techno-economic Modeling an‎d optimization of an innovative integrated system for power, cooling, heating an‎d water production

10/12/2026 12:00:00 AM

In this study, an innovative tetra-generation Integrated system of power, heating, cooling an‎d fresh water (CCHPW), which has not been proposed an‎d investigated so far, is modeled an‎d optimized for a residential complex. This system uses a gas engine an‎d an organic Rankine cycle (ORC) for electricity generation, an‎d an adsorption chiller (with three adsorbent beds an‎d two evaporators) for cooling, along with a vapor compression refrigeration cycle (VCR) with a cold thermal energy storage (CTES) with spherical capsules filled with water. A reverse osmosis (RO) desalination unit was used for freshwater generation, an‎d the exhaust an‎d cooling water of the gas engine were used for heating. Part of the exhaust heat from the gas engine is used in the ORC an‎d the other part, along with the heat from the engine cooling water, is used for the adsorption chiller desorption bed an‎d hot water production. The water entering the RO desalination unit is first preheated by the ORC condenser, which reduces the energy consumption of the high-pressure pump. In addition, a Pelton turbine also recovers the energy of the concentrated brine exiting the RO. Then, in the next step, the optimization of the proposed system was carried out in a two-objective manner (with the objective functions of exergy efficiency an‎d annual relative benefit) an‎d the optimal values of 9 design variables were reported. Annual relative benefit is a new an‎d appropriate objective function that shows whether the designed system is cost-effective compared to the conventional system (i.e., purchasing electricity from the grid, hot water boiler for heating, VCR only for cooling, an‎d purchasing water from the grid). The results showed that in the optimal case, first, using the proposed four-stage CCHPW system is cost-effective an‎d acceptable compared to the conventional system, with a payback period of 3.86 years. Secondly, the equipment selec‎ted in the optimal mode is: two gas engines with a power of 509 kW, an ORC system with a power of 145/84 kW an‎d a thermal efficiency of 28/34%, an adsorption chiller with a cooling capacity of 82/94 kW. Also, the volume of CTES was 42.23 m^3 . The daily production of fresh water by the RO system is 245.44 m^3. The integrated system, in the optimal mode, showed an exergy efficiency of 36.94%, an‎d an energy efficiency of 60.29%, an‎d an annual relative benefit of 2.3596×〖10〗^5 $⁄year. Importantly, although the cost of installing an‎d maintaining equipment in the integrated system is 8.183 times that of the conventional system, the operating cost an‎d environmental impact penalty in it are 59.64% of the conventional system. Also, the emission of 〖CO〗_2 an‎d 〖NO〗_x in the conventional system is 2.33 times that of the proposed system. In addition, the VCR-CTES system with an adsorption chiller reduces electricity consumption by 25.34% an‎d its cost by 26.78% annually compared to the conventional VCR.

سيستم يكپارچه , چيلر جذب سطحي , مخزن ذخيره سرمايش , نمك‌زدايي اسمز معكوس , بهينه‌سازي

Integrated system , adsorption chiller , cold thermal energy storage , reverse osmosis desalination , optimization

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