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A hybrid energy system, comprising a diesel engine as the prime mover, electrical and absorption chillers, a backup boiler, and a multi‐effect distillation through thermal vapor compression (MED‐TVC) unit, has been utilized to meet the requirements of a residential complex. This study focuses on redesigning and optimizing the system to enhance environmental conditions, reduce pollutants, and minimize the use of fossil energy. The feasibility and design of renewable energy systems, including wind turbines (WTs), photovoltaic panels (PVs), and flat plate collectors (FPCs), have been examined. Genetic algorithm (GA) has been employed for optimization. The hybrid system employs 21 design variables, with 24 design variables chosen for optimization alongside renewable energies. The total annual cost (TAC), encompassing investment, operation, and pollution emission fines, has been chosen as the objective function for minimization. The results indicate that the use of WTs has not been cost‐effective, and solar energy can enhance the system's performance in Bandar Abbas, Hormozgan province in Iran. In the case of using a combined system, the objective function value was 2.0472 × 106 $/year, and when using renewable energies, the objective function became 1.6795 × 106 $/year. Thus, the proposed combined‐renewable system has reduced the objective function by 17.96%. [ABSTRACT FROM AUTHOR]

In present study, the thermal modeling and multi-objective optimization of shell and tube heat exchangers (STHE) with a diamond-shaped turbulator has been investigated. To obtain the Correlation relationship between the Nusselt number and the friction factor for a diamond-shaped turbulator, a CFD analysis with acceptable accuracy has been done. Two factors of total cost and maximum thermal effectiveness are chosen as two objective functions. Nine optimal design variables for the present study are arrangement, diameter, step ratio, length and number of tube, distance ratio and cut ratio of baffle, turbulator step ratio and turbulator internal rod diameter. The e-NTU procedure is employed for thermal modeling STHE and the Bell-Delaware technique is applied to evaluate the coefficient of heat transfer and pressure drop of the shell side. Also NSGA-II is used to acquire two objective functions. Comparison of the obtained results of the optimal Pareto optimal solutions showed that the use of diamond-shaped turbulator DST on the tube side improves thermal performance and lower overall costs STHE compared to the non-use state. Using turbulator inside the tube and the impact of important design parameters clearly contributed to the difference between effectiveness and overall cost. [ABSTRACT FROM AUTHOR]

In this study, a cogeneration system of heating, cooling and power used with the solar flat plate collectors (FPCs) and photovoltaic panels (PVs) integrates with a multi‐effect distillation through thermal vapor compression (MEE‐TVC), investigated as the first system to meet the loads of heating, cooling, electricity and fresh water. As an innovation, the combination of the first system with cooling and thermal storage tanks have been investigated. The systems are optimized with MATLAB and single‐objective genetic algorithm. The total annual cost considered as the objective function to compare the two systems and 36 and 61 design variables are obtained for the first and second systems, respectively. The design parameters considered for optimization included the capacity of the diesel engine as the prime mover, electrical chiller capacity, absorption chiller capacity, size of the boiler, partial loads of the diesel engine for each hour of the 2 days (1 day for hot months and 1 day for cold months), partial loads of the chillers for each hour of the first days (second day has no cooling load), number of FPCs and PVs, number of effects in the desalination unit, driving steam pressure, feed water flow rate, driving steam flow rate, and electric cooling ratio. The optimization aimed to fulfill the heating, cooling, electricity, and fresh water requirements of a residential town situated in Bandar Abbas, Hormozgan province, Iran. The second system's optimization results were compared with first system. The results have shown that the objective function for the first system was 2.6549×106$/year$$ 2.6549\times {10}^6\ \$/\mathrm{year} $$ and the initial investment cost was 9.1845×106$$$ 9.1845\times {10}^6\ \$ $$, and for the second system the objective function was 2.3549×106$/year$$ 2.3549\times {10}^6\ \$/\mathrm{year} $$ and the initial investment cost was 10.8790×106$$$ 10.8790\times {10}^6\ \$ $$. Therefore, by using energy storage, the objective function was reduced by 11.30%. [ABSTRACT FROM AUTHOR]