The increasing demand for heating and cooling, coupled with growing environmental concerns, necessitates a paradigm shift towards sustainable thermal management practices. This paper presents a rigorous and scholarly investigation into innovative heating and cooling concepts, with a specific focus on the development and implementation of alternative refrigerants and waste heat recovery systems. The transition away from conventional refrigerants, with their detrimental impact on the environment, is explored through a comprehensive analysis of promising alternatives. Hydrofluoroolefins (HFOs), natural refrigerants (e.g., CO2, hydrocarbons, ammonia), and their blends are critically evaluated, considering their thermodynamic properties, environmental impact (GWP, ODP), safety considerations (flammability, toxicity), and application-specific performance. The paper delves into the intricacies of advanced cooling technologies, including absorption cooling, adsorption cooling, and thermoelectric cooling, examining their potential for enhanced energy efficiency and their ability to utilize low-grade heat sources. A significant contribution of this work lies in its in-depth exploration of waste heat recovery systems. Various techniques for capturing and effectively utilizing waste heat, such as heat exchangers, heat pumps, and organic Rankine cycles (ORCs), are comprehensively discussed and compared, with a focus on maximizing energy recovery and minimizing exergy destruction. The synergistic integration of these waste heat recovery systems with both conventional and alternative cooling technologies is examined, highlighting the potential for substantial energy savings and a reduced reliance on fossil fuels. The challenges associated with the adoption of these innovative technologies, including cost-effectiveness, material compatibility, system complexity, and safety implications, are critically assessed. Finally, the paper identifies key research gaps and outlines future directions in the pursuit of sustainable and efficient thermal management solutions, emphasizing the need for further research into novel refrigerants, advanced materials, optimized system design, and robust control strategies.