Energy Conversion and Management最新文献_第4页

Optimization design of an adiabatic compressed air energy storage system with sliding pressure operation and packed bed thermal energy storage based on a one-dimensional loss model

IF 9.9 1区工程技术 Q1 ENERGY & FUELS

Energy Conversion and Management

Pub Date : 2025-02-12 DOI: 10.1016/j.enconman.2025.119626

Gangqiang Ge , Xuchao Cai , Hao Sun , Yufei Zhang , Huanran Wang , Ruixiong Li

In compressed air energy storage systems, the finite volume of the storage cavern leads to substantial variations in the pressure of the compressed air throughout the operational process. Operating the compressor and expander in sliding pressure mode can effectively reduce exergy losses associated with throttling, thereby improving the overall efficiency of the system. However, in sliding pressure operation mode, the increase in the compressor’s outlet temperature introduces substantial exergy losses in traditional dual-tank thermal energy storage due to the mixing of fluids at different temperatures. This study proposes an adiabatic compressed air energy storage system that integrates sliding pressure operation with packed bed thermal energy storage. A one-dimensional loss model for the compressor is developed, enabling an analysis of the coupling characteristics under sliding pressure conditions. The developed one-dimensional loss model demonstrates significantly improved accuracy over the general performance model. The optimized compressor, employing inlet guide vane adjustment, mass flow control, and speed regulation, achieves an adiabatic efficiency of over 84.4% under off-design conditions. Furthermore, the packed bed thermal energy storage in sliding pressure mode has higher efficiency compared to constant pressure operation. Among the various configurations analyzed, the integration of sliding pressure operation with packed bed thermal energy storage demonstrates the highest round trip efficiency of 72.6%, achieving an improvement of 11.6%.

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引用次数: 0

A novel sorption reactor for sorption heat transformers: Thermal energy storage system

IF 9.9 1区工程技术 Q1 ENERGY & FUELS

Energy Conversion and Management

Pub Date : 2025-02-10 DOI: 10.1016/j.enconman.2025.119618

Salman Hassanabadi, Ilya S. Girnik, Milad Ebadi, Majid Bahrami

This study addresses some of the critical limitations of current sorption heat transformer systems, particularly their cost, size and weight, which hinder their widespread adoption in various applications. A novel shell-and-tube sorption reactor design was proposed, featuring a lightweight shell instead of the conventional vacuum chambers typically used to encase the sorption reactor. In the proposed design, the sorbent material, synthesized in a disk-shaped form, was placed inside the tubes, while the heat transfer fluid flowed between the shell and the tubes. Comprehensive material characterization, including thermal diffusivity measurement, thermogravimetry, and porosimetry, was performed on the sorption materials. A proof-of-concept demonstration lab-scale prototype was designed, built, and tested. Using the disk-shaped composite, a significantly more active sorption composite per available volume was installed in the proposed sorption reactor which increased the energy storage density, while reducing the complexity and the cost of the system. Calorimetric large pressure jump tests on the proposed sorption reactor have shown a 0.74 MJ/kg energy storage density, a coefficient of performance for heating of 0.98 for 20-minute cycle time (1.4 for 90-minute cycle time), and specific power of 267 W/kg (20-min cycle time) for a 4.3 dm³ module under the nominal operating conditions of 90 °C, 30 °C, 30 °C, 15 °C, desorption, sorption, condenser, evaporator, respectively; where there is considerable room for performance improvement in the current sorption reactor. Considering that the energy density range for lithium-ion batteries is 0.46–0.72 MJ/kg, this demonstrates the competitiveness of thermal storage, particularly in comparison to the more expensive lithium-ion batteries.

