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This paper presents the energy, exergy, and economic analysis of a new cogeneration cycle for the simultaneous production of power and cooling operating with an ammonia–water mixture. The proposed system consists of an absorption cooling system integrating a reheater, a separation tank, a compressor, a turbine, and an expansion valve. In addition, internal rectification is applied, improving the system's performance. Mass, energy, and exergy balances were applied to each system's component to evaluate its performance. Additionally, the costs of each component were determined based on economic equations, which take into account mass, heat flows, and temperature differences. A parametric analysis found that the system reached an energy utilization factor of 0.58 and an exergy efficiency of 0.26 using internal rectification at TG = 120 °C, TA = 30 °C, and TE = 10 °C. The power produced by the turbine was 26.28 kW, and the cooling load was 366.8 kW. The output costs were estimated at 0.071 $/kW. The condenser was found to be the most expensive component of the system, contributing 28% of the total cost. On the other hand, it was observed that the generator was the component with the highest exergy destruction, with 38.16 kW. [ABSTRACT FROM AUTHOR]

This study introduces and evaluates an innovative combined cooling, heating, and power (CCHP) system integrating a gas turbine cycle with transcritical and supercritical CO2 cycles, a high-pressure steam cycle, a Goswami cycle, and a heating terminal. The primary objective is to enhance the thermodynamic efficiency and reduce the environmental impact of power generation. Through detailed exergy and energy analyses, we assessed the system's performance and compared it with traditional energy systems. The methodology included evaluating the irreversibility within each component, particularly highlighting the gas turbine cycle's significant share of irreversibility at 67% and the chamber's highest exergy destruction. Our findings reveal that the integrated system achieves total energy, exergy, and electrical efficiencies of 68.83%, 34.63%, and 33.55%, respectively, while significantly reducing CO2 emissions to 0.298 kgCO2/kWh—outperforming coal, oil, and natural gas power plants in environmental sustainability. Furthermore, the integrated CCHP system showcases superior thermodynamic performance by achieving higher efficiency rates compared to existing solutions detailed in recent studies, thereby marking a significant step forward in the development of sustainable power generation technologies. This research underscores the potential of integrating transcritical and supercritical CO2 cycles with gas turbines to meet energy demands more efficiently and eco-consciously. [ABSTRACT FROM AUTHOR]

This research aims to explore the economic and energy efficiency ramifications of combining the supercritical carbon dioxide oxy-fuel cycle with the Goswami cycle in the context of integrated heating and cooling systems, as well as power generation. Oxy-fuel systems, known for their high operating temperatures. In oxy-fuel systems, gas turbine exhaust gases typically preheat incoming flows to the combustion chamber. Nevertheless, even after preheating the combustion chamber inlets, the exhaust gases from the gas turbine retain a relatively high temperature, demonstrating considerable potential for energy production. Through a comprehensive parametric study, the impact of independent parameters on system performance is systematically explored. Subsequently, a three-stage economic analysis, total capital investment cost estimation, total operating cost estimation, and income evaluation, is conducted. The investment return time is assessed based on the selling price of system products. In the final step, a genetic algorithm, combined with artificial intelligence, optimizes the system for rational and optimal economic and energy conditions. The research findings reveal that in the absence of the Goswami cycle, the system yields 13.5 MW of power and 8.5 MW of heating, with an investment return time of approximately 16.32 years. However, with the inclusion of the Goswami cycle, power production increases to 15 MW, accompanied by 5 MW of cooling and 6.7 MW of heating. Despite augmented initial and operational costs, the investment return time is significantly reduced to 9.9 years. The results of a three-objective optimization strategy, focusing on maximizing power, heating, and cooling, highlight the system's versatility. Opting for maximum power production enhances power by 12.53 % and cooling by 27.48 %, compared to the reference mode. However, heating production decreases by 37.01 %. Notably, total capital investment costs show improvement by about 4.54 %, and the pay-back time experiences a substantial reduction of approximately 27.68 %. Moreover, the levelized cost of energy decreases from 111.4 $/MWh in the reference state to 106.9 $/MWh, underscoring the economic efficiency of the integrated system.

