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.

Summary The present study reports the experimental results of a new absorption cooling system utilizing stainless steel plate heat exchangers in all the main components. The system operated with the ammonia‐lithium nitrate working pair. Several parametric analyses were performed in order to investigate the effect of the generation and condensation temperatures, solution mass flow rate, solution volume and expansion valve aperture on the cooling power, evaporation temperatures, and coefficient of performance (COP). Generation temperatures varied from 80°C to 95°C, while condensation temperatures varied between 20°C and 32°C. The system achieved a cooling power of 3.1 kW, cooling temperatures as low as 6°C, and internal coefficients of performance of approximately 0.62. The cooling power increased 20.3% with an increment of the solution mass flow rate from 1 kg/min to 4 kg/min. From the expansion valve analysis, it was found the cooling power varied from 0.28 to 2.29 kW while the COP varied from 0.032 to 0.23 for the corresponding test conditions.

Climate change is one of the main problems that humanity is currently facing due to carbon dioxide emissions caused by fossil fuel consumption. Organic Rankine cycles may play an important role in reducing these emissions since they can use industrial waste heat or renewable energies. This study presents the proposal and modeling of an organic Rankine cycle integrated into a double-effect absorption cooling system for the simultaneous production of power and cooling. The working fluids utilized were the ammonia–lithium nitrate mixture for the absorption system and benzene, cyclohexane, methanol, and toluene for the organic Rankine cycle. The influence of the primary operating parameters on the system performance was analyzed and discussed in terms of cooling load, turbine power, energy utilization factor, and exergy efficiency for a wide range of operating conditions. It was found that, for all cases, the cooling load was dominant over the turbine power since the minimum cooling load obtained was above 50 kW, while the maximum turbine power was under 12.8 kW. For all the operative conditions analyzed, the highest performance parameters were obtained for benzene, achieving an energy utilization factor of 0.854 and an exergy efficiency as high as 0.3982.

The present study reports the experimental results of a parabolic trough collector field and an absorption cooling system with a nominal capacity of 5 kW, which operates with the ammonia-lithium nitrate mixture. The parabolic trough collectors’ field consists of 15 collectors that are made of aluminum plate in the reflector surface and cooper in the absorber tube, with a total area of 38.4 m2. The absorption cooling system consists of 5 plate heat exchangers working as the main components. Parametric analyses were carried out to evaluate the performance of both systems under different operating conditions, in independent way. The results showed that the solar collectors’ field can provide up to 6.5 kW of useful heat to the absorption cooling system at temperatures up to 105 °C with thermal efficiencies up to 19.8% and exergy efficiencies up to 14.93, while the cooling system operated at generation temperatures from 85–95 °C and condensation temperatures between 20 and 28 °C, achieving external coefficients of performance up to 0.56, cooling temperatures as low as 6 °C, and exergy efficiencies up to 0.13. The highest value for the solar coefficient of performance reached 0.07.

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