From shine to decline: Degradation of over 1 million solar photovoltaic systems in Germany

Solar photovoltaic systems are central to the future of electricity production worldwide. However, their performance degrades with age. The rate of decline in real-world usage critically affects the financial viability and carbon mitigation potential of photovoltaic installations. Earlier studies are typically limited by small sample sizes or short observation periods, and limited treatment of a potential non-linear relationship to environmental factors. This study uses high-dimensional fixed-ef