In this paper, using a thermodynamic rules, a multigeneration energy system with an initial stimulus of microturbine has been modeled. Then, using the concept of exergy and applying economic and environmental functions, exergy efficiency and total cost rate are calculated as two objective functions. Due to the contradiction of the objective functions, a multiobjective firefly algorithm is used to optimize the system. To accelerate the process of optimization and to prevent algorithm capture in local optimizations, new algorithms have been added to the innovative algorithm. The result of applying the algorithm on the multigeneration energy system will result in a set of Pareto-optimal solutions, indicating the compromise between the target functions. A fuzzy decision making based on max-min approach is used to select the desired solution between the Pareto-optimal solutions. In order to evaluate the efficiency of the proposed optimization algorithm, the results of this algorithm are compared with two particle swarm optimization algorithms and multi-objective genetic algorithm. Based on the results of system optimization, the exergy efficiency can increase up to 69%. Also, considering the total cost rate of the system as the only target function, this can be reduced to 572$/h.

Biomass gasification is the process of converting biomass into a combustible gas suitable for use in boilers, engines, and turbines to produce combined cooling, heat, and power. This paper presents a detailed model of a biomass gasification system and designs a multigeneration energy system that uses the biomass gasification process for generating combined cooling, heat, and electricity. Energy and exergy analyses are first applied to evaluate the performance of the designed system. Next, the minimizing total cost rate and the maximizing exergy efficiency of the system are considered as two objective functions and a multiobjective optimization approach based on the differential evolution algorithm and the local unimodal sampling technique is developed to calculate the optimal values of the multigeneration system parameters. A parametric study is then carried out and the Pareto front curve is used to determine the trend of objective functions and assess the performance of the system. Furthermore, sensitivity analysis is employed to evaluate the effects of the design parameters on the objective functions. Simulation results are compared with two other multiobjective optimization algorithms and the effectiveness of the proposed method is verified by using various key performance indicators.

The system underwent a thermodynamic analysis in this research, focusing on the generation of energy, cooling, heating, hydrogen, and freshwater across multiple generations. The primary energy source for this cycle is a solar parabolic trough collector (PTC). In this solar collector, Al2O3 Therminol VP1 nanofluid is used as the working fluid. The multigeneration system includes the following subsystems: A steam Rankine cycle and an organic Rankine cycle for power production, a double-effect absorption refrigeration system for cooling, a domestic water heater for hot water generation, a proton exchange membrane (PEM) electrolyzer for hydrogen production, and a reverse osmosis (RO) desalination unit for freshwater production. The ORC cycle will incorporate a thermoelectric generator (TEG) unit instead of a condenser to produce additional power. The system's efficiency is analyzed concerning various factors and nanoparticle concentrations. The findings indicate that the energetic efficiency of the system is 33.81%, while the exergetic efficiency is 23.59%. Additionally, the production rates of hydrogen and freshwater increase with higher nanoparticle volume concentrations and solar irradiation. It was also observed that the coefficient of performance (COP) of the cooling system improves with increasing desorber temperature.

Using renewable energy is an efficient method for addressing the drawbacks of utilizing fossil fuels. The study focuses on a multigeneration system that integrates PTC solar collector and geothermal energy, along with two ORC cycles, a single-effect absorption refrigeration cycle, a PEM electrolyzer, and a dryer. A TEG unit is utilized in the ORC cycles to increase power production. The system is analyzed from energy, exergy, and exergoeconomic perspectives using EES software. Parametric analysis is conducted to assess the impact of crucial parameters on the system's performance. The examination of overall results reveals that the energetic and exergetic efficiencies of the multigeneration system are 41.58 and 25.61%, respectively. The power generated by ORC1 turbine and ORC2 turbine are 461.9kW and 227.6kW, respectively. Introducing TEG units in place of condensers in the ORC cycles results in increased power production to 138.2kW and 328.2kW for ORC1 and ORC2 cycles. The energetic and exergetic COPs of the system are 0.8103 and 0.3484, respectively. Additionally, the multigeneration system is capable of producing 493.1 kg/day of hydrogen. Lastly, six different working fluids in the ORC cycle were investigated. It is demonstrated that among the 6 working fluids, n-pentane exhibited the best performance.