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引用次数: 0

Numerical analysis and performance investigation of holographic spectrum-splitting concentrated photovoltaic-thermoelectric hybrid system with phase change material

IF 9.9 1区工程技术 Q1 ENERGY & FUELS

Energy Conversion and Management

Pub Date : 2025-02-10 DOI: 10.1016/j.enconman.2025.119571

Yue Hu , Piaopiao Li , Yucheng Yao , Hui Lv , Cheng Xu

To address the fluctuating nature of solar energy and achieve full spectrum utilization, a novel holographic spectrum-splitting concentration photovoltaic-thermoelectric hybrid system with phase change material is proposed in this study. Specifically, a two-layer volume holographic grating splitter is designed to separate the targeted spectrum from incident solar radiation for three spatially separated photovoltaic cells, while the thermoelectric module is employed to recover the residual heat from photovoltaic cells for electricity generation subsequently. Then, a heat storage layer with paraffin is positioned between the photovoltaic cells and the thermoelectric module to stabilize the temperature fluctuation and prolong the operation time for thermoelectric module. Thus, the conversion efficiency of solar to power can be significantly enhanced and a stable power supply is achieved by the proposed system. A thermodynamic mathematic model is established in this study, and the energy, exergy, and economic analysis are conducted comprehensively. The results show that under optimum conditions, the total energy and exergy efficiency of the proposed system reaches 30.2 % and 32.4 %, respectively. Among all components, the heat sink for thermoelectric module is the most inefficient component and highest exergy destruction is observed in the photovoltaic cells.

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引用次数: 0

Multi-Objective optimization and thermodynamic analysis of a supercritical CO2 Brayton cycle in a solar-powered multigeneration plant for net-zero emission goals

IF 9.9 1区工程技术 Q1 ENERGY & FUELS

Energy Conversion and Management

Pub Date : 2025-02-08 DOI: 10.1016/j.enconman.2025.119628

Veli Bakırcıoğlu , Hossein B. Jond , Fatih Yilmaz

The development, design, examination, and optimization of carbon-free power generation models are essential to achieve a sustainable future with net-zero emissions. This study introduces a novel multigeneration system, uniquely combining a supercritical CO₂ Brayton cycle and a transcritical CO₂ Rankine cycle, supported by a solar parabolic trough collector. The system integrates a reverse osmosis desalination unit, enabling simultaneous production of clean water, heating, and power. A multi-objective optimization framework is implemented by the NSGA-II algorithm, coupled with the TOPSIS method, to explore and identify optimal operational conditions. The innovation lies in the comprehensive consideration of solar incident angles and their impact on system performance, a rarely addressed aspect in the literature. Detailed thermodynamic analysis highlights system performance, achieving a net power capacity of 1052 kW, freshwater generation of 90.44 m3/h, and hot water generation of 1614 kW. The optimized results demonstrate significant improvements in overall energy (50.28 %) and exergy efficiency (22.31 %), showcasing the system’s potential as a benchmark for sustainable, zero-emission energy solutions.

无碳发电模式的开发、设计、检验和优化对于实现净零排放的可持续未来至关重要。本研究介绍了一种新型多发电系统，它独特地将超临界二氧化碳布雷顿循环和跨临界二氧化碳朗肯循环结合在一起，并由太阳能抛物槽集热器提供支持。该系统集成了一个反渗透海水淡化装置，可同时生产清洁水、供热和发电。通过 NSGA-II 算法和 TOPSIS 方法实现了多目标优化框架，以探索和确定最佳运行条件。创新之处在于全面考虑了太阳入射角及其对系统性能的影响，这在文献中很少涉及。详细的热力学分析凸显了系统性能，实现了 1052 千瓦的净发电量、90.44 立方米/小时的淡水发电量和 1614 千瓦的热水发电量。优化结果表明，总体能效（50.28%）和放能效率（22.31%）均有显著提高，展示了该系统作为可持续零排放能源解决方案基准的潜力。

