# Progress in Improving Photovoltaics Longevity
## 5 Discussion
Therefore, the retirement of PV after reaching the limit of 80% is not an option when the photovoltaic operation is economically viable and profitable. In this context, warranties for an operational lifetime of 40 years and up to 70% of initial performance have been started to be offered by PV companies. Moreover, improving the performance during operation can enhance the lifetime duration of the warranty. Since the degradation rate is the most influential factor in the PV threshold performance and replacement, reducing it by appropriate methods will improve their lifetime with an even higher period of operation and affordable electricity generation. This is especially important for a building's integration of photovoltaics, where a replacement may not be easy and given that building components are constructed for longer operation periods. For example, building skin PV integration with limited or low rates of back-side PV ventilation results in higher module temperatures and higher thermo-mechanical stresses [88]. Therefore, degradation rates can be enhanced with a reduction of the BIPV component lifetime, a result that can be amplified due to urban overheating and climate change, while drastically affecting BIPV operation, especially in hot climatic conditions. In addition, improving PV modules' lifetimes will extend the period needed for developing the appropriate PV recycling infrastructure in their large-scale implementation with a sustainable reduction in the necessary resources needed for recycling [222]. As it is fully evident from the data assessment of the parameters affecting the degradation rate analyzed in this study, heat accumulation and temperature overheating of PV modules are detrimental factors in their operational phase. Therefore, research in developing efficient and easy-to-install PV coolers or reducing required resources and simplifying the operation of photovoltaic thermal (PVT) solar systems should be among the research priorities in the tens of TW of PV installation required for the energy transition [223]. To achieve a sustainable cycle of PV systems, future research should head toward the implementation of recycling strategies [12] for PV module waste. One promising approach is the establishment of specialized recycling facilities, where targeted recovery of valuable materials, including glass, silver, aluminum, and silicon, will be carried out. The disman  
Figure 8: The PV reliability learning cycle for continuous improvement aims to maintain quality despite continuous changes [153]. This cycle aligns with key standards in photovoltaic (PV) module manufacturing and quality management, including EN IEC 62941:2020 for PV module quality systems [217], ISO 9001:2015 for quality management systems [218], IEC 61215-1:2016 for PV design qualification and type approval [219], IEC 61730-1:2016 for PV safety qualification requirements [220], and IEC 61215:2016 for crystalline silicon PV module qualification [221]. ting of PV panels includes appropriate material separation through chemical, mechanical, and thermal processes. It ensures that worthwhile resources are being reused, significantly limiting the environmental impact of the solar industry. Moreover, the integration of closed-loop recycling systems provides the reassurance that the recovered materials are then reintroduced into the production process, reducing the dependence on raw resources and materials. The adoption of eco-design principles, which enable the incorporation of easy-to-recycle materials in PV module manufacturing technology, is also suggested, as it will embrace end-of-life recycling. Supplementary, enhanced techniques, including the recovery of specialty metals from thin-film modules, continue to evolve, enhancing the efficiency and economic feasibility of the recycling processes [224]. The superposition of all these concerted efforts reveals a broader purpose of creating a circular economy for PV systems, promoting resource conservation, and minimizing waste.