Comparative Evaluation of Energy Recovery Systems for Enhanced Automotive Overall Efficiency

Jingxing Liu; Cexiao Hu; Qixuan Qiu; Junyi Kang; Xuetianfu Peng

doi:10.54254/2755-2721/2026.KA27455

Applied and Computational EngineeringOpen access

Comparative Evaluation of Energy Recovery Systems for Enhanced Automotive Overall Efficiency

Research Article

Open Access

Comparative Evaluation of Energy Recovery Systems for Enhanced Automotive Overall Efficiency

Jingxing Liu ^1* Cexiao Hu ², Qixuan Qiu ³, Junyi Kang ⁴, Xuetianfu Peng ⁵

¹ Wuhan University of Technology

² Gonzaga University

³ Wuhan University of Technology

⁴ Zhejiang University

⁵ eijing Information Science and Technology University

^*Corresponding author: 340459@whut.edu.cn

Published on 2 October 2025

ACE Vol.188

ISSN (Print): 2755-273X

ISSN (Online): 2755-2721

ISBN (Print): 978-1-80590-397-0

ISBN (Online): 978-1-80590-398-7

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Abstract

The rapid growth of the global automotive industry has led to increased fuel consumption and significant environmental challenges, particularly in the form of CO₂ emissions. Energy recovery systems (ERSs) offer a promising solution to improve vehicle efficiency and reduce environmental impact. This paper evaluates five prominent energy recovery methods: regenerative braking, mechanical flywheel, thermoelectric recovery, Rankine cycle, and electric turbocharger, to determine their effectiveness in reducing fuel consumption and enhancing energy efficiency. Through a comprehensive review of experimental and simulation-based studies, each method is analyzed under various driving conditions, including urban, highway, and other cycles. Results indicate that the Rankine cycle achieves the highest theoretical efficiency (peak 23.7%, average 5.50%) under stable high-speed conditions, while regenerative braking excels in urban settings with frequent deceleration (38.8–54.2% recovery efficiency). Mechanical flywheels show strong performance in high-power transients (up to 39% fuel savings), whereas thermoelectric and electric turbocharger systems provide more modest gains. The study concludes that the optimal energy recovery strategy is highly dependent on specific driving conditions, and selection of the most appropriate technology should be based on the predominant operational profile of the vehicle.

Keywords:

Energy Recovery Systems, Automotive Overall Efficiency, Kinetic Energy Recovery, Waste Heat Recovery, Fuel Consumption Reduction

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