A novel combination of a conventional combined power plant and low‐temperature power generators as a cogeneration cycle coupled with a biomass gasifier is presented in this study. For this purpose, mathematical modeling of organic Rankine cycle (ORC), Kalina, and Goswami cycles was performed as a bottoming power system. To achieve the goals of sustainable energy development, a portion of the fuel required for the proposed cycle has been provided using renewable biomass fuels. The results indicated that the base cycle heat recovery in all proposed scenarios would increase energy efficiencies by 6.1%, 3.3%, and 1.1%, respectively, to ORC, Kalina, and Goswami cycles. Furthermore, the results of the parametric studies on principal factors such as steam to biomass and equivalence ratios in the gasifier, working fluid types in the ORC, mass fraction of ammonia‐water mixture in Kalina and Goswami cycles, as well as thermodynamic properties of the expander and condenser can be highly considered for the energy industry developers. [ABSTRACT FROM AUTHOR]

A new cogeneration system is proposed consisting of biomass gasification fed by wood, a solid oxide fuel cell (SOFC) and a Goswami cycle, which is a combination of a Kalina and an absorption refrigeration cycle. The Goswami cycle acts as a bottoming cycle to recover waste heat of the SOFC in order to produce cooling effect along with additional electricity. The combined cooling and power (CCP) system is modeled via Engineering Equation Solver (EES) and assessed in terms of energy (or first law) efficiency and exergy (or second law) efficiency. The effects on the system performance of varying several key parameters are examined via sensitivity assessments. It is found that raising the SOFC current density increases the produced electricity generation and cooling, but reduces the energy and exergy efficiencies of the system. It is also found that, as the SOFC inlet flow temperature and the turbine inlet pressure increase, the electricity generation rate and the energy and exergy efficiencies of the system rise to the optimal values of 481.6 kW, 60.2% and 34.7%, respectively, and then decrease. The exergy analysis also demonstrates that the gasification reactor, the boiler and the second air heat exchanger are the main irreversible components. [ABSTRACT FROM AUTHOR]

The tar produced by biomass gasification can be challenging to handle in processing units. To address this issue, a new polygeneration structure based on tar combustion has been designed in this study. This structure has been developed using Aspen HYSYS software and consists of subsystems, including the tar combustion section integrated with a gas turbine cycle, a low-grade temperature section, a Goswami utility section, and a hydrogen production section. The products of this structure are 7920.65 kg/s of hot water, 33.52 kg/s of cold water, 0.56 kg/s of hydrogen, 4.444 kg/s of oxygen, and 222100 kW of power. The system is examined from various perspectives: energy, exergy, environment, and economics. The overall energy and exergy efficiencies are 89.72% and 54.53%, respectively. The exergy analysis exhibits a total irreversibility of 859,492 kW, in which the low-grade temperature section has the highest exergy destruction with a share of 72%. Accordingly, the environmental analysis demonstrates that the new process has zero indirect carbon dioxide emissions, and its footprint is equivalent to 0.22 kg CO2 /kWh. Also, the products have been produced according to economic estimates with a cost of energy of 0.0068 $/kWh and a total unit cost of products of 0.0274 $/GJ. [Display omitted] [ABSTRACT FROM AUTHOR]

This paper presents a theoretical investigation of a combined Power and Cooling Cycle that employs an Ammonia-Water mixture. The cycle combines a Rankine and an absorption refrigeration cycle. The Goswami cycle can be used in a wide range of applications including recovering waste heat as a bottoming cycle or generating power from non-conventional sources like solar radiation or geothermal energy. A thermodynamic study of power and cooling co-generation is presented for heat source temperatures between 100 to 350 °C. A comprehensive analysis of the effect of several operation and configuration parameters, including the number of turbine stages and different superheating configurations, on the power output and the thermal and exergy efficiencies was conducted. Results showed the Goswami cycle can operate at an effective exergy efficiency of 60-80% with thermal efficiencies between 25 to 31%. The investigation also showed that multiple stage turbines had a better performance than single stage turbines when heat source temperatures remain above 200 °C in terms of power, thermal and exergy efficiencies. However, the effect of turbine stages is almost the same when heat source temperatures were below 175 °C. For multiple turbine stages, the use of partial superheating with Single or Double Reheat stream showed a better performance in terms of efficiency. It also showed an increase in exergy destruction when heat source temperature was increased. [ABSTRACT FROM AUTHOR]

The Goswami combined power/cooling cycle is an appropriate way to convert energy efficiently. However, in the conventional Goswami cycle (CGC), the refrigeration is not available when the absorber temperature is high. In the present study, a mechanically driven compressor is used to compress the vapors leaving the turbine. This design creates a line independent of the absorber temperature. An idealized cycle approach was used with the assumptions adopted by Goswami. As a result, under the same typical operating conditions, the thermal efficiency of the novel cycle is 27.52% with a net useful effect of 135.2 kW, while the thermal efficiency of CGC is 23.54% with a net useful effect of 99.47 kW. Moreover, at equal total heat input, the working fluid mass flowrate in the novel cycle is less than the CGC. Ultimately, the refrigeration limits highlighted in the CGC were overcome in the novel cycle which allows the availability of refrigeration regardless of the increase in absorber temperature. This advantage, combined with the improved thermal efficiency, suggests a short-to-medium-term payback time of the additional investment cost of the added components and a long-term profitability of the system. • The vapors recompression leaving the turbine improves the performance of the refrigeration and electricity production. • The novel cycle ensures availability of cooling capacity regardless of absorber temperature. • The working fluid load of the novel cycle is reduced at equal total heat input compared to the Goswami cycle. [ABSTRACT FROM AUTHOR]

