The study is based on more than 600 system tests, which the power supplier E.ON wants to evaluate together with the Fraunhofer Center for Silicon Photovoltaics CSP and the ZAE Bayern – Bavarian Center for Applied Energy Research. It is already clear: A frequent cause of impairments is improperly laid cables, including cables of the wrong type, which were neither suitable for outdoor use nor for the voltages that occur. An error with hazard potential that can be avoided.

»The E.ON solar professionals were deployed on hundreds of roofs throughout Germany for one and a half years and tested not only smaller systems within the kilowatt range but also large outdoor installation with up to 5 megawatt«, explained Matthias Krieg, head of PV Maintenance/Services at E.ON Energie Deutschland.

E.ON made the extensive results of these tests available for the study in anonymized form. The data provides information on the location and size of the installations, the commissioning, electricity yields produced and the findings of the professionals. The result is a representative cross-section, which on the one hand shows the advantages of installations in perfect condition, and on the other hand also provides information on the extent to which safety-relevant distinctive features and yield losses occur. At the same time, it is also possible to determine whether specific regions, years or module types are particularly affected. »Overall, the evaluation should help to create a stronger awareness for quality management and draw forward-looking attention to issues regarding the maintenance, reliability and life of the installations«, said Matthias Krieg of E.ON.

The Fraunhofer Center for Silicon Photovoltaics CSP is a longstanding provider of support for the power supplier for the quality and reliability assessment of photovoltaic modules and systems. For the study, the research facility in Halle (Saale) is characterizing modules, components and materials. »With our expertise and our research equipment we can combine the material science analysis and mechanical tests on the module, and can take power measurements in the laboratory and in the field, and perform simulations for various stress factors«, is how Dr. Sascha Dietrich, who is responsible for the project at the Fraunhofer CSP, explained the contribution of the Fraunhofer researchers. »The data of this unique survey will help to identify further potential for improvements in photovoltaics.«

The E.ON solar professionals also have long established relations with the ZAE Bayern. In addition to evaluating the installation tests, the aim is to cooperate on a further research project. This purpose of the project is to specifically examine the quality and reliability of photovoltaic components, in order to minimize errors during installation and to reduce or completely avoid risks.