Recently, discussions about energy and global warming have significantly increased the focus on renewable energy. One of the suitable options for this purpose is the use of multigeneration systems with solar and geothermal energy sources. In this research, a multigeneration system for hydrogen, cooling, heating and power production based on the organic Rankine cycle, absorption chiller cycle dryer, and the proton exchange membrane (PEM) electrolyzer is investigated from thermodynamic and thermoeconomic points of view. In the organic Rankine cycles (ORC), a thermoelectric generator (TEG) unit is applied instead of a condenser, and different working fluids are tested to study their performance on the system. All the simulations are carried out using the Engineering Equation Solver (EES) software. The impact of different factors on the efficiency of the multigeneration system is investigated. The system's energetic efficiency is measured at 41.58%, while its exergetic efficiency stands at 25.61%, according to the findings. Moreover, by using the TEG unit, 466.4 kW extra power is obtained. Furthermore, the system can generate 493.1 kg/day hydrogen. From an exergy destruction perspective, the solar collector and the PEM electrolyzer exhibit the highest amounts. Finally, it is demonstrated that the geothermal temperature and turbine inlet temperature positively impact the system’s performance, while collector inlet temperature leads to a decrease in performance.

In the near future, hydrogen is expected to become a significant fuel that will largely contribute to the quality of atmospheric air. Hydrogen global production has so far been dominated by fossil fuels. Pure hydrogen is also produced by electrolysis of water, an energy demanding process. In this study a novel multigeneration system is introduced using nanofluid in the solar system. The proposed system includes a quadruple effect absorption refrigeration cycle, a thermoelectric generator, a PEM electrolyzer, vapor generator and domestic water heater. A parametric study is accomplished to consider the effect of significant parameters on the efficiency of the system. It is observed that the power generated by the system is 18.78 kW and the collector energy and exergy efficiency are 82.21% and 80.48%, respectively. Furthermore, the results showed that the highest exergy destruction rate occurs in the solar system at the rate of 4461 kW. The energy and exergy COPs of the absorption chiller are discovered to be 1.527 and 0.936, respectively. The amount of hydrogen production rate decreases by increasing the volume concentration of the nanoparticles, the solar radiation and the figure of merit index.

In this study, a novel multigeneration cycle including PTC and geothermal as the main energy sources and Kalina and ORC cycles as the main power production cycles have been proposed and analyzed from energy and exergy point of view. The effect of important parameters including solar irradiation, collector inlet temperature, collector volumetric flow, environment temperature, and geothermal temperature on the amount of the hydrogen production rate, freshwater production rate, and system efficiency have been investigated. The results show that the energy and exergy efficiency of the proposed system is 35.75 % and 18.39 %, respectively. Moreover, the total power produced by the system is obtained to be 1545 kW, the amount of hydrogen produced is 0.001175 g/s and the freshwater production rate is 5.216 kg/s. Furthermore, the results indicated that increasing geothermal temperature and solar collector inlet volumetric flow, increase hydrogen production rate and solar irradiation and environment temperature have no effects on the hydrogen production rate of the cycle. Finally, it is found that geothermal temperature increase and collector volumetric flow show an optimum point for thermal efficiency and freshwater, respectively.

In this study, renewable energy sources including a high-temperature solar parabolic trough collector and geothermal water integrated with a modified Kalina cycle, a combined ORC-EJR cycle, an electrolyzer, an RO desalination unit, and a domestic water heater. SiO2 and TiO2 nanoparticles dissolved in Therminol VP1 are applied as the working fluid of the solar collector. A comparative analysis of introduced working fluids is performed from energy, exergy as well as cost analysis point of view to evaluate their efficiencies. Solar irradiation, ambient temperature, and collector inlet temperature were the parameters investigated to discover their effects on energy and exergy efficiency, solar collector outlet temperature, hydrogen production rate, and freshwater production rate. The highest generated outlet temperature of the solar collector outlet was 693.8 K obtained by Therminol VP1/SiO2 nanofluid. The maximum energy and exergy efficiencies of the proposed system were 36.69 % and 17.76 %, respectively. Moreover, it is found that by increasing the solar collector inlet temperature, the hydrogen production rate decreases while the water production rate increases.

In this research, thermodynamic and thermoeconomic analysis of a new multigeneration system based on the Parabolic trough collector and the photovoltaic-thermal solar collectors is carried out to produce power, cooling, hot water, hydrogen and freshwater. The proposed system includes an organic Rankine cycle, double-effect absorption refrigeration system, PEM electrolyzer and the reverse osmosis desalination unit. Analysis of energy, exergy, thermoeconomics, as well as analysis of various parameters was done by using the EES software. The results show that the energy and second law efficiency of the system is 33.49% and 13.31%, respectively. The net power produced by the system is 1271.48 kW in which ORC turbine has the maximum share. Moreover, the coefficient of performance of the cooling system is achieved to be 1.097 by considering the basic assumptions. The hydrogen and freshwater production rates are 542.3 kg/day and 4.55 kg/s, respectively. Finally, the rate of exergy destruction in each part of the system shows that the highest rate of exergy loss occurs in the PTC collector and the organic Rankine cycle with the amount of 53575 kW and 1624 kW, respectively, and in the organic Rankine cycle, the thermoelectric generator unit and evaporator have the largest share of exergy losses.