Imperial College London


Faculty of EngineeringDepartment of Chemical Engineering

Professor of Clean Energy Technologies



+44 (0)20 7594 1601c.markides Website




404ACE ExtensionSouth Kensington Campus






BibTex format

author = {Oyewunmi, OA and Lecompte, S and De, Paepe M and Markides},
publisher = {ECOS-2017},
title = {Thermodynamic Optimization of Recuperative Sub- and Transcritical Organic Rankine Cycle Systems},
url = {},
year = {2017}

RIS format (EndNote, RefMan)

AB - There is significant interest in the deployment of organic Rankine cycle (ORC) technology for waste-heatrecovery and power generation in industrial settings. This study considers ORC systems optimized formaximum power generation using a case study of an exhaust flue-gas stream at a temperature of 380 °C asthe heat source, covering over 30 working fluids and also considering the option of featuring a recuperator.Systems based on transcritical cycles are found to deliver higher power outputs than subcritical ones, withoptimal evaporation pressures that are 4-5 times the critical pressures of refrigerants and light hydrocarbons,and 1-2 times those of siloxanes and heavy hydrocarbons. For maximum power production, a recuperator isnecessary for ORC systems with constraints imposed on their evaporation and condensation pressures. Thisincludes, for example, limiting the minimum condensation pressure to atmospheric pressure to prevent subatmosphericoperation of this component, as is the case when employing heavy hydrocarbon and siloxaneworking fluids. For scenarios where such operating constraints are relaxed, the optimal cycles do not featurea recuperator, providing some capital cost savings, with some cycles showing more than three times thegenerated power than with this component, making investments in sub-atmospheric components worthwhile.
AU - Oyewunmi,OA
AU - Lecompte,S
AU - De,Paepe M
AU - Markides
PB - ECOS-2017
PY - 2017///
TI - Thermodynamic Optimization of Recuperative Sub- and Transcritical Organic Rankine Cycle Systems
UR -
ER -