roof-top systems 2018 (in German)

⤓ Yield study PV roof-top systems 2017 (in German)

⤓ Yield study PV roof-top systems 2016 (in German)

⤓ Yield study PV roof-top systems 2015 (in German)

⤓ Yield study PV roof-top systems 2014 (in German)

⤓ Yield study PV systems 2013 (in German)

⤓ Yield study PV systems 2012 (in German)

The algorithm used in the yield study for multi-level data cleansing is described in the following publication:

H. te Heesen, V. Herbort. Development of an Algorithm to Analyze the Yield of Photovoltaic Systems. Renewable Energy. Volume 87, Part 2, March 2016, Pages 1016-1022. DOI: 10.1016/j.renene.2015.07.058

If you have any questions or suggestions regarding the yield study, please contact us by e-mail (h.teheesen(at)

Scripts for sun exposure

The following scripts are available to download the solar radiation into the horizontal plane via the CAMS Radiation Service and to convert it into the inclined module plane:

Jupyter notebook file with complete documentation

⤓ Shell script for exporting CAMS irradiation data to a CSV file

⤓ Python script for importing irradiation data from a CAMS CSV file

⤓ Exemplary CAMS CSV file

⤓ Python script to convert the irradiation into the inclined plane

Project and thesis work

As part of the research on yield data analysis of photovoltaic systems, there are ongoing topics for project and thesis work.


  • Definition of quality indicators
  • Analysis of the configuration of the PV systems
  • Statistical investigation of configuration errors
  • Development of algorithms for automatic error correction

If you are interested in joining the project, please send a mail to Prof. te Heesen.


Prof. Dr. Henrik te Heesen
Prof. Dr. Henrik te Heesen
Professor FB Umweltplanung/-technik - FR Maschinenbau


+49 6782 17-1908


Birkenfeld | Building 9925 | Room 12


Mittwoch/Wednesday, 08:30-09:30 h


Trier University of Applied Sciences, Environmental Campus Birkenfeld
Institut for Operations and Technology Management (IBT)
Campusallee 9925
55768 Hoppstädten-Weiersbach

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