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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]

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]

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]