Investigation of a Novel Solar Powered Trigeneration System for Simultaneous Production of Electricity, Heating, and Refrigeration Below Freezing

Abstract

A solar powered trigeneration system consisting of tower solar collector, Kalina cycle with the heat exchanger, and ejector-absorption refrigeration cycle is proposed to produce refrigeration below freezing, electricity, and process heat, simultaneously. Simulation through computational fluid dynamics using ansys-fluent package is conducted to examine the effect of coil diameter and inlet oil temperature on the pressure and temperature of solar heat transfer fluid. It is found that, for inlet temperature of 92 °C and direct normal irradiations of 850 W/m2, the solar heat transfer fluid outlet temperature increases by 9% when the coil diameter increased from 150 to 400 mm. Trigeneration performance is analyzed after altering hot oil outlet temperature, turbine inlet pressure, and the concentration of ammonia–water basic solution to study their effect on power produced by turbine, refrigeration load, exergy of refrigeration, and efficiencies of trigeneration system. An increase in the concentration of the ammonia–water basic solution is leading toward the significant increase in the turbine power and the elevation of trigeneration system’s energy and exergy efficiencies. Bottoming of the Kalina cycle with ejector-absorption refrigeration cycle shows the distribution of solar energy as energetic output 72.31% and energy lost to environment 27.69%. The solar exergy supplied to the trigeneration system is distributed as follows: 16.23% is the exergy produced, 1.62% is the exergy loss, and 82.15% is the exergy destroyed.