This paper describes an innovative renewable-energy approach aimed at minimizing fossil fuel reliance for power generation and heat supply. This strategy encompasses renewable energy storage, power production, and heat supply. By harnessing solar and other renewable energies, hot water is produced and preserved underground with minimal heat loss over time, termed Utility-Scale Underground Hot-Water Storage (USUHWS). Comparative analysis reveals that for equivalent work storage, USUHWS demands over 140 times less capital than battery-based grid storage and boasts an efficiency of more than 80 times greater than Pumped-Storage Hydropower (PSH) regarding storage density. As such, USUHWS has the potential to supersede fossil fuels in national energy storage systems. On-demand, this stored hot water can be used to produce electricity on a utilityscale, novel air-water thermal power plant, operating at temperatures close to 100°C. Thermodynamic assessments indicate that this power plant could achieve a 300-megawatt capacity, mirroring fossil fuel-driven plants but with negligible greenhouse gas emissions. Consequently, these air-water power plants might replace fossil-fuel-dependent power plants in national grids, remaining resilient against weather variations. This presented solution offers a truly sustainable and cost-effective renewable energy alternative, devoid of hazardous materials and substantial environmental footprints. Unlike current renewable solutions focusing primarily on power generation, like wind turbines and PVs, this innovative approach also provides renewable heat, which accounts for nearly 30% of fossil fuel consumption, surpassing the present-day fossil fuel usage for power generation.