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 = {Li, X and Tian, H and Shu, G and Zhao, M and Markides, C and Hu, C},
doi = {10.1016/j.apenergy.2019.05.082},
journal = {Applied Energy},
pages = {1581--1599},
title = {Potential of carbon dioxide transcritical power cycle waste-heat recovery systems for heavy-duty truck engines},
url = {},
volume = {250},
year = {2019}

RIS format (EndNote, RefMan)

AB - Carbon dioxide transcritical power cycle (CTPC) systems are considered a new and particularly interesting technology for waste-heat recovery. In heavy-duty truck engine applications, challenges arise from the highly transient nature of the available heat sources. This paper presents an integrated model of CTPC systems recovering heat from a truck diesel engine, developed in GT-SUITE software and calibrated against experimental data, considers the likely fuel consumption improvements and identifies directions for further improvement. The transient performance of four different CTPC systems is predicted over a heavy-heavy duty driving cycle with a control structure comprising a mode switch module and two PID controllers implemented to realize stable, safe and optimal operation. Three operating modes are defined: startup mode, power mode, and stop mode. The results demonstrate that CTPC systems are robust and able to operate safely even when the heat sources are highly transient, indicating a promising potential for the deployment of this technology in such applications. Furthermore, a system layout with both a preheater and a recuperator appears as the most promising, allowing a 2.3% improvement in brake thermal efficiency over the whole driving cycle by utilizing 48.9% of the exhaust and 72.8% of the coolant energy, even when the pump and turbine efficiencies are as low as 50%. Finally, factor analysis suggests that important directions aimed at improving the performance and facilitating CTPC system integration with vehicle engines are: 1) ensuring long-duration operation in power mode, e.g., by employment in long-haul trucks; and 2) enhancing pump and turbine performance.
AU - Li,X
AU - Tian,H
AU - Shu,G
AU - Zhao,M
AU - Markides,C
AU - Hu,C
DO - 10.1016/j.apenergy.2019.05.082
EP - 1599
PY - 2019///
SN - 0306-2619
SP - 1581
TI - Potential of carbon dioxide transcritical power cycle waste-heat recovery systems for heavy-duty truck engines
T2 - Applied Energy
UR -
UR -
VL - 250
ER -