Solar cells have emerged as one of the most promising renewable energy technologies for addressing global energy demands and reducing dependence on fossil fuels. The performance of solar cells largely depends on their ability to absorb sunlight efficiently and convert solar energy into electrical energy through photovoltaic processes. The present study investigates the light absorption characteristics and energy conversion mechanisms in solar cells using a comprehensive analytical and review-based approach. The study focuses on optical absorption, charge carrier generation, energy conversion efficiency, light-trapping mechanisms, semiconductor materials, and technological advancements in photovoltaic systems. The findings indicate that light absorption efficiency significantly influences solar cell performance by determining the number of charge carriers generated within the active semiconductor layer. Advanced photovoltaic materials such as silicon, thin-film semiconductors, perovskites, and quantum-dot-based systems demonstrate improved absorption characteristics and enhanced energy conversion efficiency. Modern light-trapping structures, nanophotonic engineering, and plasmonic enhancement techniques further improve solar energy harvesting by increasing optical confinement and reducing reflective losses. The study highlights the importance of optimising light absorption and charge transport processes for developing high-efficiency and sustainable solar energy technologies. Recent research demonstrates that advanced light-trapping architectures can substantially improve broadband absorption and photovoltaic performance.