Purpose – The proposed solar thermal cooling cogeneration cycle is well suited for industrial as well as domestic needs and it eliminates need of electricity for refrigeration system. The purpose of this paper is to integrate power and cooling to minimize the energy usage. Design/methodology/approach – The proposed plant has double turbine with superheater and reheater to extract more energy, operating on single generator. The saturated refrigerant from the exit of the generator is used to run the primary turbine and the exit mass of refrigerant is split into 50:50 cooling to power ratio. Findings – It produces additional power of 24 kW at absorber concentration of 0.42 and turbine inlet concentration of 0.95, with separator temperature of 145°C and atmosphere temperature of 30°C. Research limitations/implications – The proposed cooling cogeneration cycle is possible to run on all the refrigerant working fluid mixture and it overcomes the problem of Goswami cycle which is not possible to run in hot climatic countries. Originality/value – The cycle can operate individually as refrigeration cycle, power cycle and both and it will run all climatic conditions. [ABSTRACT FROM AUTHOR]

• A novel freshwater, cooling, and power trigeneration system based on solar energy and molten salt storage is designed. • The proposed system aims to satisfy the water and power shortage in a southern city of Iran. • The performance of the system is evaluated under worst weather conditions in summer time. • The system is optimized in four different scenarios to identify optimum operating conditions. In summer, the coastal areas of southern Iran suffer from the freshwater shortage and electricity instability. Meanwhile, this region benefits from the high intensity of solar radiation and the huge potential of brackish water resources. Hence, this paper designs a novel cooling, power and pure water trigeneration system for application in this area to mitigate its energy and water crisis. The proposed system is composed of a solar-based Goswami power and cooling production cycle and a multistage flash seawater desalination process. Moreover, a molten salt heating energy storage unit is used to prove its steady operation under uncertain sunlight condition. A comprehensive parametric study is provided to evaluate the system performance by changing the key variables. The numerical results demonstrate that increasing the pressure ratio from 6 to18 causes 3.3% leads to an increase in system efficiencies and minimum total products cost experiences at the pressure ratio of 12.6. Additionally, as the superheating degree increases from 0 to 10 K, the energy efficiency decreases but the exergy efficiency increases. When the ammonia concentration at the rectifier exit is increased from 0.965 to 0.995, the energy efficiency increases 5%, the exergy efficiency has a decreasing trend from 28% to 25.9%, and the minimum total products cost is 131.2 $/GJ. Furthermore, the exergy efficiency gains its maximum, the energy efficiency has a minimum value, and the total products cost grows with higher values of the minimum approach temperature. Finally, the system is optimized under four different scenarios to identify its best operating condition in each condition: three single-objective and one multi-objective optimization cases. The results of the multi-objective optimization are trade-offs between the ones for single-objective optimization cases. In this case, the net power of 12 MW, cooling capacity of 15.74 kW, and the freshwater of 4.72 kg/s are attainable. [ABSTRACT FROM AUTHOR]

One of the necessities of human beings in this century is the potable water supply. This supply has more environmental benefits if the potable water is supplied by renewable energy resources. In this paper, a combination of combined cooling and power system (Goswami cycle), with the reverse osmosis and sodium hypochlorite plant powered by geothermal energy resources is proposed. The products of this system are electrical and cooling energy, potable water, hydrogen and salt. To investigate all of the system aspects, energy, exergy, economic, exergoenvironmental, and environmental analyses are performed. In environmental analysis, the social costs of air pollution are considered. It means that for the same amount of system electrical power produced by non-renewable energy resource power generation systems, the produced air pollution gases and their costs considering the social cost of air pollution are quantified. In this regard, four scenarios are defined. Results show this multi-generation system produces 1.751 GJ/year electrical energy, 1.04 GJ/year cooling energy, 18,106.8 m3/year potable water, 7.396 Ton/year hydrogen, and 3.838 Ton/year salt throughout a year. The system energy and exergy efficiencies are equal to 12.25%, and 19.6%. The payback period time of this system is equal to 2.7 years. • A novel desalination multigeneration system powered by geothermal energy is proposed. • 5E analyses of multigeneration system producing electricity, cooling, potable water, hydrogen and NaClO • The cogeneration system combines geothermal energy with reverse osmosis and electrolysis process. • The system energy and exergy efficiencies are equal to 12.25% and 19.6%. • The payback period time of this system is equal to 2.7 years. [ABSTRACT FROM AUTHOR]

