Johannes Weniger has been working in the PV industry since 2009 and is a founding member of the Solar Storage Systems Research Group at the University of Applied Sciences HTW Berlin. He initiated the Energy Storage Inspection in 2018 and has reviewed over 100 residential PV-battery solutions. Johannes Weniger earned his doctoral degree in the Department of Electrical Energy Storage Technology at the Technical University of Berlin. In 2026, he founded aquu, a research institute specializing in evaluating the performance and quality of battery systems and pv installations.