Abdulrazzak Akroot¹, Kayser Aziz Ameen², Haitham M. Ibrahim³, Hasanain A. Abdul Wahhab^3,*, Miqdam T. Chaichan⁴

Energy Engineering, Vol.123, No.2, 2026, DOI:10.32604/ee.2025.073702 - 27 January 2026

Abstract Improving energy efficiency and lowering negative environmental impact through waste heat recovery (WHR) is a critical step toward sustainable cement manufacturing. This study analyzes advanced cogeneration systems for recovering waste heat from the Fallujah White Cement Plant in Iraq. The novelty of this work lies in its direct application and comparative thermodynamic analysis of three distinct cogeneration cycles—the Organic Rankine Cycle, the Single-Flash Steam Cycle, and the Dual-Pressure Steam Cycle—within the Iraqi cement industry, a context that has not been widely studied. The main objective is to evaluate and compare these models to determine the… More > Graphic Abstract

Zujun Ding, Shuaichao Wu, Chenliang Ji, Xinyu Feng, Yuanyuan Shi, Baolian Liu, Wan Chen, Qiuchan Bai, Hengrui Zhou, Hui Huang, Jie Ji^*

Energy Engineering, Vol.123, No.2, 2026, DOI:10.32604/ee.2025.068106 - 27 January 2026

Abstract In the quest to enhance energy efficiency and reduce environmental impact in the transportation sector, the recovery of waste heat from diesel engines has become a critical area of focus. This study provided an exhaustive thermodynamic analysis optimizing Organic Rankine Cycle (ORC) systems for waste heat recovery from diesel engines. The study assessed the performance of five candidate working fluids—R11, R123, R113, R245fa, and R141b—under a range of operating conditions, specifically varying overheat temperatures and evaporation pressures. The results indicated that the choice of working fluid substantially influences the system’s exergetic efficiency, net output power,… More >

S. Srinivasa senthil, K. Vijayakumar^*

Energy Engineering, Vol.122, No.12, pp. 5149-5173, 2025, DOI:10.32604/ee.2025.070889 - 27 November 2025

Abstract Heating, ventilation, and air conditioning (HVAC) systems contribute substantially to global energy consumption, while rejecting significant amounts of low-grade heat into the environment. This paper presents a non-intrusive spiral-coil heat exchanger designed to recover waste heat from the outdoor condenser of a split-type air conditioner. The system operates externally without altering the existing HVAC configuration, thereby rendering it suitable for retrofitting. Water was circulated as the working fluid at flow rates of 0.028–0.052 kg/s to assess thermal performance. Performance indicators, including the outlet water temperature, heat transfer rate, convective coefficient, and efficiency, were systematically evaluated.… More >

Linwei Yao^1,*, Xiangning Lin^1,2, Huashen He¹, Jiahui Yang¹

Energy Engineering, Vol.122, No.8, pp. 3285-3308, 2025, DOI:10.32604/ee.2025.066628 - 24 July 2025

Abstract In order to address the synergistic optimization of energy efficiency improvement in the waste incineration power plant (WIPP) and renewable energy accommodation, an electricity-hydrogen-waste multi-energy system integrated with phase change material (PCM) thermal storage is proposed. First, a thermal energy management framework is constructed, combining PCM thermal storage with the alkaline electrolyzer (AE) waste heat recovery and the heat pump (HP), while establishing a PCM-driven waste drying system to enhance the efficiency of waste incineration power generation. Next, a flue gas treatment method based on purification-separation-storage coordination is adopted, achieving spatiotemporal decoupling between waste incineration… More >

Guowei Li^1,*, Shujuan Bu², Xinle Yang², Kaijie Liang¹, Zhengri Shao¹, Xiaobei Song¹, Yitian Tang³, Dejing Zong⁴

Energy Engineering, Vol.121, No.12, pp. 3843-3874, 2024, DOI:10.32604/ee.2024.056195 - 22 November 2024

Abstract A novel dual-pressure organic Rankine cycle system (DPORC) with a dual-stage ejector (DE-DPORC) is proposed. The system incorporates a dual-stage ejector that utilizes a small amount of extraction steam from the high-pressure expander to pressurize a large quantity of exhaust gas to perform work for the low-pressure expander. This innovative approach addresses condensing pressure limitations, reduces power consumption during pressurization, minimizes heat loss, and enhances the utilization efficiency of waste heat steam. A thermodynamic model is developed with net output work, thermal efficiency, and exergy efficiency (W_net, η_t, η_ex) as evaluation criteria, an economic model is established… More >

