Enhanced Power Generation Through Hybrid Solar Chimney Coupled With a Steam Turbine Power Plant Leveraging Heat Recovery

The incorporation of solar chimneys and fossil fuel power plants plays a beneficial role in reducing fuel consumption and environmental pollution. The need to pay attention to the turbine placement and the advantage of waste heat recovery from energy resources also increased the importance of the issue. In this study, the potential of integrating waste heat resources of a steam power plant is explored to increase the overall efficiency of a solar chimney power plant (SCPP). The effects of utilizing expelled heat from wet cooling towers and stack's flue gas are taken as waste resources and are numerically studied on preheating the inlet air of the collector of the SCPP. The influences of designing the proper geometry of the flue gas chimney inside the collector are studied on the air entering the main chimney of the SCPP and the height of the flue gas chimney on the output power. The impact of allocating the semitransparent walls for flue gas chimney is analyzed on the gas temperature and the overall efficiency of the SCPP. Three-dimensional numerical simulations are adopted to contribute to a direct reduction in water consumption in wet condensers and an indirect reduction in fuel consumption of the steam turbine power plant. Based on numerical results, the proper vertical position of the turbine showed the pronounced effect on the output power of the SCPP. The choice of adding simultaneously radiators and flue gas chimney on the output power of the SCPP has become more important than that achieved by the addition of only radiators in all flue gas chimney heights. Ultimately, identifying the best turbine position and the most effective flue gas chimney height led to a 214.1% increase in the overall efficiency of the hybrid SCPP compared to the conventional Manzanares SCPP.