Advances and Challenges in Solar Energy Conversion: Technologies, Integration Pathways, and Future Prospect

Abstract

Solar energy stands as the cornerstone of the global transition towards sustainable energy systems. Its abundance, scalability, and technological diversity make it the most promising renewable resource to address the twin challenges of climate change mitigation and energy security. This review paper provides a comprehensive analysis of recent advances in solar energy harvesting technologies, spanning photovoltaic (PV) devices, concentrated solar power (CSP), photothermal systems, solar-driven hydrogen production, and hybrid solar-energy storage integration. The paper examines material innovations, including perovskites, tandem solar cells, and nanostructured absorbers, alongside system-level strategies such as grid integration, demand-response coupling, and smart solar architectures. A comparative methodology is employed to evaluate efficiency improvements, cost reductions, lifecycle sustainability, and techno-economic viability across solar pathways. Results highlight that PV costs have fallen by over 85% since 2010, CSP systems achieve dispatchability through molten-salt storage, and emerging solar-to-hydrogen routes exhibit efficiencies above 15% at lab scale. Figures and tables present data trends, deployment scales, efficiency records, and integration challenges. Discussion emphasizes the barriers to large-scale solar deployment, including intermittency, land-use trade-offs, recycling of solar modules, and socio-economic considerations in different global regions. The review concludes that while no single solar pathway provides a universal solution, a diversified portfolio combining PV, CSP, storage, and solar fuels offers the most resilient route towards achieving net-zero energy systems. Future research must prioritize durability, circular economy principles, and policy frameworks that accelerate solar integration worldwide