Prediction and assessment methods for sustainable solar energy systems within our planetary boundaries: how reliable are they?

This study presents a critical analysis of the sustainability of solar energy systems within the planetary boundaries framework, which sets the limits within which humanity can safely operate. Given the substantial contribution of the energy sector to global greenhouse gas emissions, solar energy has emerged as a crucial element in the shift toward a sustainable energy future. Nevertheless, numerous challenges impede solar energy systems reaching optimal effectiveness, encompassing technological and methodological sustainable tools constraints, environmental impacts, and socioeconomic implications. This research aims to comprehensively assess these challenges and propose strategies to surmount them through applying a Life Cycle Sustainability Assessment approach. The primary research question addressed is, "How reliable are the predictive and anticipatory assessment methods for sustainable solar energy systems within our planetary boundaries?" The study integrated circular economy principles, criticality evaluation, and advanced technological tools to enhance solar energy systems’ efficiency, environmental performance, and socioeconomic benefits. By addressing the entire life cycle of solar technologies — from material extraction to end-of-life (cradle-to-grave) — this work seeks to contribute to developing more sustainable solar energy systems that operate within the safe limits of our planet’s boundaries. The findings highlight the need for a holistic approach that not only focuses on technological advancements but also considers the broader environmental and socioeconomic impacts to ensure a truly sustainable energy transition. • Solar energy’s technological, environmental, social, and economic challenges. • Technical and methodological strategies for solar energy systems toward a sustainable model. • LCSA, circular economy, and criticality for advancing solar energy within safe planetary boundaries