This book provides new techniques for recovering exhaust heat from gas turbines, natural gas combined cycle power plants, biomass boilers, and waste heat recovery from compost and wastewater treatment plants The book provides modeling for the study and comparison of combined cycle power plants with a heat recovery boiler of three pressure levels with reheating, inserting a technological improvement of solar hybridization and partial regeneration in the gas turbine. It assesses the environmental impacts and economic sustainability associated with these improvements. In addition, it proposes emissions minimization, with exhaust gas recirculation (EGR), and emissions treatment with a CO2 capture plant (CCP) and combined cycle power plant. Finally, it provides new insights into heat recovery from compost and exhaust gases recovery from wastewater treatment plants.