Exergy analysis of biomass organic Rankine cycle for power generation

Abstract

The study examines proposed small biomass-fed Organic Rankine Cycle (ORC) power plant through exergy analysis. The system consists of combustion burner unit to utilize biomass as fuel, and organic Rankine cycle unit to produce power from the expander. The heat from combustion burner was transfered by thermal oil heater to evaporate ORC working fluid in the evaporator part. The effects of adding recuperator into exergy destruction were investigated. Furthermore, the results of the variations of system configurations with different operating parameters, such as the evaporating pressures, ambient temperatures, and expander pressures were analyzed. It was found that the largest exergy destruction occurs during processes are at combustion part, followed by evaporator, condenser, expander, and pump. The ORC system equipped with a recuperator unit exhibited good operational characteristics under wide range conditions compared to the one without recuperator.