Thermo-economic analysis of solar-biomass organic Rankine cycle powered cascaded vapor compression-absorption system

In this paper, a novel solar-biomass organic Rankine cycle (ORC) powered cascaded vapor compression-absorption system is proposed for low temperature cooling applications. The proposed system achieves clean and efficient low temperature cooling and heating with zero dependency on fossil fuels. Thermo-economic analysis is reported to assess the performance and commercial viability of the system. The solar fraction and break-even point (BEP), considering paraboloid dish, n-pentane organic fluid, straw type biomass, and Jodhpur location, are calculated as 0.254 and 7.71 years, respectively. Due to lower annual efficiency, the solar fraction for the linear Fresnel reflector (LFR) based system is 0.179; however, the lower cost of LFR field and lower cost of energy generation from biomass leads to the lower BEP (7.43 years). Thermo-economic performance of the system is also affected by the ORC working fluid and the calculated break-even values are 7.85 years for Toluene and 8.16 years for R245fa. In comparison with the solar-biomass powered system, the fully biomass powered system achieves 39% lower capital cost and 30% lower BEP. The selection of the biomass is influenced by the calorific value and cost. The decision of selection between the proposed system and the equivalent stand-alone cooling and heating is influenced by the characteristics of solar field and biomass, ORC working fluid, electricity and process heat cost, location of installation, discount rate, cost of process heat and electricity.