A novel solar assisted vacuum thermionic generator-absorption refrigerator cogeneration system producing electricity and cooling.

• An APR is proposed to act as bottoming cycle for a solar assisted VTIG system. • Performance parameters evaluating the proposed system are specified. • Integration an APR is effective to improve the system performance. • Influences of key parameters on the proposed system performance are revealed. A novel solar assisted cogeneration system composed of a parabolic dish collector (PDC), a vacuum thermionic generator (VTIG), and an absorption refrigerator (APR) is proposed, in which the APR harvests the rejected heat from the VTIG for further cooling production. The equivalent power output and efficiency of the proposed system are obtained by considering various irreversible losses including radiation and convection heat losses of the PDC, radiation heat losses between the cathode and anode of the VTIG, heat transfer irreversibility, irreversible effects inside the working fluid of the APR. The maximum attainable efficiency increases from 17.21% to 27.06% as the bottoming APR is hybridized into the system. Meanwhile, the corresponding power density gains a 13.47% increase. Comprehensive sensitivity analyses are conducted to examine the dependence of the proposed system performance on some decisive design parameters and operating conditions such as absorber temperature of the solar collector, solar concentration ratio, solar irradiance, work function and anodic temperature of the VTIG, heat transfer area, heat transfer coefficient, and internal irreversibility factor of APR. The obtained results may provide some new insights into development and operation of such a solar powered cogeneration system. [ABSTRACT FROM AUTHOR]