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引用次数: 0

A comprehensive review of the evolution of biodiesel production technologies

IF 9.9 1区工程技术 Q1 ENERGY & FUELS

Energy Conversion and Management

Pub Date : 2025-02-08 DOI: 10.1016/j.enconman.2025.119623

Mehedi Hassan Pranta, Haeng Muk Cho

Biodiesel, compatible with compression ignition engines, is a promising alternative to fossil fuels due to its renewable and environmentally friendly nature. However, the high cost of biodiesel production stems from inefficiencies in industrial processes. This review summarizes the recent developments in advanced biodiesel synthesis techniques, evaluating various catalysts, including homogeneous, heterogeneous, biocatalysts, nanocatalysts, and ionic liquids, alongside factors such as feedstock generations, lipid content, and operating conditions affecting biodiesel yield. Third-generation feedstocks, particularly algae, demonstrate superior energy and oil content and eco-friendly characteristics. Among the techniques, supercritical transesterification shows significant potential for enhanced production. Methanol-based transesterification remains the most cost-effective and efficient method for commercial biodiesel synthesis. The study also analyzes various uncertainty methods and emphasizes the importance of continued innovation, including genetic engineering, to advance biodiesel production and foster its adoption as a sustainable energy source for a cleaner future.

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引用次数: 0

Well-to-Pump life cycle Assessment of methanol derived from high ash Coal, natural Gas, and municipal solid waste

IF 9.9 1区工程技术 Q1 ENERGY & FUELS

Energy Conversion and Management

Pub Date : 2025-02-08 DOI: 10.1016/j.enconman.2025.119573

Srijit Biswas, Arpit Yadav, Avinash Kumar Agarwal

With growing energy needs and the increasing threat of climate change, it becomes necessary to study the impact and feasibility of alternative fuels compared to conventional fossil fuels. One such alternative fuel is Methanol, which is also used widely in the chemical and pharmaceutical industries. It can be blended with gasoline/ diesel or used as 100% Methanol. Conventionally, Methanol is produced from natural gas. This pathway’s viability is investigated in the Indian context and compared with other pathways in this study. This study assesses the life cycle environmental and economic impact of Methanol production (by thermal partial oxidation methods) from municipal solid waste and high-ash Indian coal. It shows insights into integrating green hydrogen produced from the electrolysis of water using renewable energy (solar photovoltaic, in this study) pathways. This study considers seven scenarios based on feedstocks, integration of green hydrogen and the avoided emissions from the municipal solid waste. Using municipal solid waste with green hydrogen integration is found to have a positive environmental impact by reducing greenhouse gas emissions by 2.4 times compared to natural gas, which is a positive step in the direction of attaining “Net Zero” goals. The high-ash coal pathway without green hydrogen integration exhibited the most environmental impact (∼2.9 times compared to natural gas). The high ash coal pathway emissions could be reduced by 86% from the current scenario by integrating green hydrogen into the production stage, bringing the overall emissions to a level comparable to the natural gas pathway.

{"title":"Well-to-Pump life cycle Assessment of methanol derived from high ash Coal, natural Gas, and municipal solid waste","authors":"Srijit Biswas, Arpit Yadav, Avinash Kumar Agarwal","doi":"10.1016/j.enconman.2025.119573","DOIUrl":"10.1016/j.enconman.2025.119573","url":null,"abstract":"<div><div>With growing energy needs and the increasing threat of climate change, it becomes necessary to study the impact and feasibility of alternative fuels compared to conventional fossil fuels. One such alternative fuel is Methanol, which is also used widely in the chemical and pharmaceutical industries. It can be blended with gasoline/ diesel or used as 100% Methanol. Conventionally, Methanol is produced from natural gas. This pathway’s viability is investigated in the Indian context and compared with other pathways in this study. This study assesses the life cycle environmental and economic impact of Methanol production (by thermal partial oxidation methods) from municipal solid waste and high-ash Indian coal. It shows insights into integrating green hydrogen produced from the electrolysis of water using renewable energy (solar photovoltaic, in this study) pathways. This study considers seven scenarios based on feedstocks, integration of green hydrogen and the avoided emissions from the municipal solid waste. Using municipal solid waste with green hydrogen integration is found to have a positive environmental impact by reducing greenhouse gas emissions by 2.4 times compared to natural gas, which is a positive step in the direction of attaining “Net Zero” goals. The high-ash coal pathway without green hydrogen integration exhibited the most environmental impact (∼2.9 times compared to natural gas). The high ash coal pathway emissions could be reduced by 86% from the current scenario by integrating green hydrogen into the production stage, bringing the overall emissions to a level comparable to the natural gas pathway.</div></div>","PeriodicalId":11664,"journal":{"name":"Energy Conversion and Management","volume":"327 ","pages":"Article 119573"},"PeriodicalIF":9.9,"publicationDate":"2025-02-08","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143351297","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Design of lightweight hydraulic power unit for legged robots based on the Sobol sensitivity analysis

