An integrated steam jet ejector power plant for drought adaptation considering water-exergy nexus in an optimal platform

Steam power plants contribute to anthropogenic climate change by emitting a considerable amount of carbon dioxide and losing significant freshwater. In the present study, a novel model-based steam jet ejector power plant is optimally designed to adapt to climate change by minimizing water losses and greenhouse emissions. An iterative thermo-mathematical program and a nonlinear mathematical model represent the system's energy and economic models. At the same time, an exergy analysis evaluates its performance according to the Second law of thermodynamics. A non-dominated sorting genetic algorithm generation III is interfaced with the developed empirical program to solve a multi-objective optimization model. Three decision-making scenarios including a maximum thermal efficiency (I), minimum cost of energy (II), and minimum heat losses (III) are considered to select appropriate configurations in the final Pareto front. Subsequently, a natural draft wet cooling tower and a once-through cooling system are coupled with the optimal configurations. The performance of the fully integrated systems is evaluated using four new water-exergy nexus criteria including water withdrawal for exergy dissipation, lost exergy for exergy dissipation, water consumption for fuel and product exergies. Finally, a sensitivity analysis is performed to take the environmental fluctuations and model uncertainties into account. The comparative results showed that water consumption for product and fuel exergies improved by 63.65 and 64.08%, while water withdrawal for exergy dissipation of the system was approximately nine times smaller than available model-based steam power plants. Moreover, the energy efficiency of the proposed system was 1.42% greater than the previous systems at the cost of 0.018 $/MJ more cost of energy. Thus, the proposed system can tackle drought and mitigate climate change with more investment in the energy sector.

Automated summary

A novel steam jet ejector power plant is designed to minimize water losses and greenhouse emissions to adapt to climate change. Nonlinear mathematical models and a Newton analysis are used to evaluate performance, while a non-dominated sorting genetic algorithm is used for multi-objective optimization. The proposed system shows improved water efficiency but higher energy costs compared to existing steam power plants.