Green roofs play a positive role in the fight against climate change by increasing biodiversity, improving the microclimate, and insulating the building. Many people are unaware that these benefits can be further enhanced when combined with a solar power system. This is because the plants cool and clean the photovoltaic (PV) modules, thereby increasing the system’s efficiency. 

Owners of historic buildings often have uncertainties regarding the potential installation of photovoltaic systems on their roofs. However, there are currently some changes in this area, and even the “German Foundation for Monument Protection” does not view monument preservation as conflicting with climate protection, as the installation of PV systems is often possible—provided the original building structure is protected and the installation is reversible. The presentation will delve deeper into precisely these two topics and provide answers to the most pressing questions.

In Part 8 of the independent and comprehensive online information session on Wednesday, April 22, 2026, from 6:00 to 7:30 p.m., a detailed overview will be provided on the topic of installing a PV system in combination with green roofs or historic preservation. 

The first part of the presentation covers the technical fundamentals of green roofs, the synergy effects of a solar green roof, recommendations for project implementation, and funding opportunities. The second part will address the legal framework for installing a PV system on historic buildings, followed by a presentation of the technical options, ranging from conventional rooftop systems to in-roof systems with colored solar modules or solar roof tiles. 

Finally, a guide for successful project implementation will be provided, and funding opportunities will be highlighted. The practical technical presentation will be supplemented by case studies and offers the opportunity to clarify questions directly with the experts, so that you can subsequently proceed with installing your own rooftop PV system in combination with a green roof or on your historic building.

The event is part of the online seminar series “Solar and Heat.” 

“In times of increasingly hot summers, the synergy effects of solar systems and green roofs highlight how important it is to consider climate protection and climate adaptation together. Preserving historic buildings through preservation is important, yet there are now several ways to install solar systems even in the vicinity of historic buildings,” says Janina Steinkrüger, Mainz’s Director of Environmental Affairs, looking forward to the eighth event in the “Solar” online seminar series.

The information series is organized by the climate protection managers, in collaboration with the adult education centers and the consumer advice center in the Rheinhessen-Nahe and Vorderpfalz regions. Further information on registration and the solar initiative of the state capital Mainz can be found at: www.mainz.de/solarinitiative