IF 9.9 1区工程技术 Q1 ENERGY & FUELS

Energy Conversion and Management

Pub Date : 2025-02-08 DOI: 10.1016/j.enconman.2025.119620

Bin Yu, Huashun Li, Chengze Gu, Ao Shen, Shuai Zhang, Xu Liu, Jingbin Li, Kaixian Ba, Guoliang Ma, Xiangdong Kong

Reducing the weight of the legged robot improves its endurance, maneuverability, and carrying capacity, enabling it to perform more complex tasks, such as transitioning from walking on flat terrain to executing challenging jumps. As the core energy source of a hydraulic legged robot, the weight of hydraulic power unit (HPU) accounts for more than 50% of the entire robot, offering significant potential for weight reduction. However, the design and sizeing parameters of the HPU are complex, and the key factors influencing its weight are not fully unclear, making targeted optimization challenging. To solve the above problems, this paper designs a lightweight hydraulic power unit (LHPU) for the legged robot based on the Sobol sensitivity analysis method. First, a weight model for the LHPU’s key components is established, and the key parameters influencing its weight are determined using the Sobol sensitivity analysis method. Then, key parameters matching is optimized for the motor-pump, and design improvements are made to components like the low-pressure tank, filter, and integrated block. Finally, the LHPU is tested for static and dynamic characteristics. The findings demonstrate that the LHPU can stabilize the required pressure and flow outputs for the legged robot and achieve a weight reduction exceeding 40%. This research offers significant insights for the lightweight design of advanced mobile systems, enhancing energy efficiency, mobility, and load capacity.

{"title":"Design of lightweight hydraulic power unit for legged robots based on the Sobol sensitivity analysis","authors":"Bin Yu, Huashun Li, Chengze Gu, Ao Shen, Shuai Zhang, Xu Liu, Jingbin Li, Kaixian Ba, Guoliang Ma, Xiangdong Kong","doi":"10.1016/j.enconman.2025.119620","DOIUrl":"10.1016/j.enconman.2025.119620","url":null,"abstract":"<div><div>Reducing the weight of the legged robot improves its endurance, maneuverability, and carrying capacity, enabling it to perform more complex tasks, such as transitioning from walking on flat terrain to executing challenging jumps. As the core energy source of a hydraulic legged robot, the weight of hydraulic power unit (HPU) accounts for more than 50% of the entire robot, offering significant potential for weight reduction. However, the design and sizeing parameters of the HPU are complex, and the key factors influencing its weight are not fully unclear, making targeted optimization challenging. To solve the above problems, this paper designs a lightweight hydraulic power unit (LHPU) for the legged robot based on the Sobol sensitivity analysis method. First, a weight model for the LHPU’s key components is established, and the key parameters influencing its weight are determined using the Sobol sensitivity analysis method. Then, key parameters matching is optimized for the motor-pump, and design improvements are made to components like the low-pressure tank, filter, and integrated block. Finally, the LHPU is tested for static and dynamic characteristics. The findings demonstrate that the LHPU can stabilize the required pressure and flow outputs for the legged robot and achieve a weight reduction exceeding 40%. This research offers significant insights for the lightweight design of advanced mobile systems, enhancing energy efficiency, mobility, and load capacity.</div></div>","PeriodicalId":11664,"journal":{"name":"Energy Conversion and Management","volume":"328 ","pages":"Article 119620"},"PeriodicalIF":9.9,"publicationDate":"2025-02-08","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143351042","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Desiccant wheel combined with dual separated or single integrated heat pump? A comparison on energy consumption