Wenxia Zhu^*, Baishu Chen, Lexin Wang, Chunxiang Wang

Frontiers in Heat and Mass Transfer, Vol.22, No.5, pp. 1559-1573, 2024, DOI:10.32604/fhmt.2024.047351 - 30 October 2024

Abstract A Solid Oxide Fuel Cell (SOFC) is an electrochemical device that converts the chemical energy of a substance into electrical energy through an oxidation-reduction mechanism. The electrochemical reaction of a solid oxide fuel cell (SOFC) generates heat, and this heat can be recovered and put to use in a waste heat recovery system. In addition to preheating the fuel and oxidant, producing steam for industrial use, and heating and cooling enclosed rooms, this waste heat can be used for many more productive uses. The large waste heat produced by SOFCs is a worry that must… More >

Yuming Zhao¹, Jing Wang¹, Bin Sun², Zhenshang Wang¹, Huashan Li², Jiongcong Chen^2,*

Frontiers in Heat and Mass Transfer, Vol.22, No.4, pp. 1171-1188, 2024, DOI:10.32604/fhmt.2024.054594 - 30 August 2024

Abstract Data centers (DCs) are highly energy-intensive facilities, where about 30%–50% of the power consumed is attributable to the cooling of information technology equipment. This makes liquid cooling, especially in two-phase mode, as an alternative to air cooling for the microprocessors in servers of interest. The need to meet the increased power density of server racks in high-performance DCs, along with the push towards lower global warming potential (GWP) refrigerants due to environmental concerns, has motivated research on the selection of two-phase heat transfer fluids for cooling servers while simultaneously recovering waste heat. With this regard,… More >

T. E. Boukelia^1,2,*, A. Bourouis¹, M. E. Abdesselem³, M. S. Mecibah³

Energy Engineering, Vol.120, No.11, pp. 2449-2467, 2023, DOI:10.32604/ee.2023.030183 - 31 October 2023

Abstract Concentrating Solar Power (CSP) plants offer a promising way to generate low-emission energy. However, these plants face challenges such as reduced sunlight during winter and cloudy days, despite being located in high solar radiation areas. Furthermore, their dispatch capacities and yields can be affected by high electricity consumption, particularly at night. The present work aims to develop an off-design model that evaluates the hourly and annual performances of a parabolic trough power plant (PTPP) equipped with a waste heat recovery system. The study aims to compare the performances of this new layout with those of… More >

Ali Jaber Abdulhamed^1,*, Aws Al-Akam¹, Ahmed A. Abduljabbar², Mohammed H. Alkhafaji³

Energy Engineering, Vol.120, No.8, pp. 1729-1746, 2023, DOI:10.32604/ee.2023.029069 - 05 June 2023

Abstract Thermoelectric generators (TEGs) are considered promising devices for waste heat recovery from various systems. The Seebeck effect can be utilized to generate power using the residual heat emitted by the filter dryer receiver (FDR) of an air conditioning (A/C) system, which would otherwise go to waste. The study aims to build a set of thermoelectric generators (TEG) to collect the waste heat of the FDR and generate low-power electricity. A novel electrical circuit with two transformers is designed and fabricated to produce a more stable voltage for operation and charging. The thermoelectric generator (TEGs) was… More >

Liqing Yan¹, Jiang Liu^1,2,*, Guangwei Ying³, Ning Zhang⁴

Energy Engineering, Vol.120, No.8, pp. 1919-1938, 2023, DOI:10.32604/ee.2023.027546 - 05 June 2023

Abstract Recovery of waste heat from boiler flue gas is an effective way to improve energy utilization efficiency. Taking a heating station heating project as an example, the existing heating system of this heating station was analyzed for its underutilized flue gas waste heat and low energy utilization rate. Rankine cycle is an effective waste heat recovery method, and a steam boiler organic Rankine cycle (ORC) cogeneration waste heat utilization method is proposed. The system model simulation is constructed and verified. First, a thermodynamic model was constructed in MATLAB and five suitable work gases were selected More > Graphic Abstract