Solar energy, as a clean and renewable resource, plays a pivotal role in addressing global energy demands and mitigating climate change. This study explores the advancements in solar thermal energy systems, focusing on the design, performance, and optimization of solar collectors, thermoelectric generators (TEGs), hybrid photovoltaic-thermal (PVT) systems, and thermal energy storage (TES) technologies. Experimental investigations were conducted on flat plate collectors, evacuated tube collectors, and parabolic trough systems, evaluating the impact of working fluids, surface modifications, and solar irradiance on efficiency. Nanofluids, such as CuO and Al₂O₃, were tested for enhanced heat absorption, while absorber surface modifications like black chrome and textured surfaces were analyzed for improved thermal performance. Additionally, the study examined the integration of TEGs with solar collectors and the performance of hybrid PVT systems under varying environmental conditions. Thermal energy storage methods, including sensible heat storage, latent heat storage using phase change materials (PCMs), and thermochemical storage, were also investigated to enhance system reliability and efficiency. The findings highlight the importance of optimizing system design, material selection, and operational parameters to maximize solar energy conversion and storage. This research provides valuable insights into advancing solar thermal technologies for sustainable energy solutions.