IF 9.9 1区工程技术 Q1 ENERGY & FUELS

Energy Conversion and Management

Pub Date : 2025-02-08 DOI: 10.1016/j.enconman.2025.119624

Hequn Liu , Yining Geng , Shaochen Tian , Yafeng Gao , Xing Su

Heat pump combined desiccant wheel systems have significant potential for industrial dehumidification. This study aims to define the usage boundaries between desiccant wheel systems combined with dual separated or single integrated heat pumps by selecting the most energy-efficient system configuration under various conditions. Two simulation models are developed to evaluate energy consumption under typical summer conditions. Moreover, Harbin, Beijing, Shanghai, Guangzhou, and Kunming are selected as representative cities to compare the energy consumption of two systems across five typical climate zones: severe cold regions, cold regions, hot summer/cold winter regions, hot summer/mild winter regions, and temperate regions. Meanwhile, the energy consumption of the two systems is compared under three indoor humidity control targets of 40 %, 30 %, and 20 %, and four indoor cooling load conditions ranging from 15 to 30 kW. The results indicate that the Single-HP system has lower energy consumption in severe cold, cold, hot summer/cold winter, and hot summer/mild winter regions, while the Dual-HP system is more suitable for climate zones with a lower outdoor humidity ratio. Moreover, the Single-HP system saves more energy when the indoor relative humidity is controlled below 20 %, while the Dual-HP system is more efficient under more relaxed humidity control requirements. In addition, regardless of indoor cooling load conditions, the Single-HP system consistently consumes less energy than the Dual-HP system with the energy consumption gap widening as the cooling load increases.

{"title":"Desiccant wheel combined with dual separated or single integrated heat pump? A comparison on energy consumption","authors":"Hequn Liu , Yining Geng , Shaochen Tian , Yafeng Gao , Xing Su","doi":"10.1016/j.enconman.2025.119624","DOIUrl":"10.1016/j.enconman.2025.119624","url":null,"abstract":"<div><div>Heat pump combined desiccant wheel systems have significant potential for industrial dehumidification. This study aims to define the usage boundaries between desiccant wheel systems combined with dual separated or single integrated heat pumps by selecting the most energy-efficient system configuration under various conditions. Two simulation models are developed to evaluate energy consumption under typical summer conditions. Moreover, Harbin, Beijing, Shanghai, Guangzhou, and Kunming are selected as representative cities to compare the energy consumption of two systems across five typical climate zones: severe cold regions, cold regions, hot summer/cold winter regions, hot summer/mild winter regions, and temperate regions. Meanwhile, the energy consumption of the two systems is compared under three indoor humidity control targets of 40 %, 30 %, and 20 %, and four indoor cooling load conditions ranging from 15 to 30 kW. The results indicate that the Single-HP system has lower energy consumption in severe cold, cold, hot summer/cold winter, and hot summer/mild winter regions, while the Dual-HP system is more suitable for climate zones with a lower outdoor humidity ratio. Moreover, the Single-HP system saves more energy when the indoor relative humidity is controlled below 20 %, while the Dual-HP system is more efficient under more relaxed humidity control requirements. In addition, regardless of indoor cooling load conditions, the Single-HP system consistently consumes less energy than the Dual-HP system with the energy consumption gap widening as the cooling load increases.</div></div>","PeriodicalId":11664,"journal":{"name":"Energy Conversion and Management","volume":"328 ","pages":"Article 119624"},"PeriodicalIF":9.9,"publicationDate":"2025-02-08","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143351043","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Eco-friendly hydrogen and power co-production system with a flexible operational strategy