• A modified Goswami cycle configuration for a geothermal application is proposed. • Thermodynamic and component costs modeling is established in detail. • Comparison of Goswami cycle with an Organic Rankine cycle/absorption chiller system. • Energy, exergy, and component costs analysis considering the Torre Alfina reservoir. • Goswami system shows higher exergy efficiency and lower cost at same power produced. Combined cooling and power production can improve the overall efficiency of a geothermal energy conversion system. Most systems have complex structures, characterized by a large number of devices resulting in a greater heat loss, low energy conversion efficiency and higher costs. This paper presents a geothermal system based on a modified Goswami cycle, aimed to produce cooling and power simultaneously in one loop. The proposed system has a simple structure with few components, and the heat rejected to the environment by the rectifier is internally recovered to preheat the strong solution, involving lower heat losses and higher conversion efficiencies. In order to investigate the exergy destructions and losses, the overall performances, and the total absolute component cost, the modeling of the proposed system is established in detail. The Goswami system performance is evaluated for the conditions of an actual application, the geothermal reservoir of Torre Alfina (Italy), and the results compared with those of a cascade system based on organic Rankine cycle coupled with a water/lithium bromide absorption chiller. Results show that for the same power output produced in both systems, the best scenario is the Goswami cycle system with an exergy efficiency of 35.53% against 32.77% of the cascade system case. In addition, the component cost analysis showed that the highest total absolute component cost is obtained for the cascade system case with a total of 14.6 M€, while the Goswami case showed a lower value with a total of 11.8 M€. [ABSTRACT FROM AUTHOR]

• Different technologies for low-grade heat recovery were assessed. • Kalina, Goswami, organic Rankine and trilateral flash cycles were investigated. • The foremost optimized bottoming cycle for low-grade heat recovery was introduced. • Sensitivity of the payback to economic factors were studied and evaluated. • The minimum sold price for generated electricity of each cycles were determined. The issues like depletion of fossil fuels and environmental concerns encourage policy makers to run different types of power plants, including gas-turbine power plants more efficiently. For this purpose, bottoming cycles can be employed to recover the low-grade thermal energy of the exhaust gases of the gas cycle. Kalina, organic Rankine, Goswami, and trilateral flash cycles were examined to be used as the second bottoming cycle of a gas-turbine power plant to scavenge low-grade thermal energy in the exhaust of an absorption refrigeration cycle as the first bottoming cycle. All alternatives to the secondary bottoming cycle were modeled and optimized by non-dominated sorting genetic algorithm II in MATLAB software considering energy and economic criteria. Then, the best alternative among optimized cycles was introduced. It was found that the best alternative is Goswami cycle, and the less desired one was Kalina cycle. Goswami cycle enabled to generate 4.26 MW of additional power as well as an additional 0.45 MW of an auxiliary cooling that reduces the required capacity of the chiller by 3.2%. The introduced foremost bottoming cycle increased the thermal efficiency of the power plant from 38.1 to 46.5%. The investments required for installation and usage of the best and worst bottoming cycle were determined to be paid back within 3.8 and 20.5 years, respectively. To have economic justification, the sold price of the best bottoming cycle (Goswami cycle) must be greater than 0.09 $.(kWh)−1 on average. [ABSTRACT FROM AUTHOR]

Thermodynamic cycles to produce power and cooling simultaneously have been proposed for many years. The Goswami cycle is probably the most known cycle for this purpose; however, its use is still very limited. In the present study, two novel thermodynamic cycles based on the Goswami cycle are presented. The proposed cycles use an additional component to condense a fraction of the working fluid produced in the generator. Three cycles are modeled based on the first and second laws of thermodynamics: Two new cycles and the original Goswami cycle. The results showed that in comparison with the original Goswami cycle, the two proposed models are capable of increasing the cooling effect, but the cycle with flow extraction after the rectifier presented higher irreversibilities decreasing its exergy efficiency. However, the proposed cycle with flow extraction into the turbine was the most efficient, achieving the highest values of the energy utilization factor and the exergy efficiency. It was found that for an intermediate split ratio value of 0.5, the power produced in the turbine with the flow extraction decreased 23% but the cooling power was 6 times higher than that obtained with the Goswami Cycle. [ABSTRACT FROM AUTHOR]