Innovative Solutions for Enhancing Rooftop PV Efficiency in Europe’s Renewable Energy Push

Renewable energy goals in Europe require more renewable energy deployment. Looking into the PV market in Europe, rooftop installations dominated other applications with about 60% of the market share in 2022. Germany as the biggest market with respect to total installation capacity, had over 42 GW of PV on rooftops by the end of 2021. The Netherlands, as the country with highest installation capacity per capita has over 80% of the installations on small rooftops.

One of the biggest challenges for PV modules on the rooftops is partial shading due to obstacles such as trees, chimneys, or parapets. Nearby structures and snow during the winter are also a frequent cause of partial shading. Partial shading leads to a significant power loss in module level and it leads to a mismatch in module level but also a mismatch with other modules connected in string. The power loss due to partial shading is highly dependent on the module design, shading pattern, and shading orientation.

Power optimizers can optimize the losses from mismatch, but they cannot save the affected string or PV module and they increase the investment volume. Furthermore, electronic devices are shown to have a lower lifetime compared to passive components like PV modules.

AESOLAR developed a shade-resistant PV module with integrated bypass diodes for each individual solar cells. The module can produce up to 80% more energy under partial shading conditions [1]. The module utilizes full-size solar cells for the design and the module is independent from shading orientation. The module has been awarded by PV Magazine, the top innovation award [2].

AESOLAR, in collaboration with Fraunhofer Center for Silicon Photovoltaics develops a new generation of shade-resistant PV modules with half-cut cells. The collaboration is under SEGMENTPV research project funded by the Federal Ministry of Economic affairs and climate action (BMWK). The project is started in May 2023 and takes two years of research work. “Within the project, module components, designs and prototypes created by AESOLAR will be tested by Fraunhofer CSP to achieve a higher energy yield, better shading tolerance and superb reliability for an innovative product which tackles one of the biggest challenges of rooftop PV” says Dr. Hamed Hanifi, Director of Research and Development of AESOLAR and the coordinator of the SEGMENTPV project.

[1] Hanifi et al, “A novel electrical approach to protect PV modules under various partial shading situations,” Solar Energy, vol. 193, pp. 814–819, Nov. 2019