IF 9.9 1区工程技术 Q1 ENERGY & FUELS

Energy Conversion and Management

Pub Date : 2025-02-08 DOI: 10.1016/j.enconman.2025.119614

Taehyun Kim , Yungeon Kim , Jinwoo Park

Reducing the cost of clean hydrogen production is essential to combat global warming and advance the hydrogen economy. Integrating water electrolysis with complementary systems offers a promising approach to developing a hybrid hydrogen production framework. Therefore, this study aims to propose a hydrogen and power co-production system with a flexible operational strategy to reduce hydrogen production costs. This system operates through the integration of a proton exchange membrane electrolysis cell system with an Allam cycle for power generation. Additionally, it produces hydrogen through water electrolysis during off-peak periods and generates power using the Allam cycle during peak periods, adapting to fluctuations in electricity supply and demand. It demonstrates an energy efficiency of 56.24 % under standard design conditions and achieves up to 57.87 % efficiency when the water electrolyzer capacity is enhanced. Furthermore, it exhibits operational flexibility during both off-peak and peak periods, optimizing economic benefits. Economic analysis revealed a net present value of $626.4 million and an internal rate of return of 14.3 %. Finally, the system produces minimal carbon dioxide emissions, underscoring its significant environmental benefits. The proposed hydrogen and power co-production system is expected to contribute to the economic viability of clean hydrogen production and supports the hydrogen economy, establishing a foundation for eco-friendly energy systems.

{"title":"Eco-friendly hydrogen and power co-production system with a flexible operational strategy","authors":"Taehyun Kim , Yungeon Kim , Jinwoo Park","doi":"10.1016/j.enconman.2025.119614","DOIUrl":"10.1016/j.enconman.2025.119614","url":null,"abstract":"<div><div>Reducing the cost of clean hydrogen production is essential to combat global warming and advance the hydrogen economy. Integrating water electrolysis with complementary systems offers a promising approach to developing a hybrid hydrogen production framework. Therefore, this study aims to propose a hydrogen and power co-production system with a flexible operational strategy to reduce hydrogen production costs. This system operates through the integration of a proton exchange membrane electrolysis cell system with an Allam cycle for power generation. Additionally, it produces hydrogen through water electrolysis during off-peak periods and generates power using the Allam cycle during peak periods, adapting to fluctuations in electricity supply and demand. It demonstrates an energy efficiency of 56.24 % under standard design conditions and achieves up to 57.87 % efficiency when the water electrolyzer capacity is enhanced. Furthermore, it exhibits operational flexibility during both off-peak and peak periods, optimizing economic benefits. Economic analysis revealed a net present value of $626.4 million and an internal rate of return of 14.3 %. Finally, the system produces minimal carbon dioxide emissions, underscoring its significant environmental benefits. The proposed hydrogen and power co-production system is expected to contribute to the economic viability of clean hydrogen production and supports the hydrogen economy, establishing a foundation for eco-friendly energy systems.</div></div>","PeriodicalId":11664,"journal":{"name":"Energy Conversion and Management","volume":"327 ","pages":"Article 119614"},"PeriodicalIF":9.9,"publicationDate":"2025-02-08","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143351296","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Experimental investigation of an Auto-Switching SH TEG/PCM unit for consistent All-Day electric power generation

