Solar Energy Conversion at Scale: Performance Progress, Integration Strategies, and the Next Technology Frontiers

Abstract

Solar energy is increasingly central to decarbonization because it can be deployed at multiple scales—from rooftops to utility-scale plants—and coupled to storage and sector-coupling pathways. This review synthesizes progress across photovoltaics (PV), concentrated solar power (CSP), photothermal conversion, and solar-driven fuel production, with an emphasis on integration options that improve reliability and system value. We compare technology pathways using conversion performance, levelized cost of electricity (LCOE), storage compatibility, and life-cycle indicators, complemented by case-study evidence from diverse climates and grid contexts. Reported trends show large cost declines for PV since 2010, dispatchability advantages for CSP when paired with molten-salt thermal storage, and fast-rising laboratory efficiencies for emerging absorbers such as perovskites and tandem architectures. We also discuss intermittency management through batteries, thermal storage, and hydrogen as a long-duration option, alongside sustainability challenges including land-use trade-offs, water constraints for steam-cycle CSP, and end-of-life recycling and critical-material recovery for PV modules. The analysis highlights that the next phase of solar deployment depends less on proving technical feasibility and more on scaling integrated, circular, and equitable energy-system designs.