IF 9.9 1区工程技术 Q1 ENERGY & FUELS

Energy Conversion and Management

Pub Date : 2025-02-07 DOI: 10.1016/j.enconman.2025.119556

Jinglong Wang, Lin Lu, Kai Jiao, Miao Han

In the pursuit of sustainable energy solutions, combining a thermoelectric generator (TEG) with a phase change material (PCM) powered by solar energy shows promise for consistent electricity generation (EG). Despite extensive research on solar-heating TEG/PCM systems, there is a lack of studies directly utilizing sunlight, with heaters commonly used as substitutes, thus overlooking the influence of solar radiation spectrum and intensity. This study examines auto-switching SH TEG/PCM unit performance under simulated solar irradiation, presenting an experimental setup and theoretical model for system analysis. Results show that the total EG over 24 h relies on the EG during the lighted operation phase (LOP). Once the PCM in the aluminum box (AB) fully melts, a secondary temperature rise near the bottom of the top cover occurs during the transition to static phase (TSP). Unit 80-AB achieves the highest total EG under a total solar irradiance of 4 kW⋅h/m², with values of 3.72 and 0.15 W⋅h/m² for the LOP and TSP, and when exposed to 8 SSs for 5 h, it peaks at 4.4 and 0.19 W⋅h/m² for the LOP and TSP, respectively. Additionally, the EG for unit 80-AB is maximal after almost 10-hour exposure, with the insulated unit featuring a film achieving a total EG of 8.78 W⋅h/m², exceeding the bare unit and insulated unit by 1.06 and 1.54 W⋅h/m², respectively. During the LOP, the experimental unit 80-AB can achieve a maximum increase in EG of 7.71 W⋅h/m² in the bare mode compared to the control unit. The open-circuit voltage of unit 80-AB reaches approximately 110 mV, with the maximum output power amounting to 0.34 W/m² when the load resistance is 5 Ω. The proposed units present a practical solution for continuous EG throughout the day, guaranteeing a reliable energy provision and heralding an environmentally sustainable energy paradigm.

{"title":"Experimental investigation of an Auto-Switching SH TEG/PCM unit for consistent All-Day electric power generation","authors":"Jinglong Wang, Lin Lu, Kai Jiao, Miao Han","doi":"10.1016/j.enconman.2025.119556","DOIUrl":"10.1016/j.enconman.2025.119556","url":null,"abstract":"<div><div>In the pursuit of sustainable energy solutions, combining a thermoelectric generator (TEG) with a phase change material (PCM) powered by solar energy shows promise for consistent electricity generation (EG). Despite extensive research on solar-heating TEG/PCM systems, there is a lack of studies directly utilizing sunlight, with heaters commonly used as substitutes, thus overlooking the influence of solar radiation spectrum and intensity. This study examines auto-switching SH TEG/PCM unit performance under simulated solar irradiation, presenting an experimental setup and theoretical model for system analysis. Results show that the total EG over 24 h relies on the EG during the lighted operation phase (LOP). Once the PCM in the aluminum box (AB) fully melts, a secondary temperature rise near the bottom of the top cover occurs during the transition to static phase (TSP). Unit 80-AB achieves the highest total EG under a total solar irradiance of 4 kW⋅h/m<sup>2</sup>, with values of 3.72 and 0.15 W⋅h/m<sup>2</sup> for the LOP and TSP, and when exposed to 8 SSs for 5 h, it peaks at 4.4 and 0.19 W⋅h/m<sup>2</sup> for the LOP and TSP, respectively. Additionally, the EG for unit 80-AB is maximal after almost 10-hour exposure, with the insulated unit featuring a film achieving a total EG of 8.78 W⋅h/m<sup>2</sup>, exceeding the bare unit and insulated unit by 1.06 and 1.54 W⋅h/m<sup>2</sup>, respectively. During the LOP, the experimental unit 80-AB can achieve a maximum increase in EG of 7.71 W⋅h/m<sup>2</sup> in the bare mode compared to the control unit. The open-circuit voltage of unit 80-AB reaches approximately 110 mV, with the maximum output power amounting to 0.34 W/m<sup>2</sup> when the load resistance is 5 Ω. The proposed units present a practical solution for continuous EG throughout the day, guaranteeing a reliable energy provision and heralding an environmentally sustainable energy paradigm.</div></div>","PeriodicalId":11664,"journal":{"name":"Energy Conversion and Management","volume":"327 ","pages":"Article 119556"},"PeriodicalIF":9.9,"publicationDate":"2025-02-07","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143347382","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0