Energy Conversion and Management最新文献

{"title":"Study on performance of a multi-heat source heat pump coupled energy storage system for plant factory heating system","authors":"","doi":"10.1016/j.enconman.2024.118917","DOIUrl":"10.1016/j.enconman.2024.118917","url":null,"abstract":"<div><p>CO₂ air source heat pump (CASHP) faces challenges of performance degradation caused by the high return water temperature and the low ambient temperature for building heating. This study proposed a novel multi-heat source heat pump system (MHSHP) that combined with a CO₂ air source heat pumps (CASHP) and ground source heat pumps (GSHP) with the implementation of a thermal storage tank. The performance and CO₂ emissions of both CASHP and MHSHP systems were investigated by applying a plant factory located in Beijing, China. The effects of user-side parameters and ambient temperature were explored with the storage water temperatures ranging from 20 °C to 40 °C. The results demonstrated that the heating performance of the CASHP improved with an increase of user water flow rate and ambient temperatures, while it decreased as the storage water temperature increased. At the flow rate of 1.1 m³/h, the increase of the compressor frequency from 40 Hz to 60 Hz led to a significant improvement in heating capacity by 53.3 %, and a reduction in COP by 23.3 %. When the user-side water flow ratio decreased or the total flow rate increased, the COP of the MHSHP system showed improvement and outperformed that of the CASHP system, with an increase ranging from 46.9 % to 61.5 %. Additionally, it exhibits reduced sensitivity to ambient temperature fluctuations, resulting in a decrease in COP variability from 33.3 % to 20.6 %. Moreover, the CO₂ emissions of the system decrease as the COP increases, with significant reduction of 69.2 %.</p></div>","PeriodicalId":11664,"journal":{"name":"Energy Conversion and Management","volume":null,"pages":null},"PeriodicalIF":9.9,"publicationDate":"2024-08-15","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141993407","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}

{"title":"Modelling and optimization of concentrated solar power using response surface methodology: A comparative study of air, water, and hybrid cooling techniques","authors":"","doi":"10.1016/j.enconman.2024.118915","DOIUrl":"10.1016/j.enconman.2024.118915","url":null,"abstract":"<div><p>This research introduces a novel approach specifically designed to improve the design of Concentrated Solar Power plants utilizing the Response Surface Methodology. The objective of the suggested methodology is to enhance energy production efficiency by simultaneously minimizing the levelized cost of electricity and the land footprint associated with the power plant while comparing three different cooling techniques: air, water, and hybrid. Two software tools, System Advisor Model and Design-Expert, are employed to validate the primary model, evaluate the responses, generate the predictive models, and verify the results. The configuration of a Concentrated Solar Power plant is influenced by four main factors: the size of the solar field (solar multiple), row spacing, number of solar assemblies per loop, and size of thermal energy storage. In this study, these factors are varied within the following ranges: solar multiple from 1 to 5, row spacing from 10 to 30 m, number of solar assemblies from 4 to 10 per loop, and thermal energy storage from 5 to 15 h. The generated predictive models demonstrated very high accuracy, particularly for the annual energy production, with an error ranging between 0.2% and 1.5%. The findings showed that the hybrid cooling system is the most cost-effective cooling technique and has the highest energy output compared to the evaporative and air-cooling methods. When optimizing the required area of the hybrid cooled plant with a reduction of 47.44%, the analysis indicated a minimal decrease in energy output of 3.61% and a slight increase in the levelized cost of electricity by 0.95%. According to the results, the effect of area on the annual energy production and levelized cost of electricity is significant below the optimal area, while this effect becomes minor at higher values.</p></div>","PeriodicalId":11664,"journal":{"name":"Energy Conversion and Management","volume":null,"pages":null},"PeriodicalIF":9.9,"publicationDate":"2024-08-15","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141993363","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}

{"title":"A feasibility study on the use of glycerol as a solution to waste renewable energy storage in the United Kingdom","authors":"","doi":"10.1016/j.enconman.2024.118873","DOIUrl":"10.1016/j.enconman.2024.118873","url":null,"abstract":"<div><p>This study has analysed to feasibility of incorporating a biologically derived liquid organic hydrogen carrier (LOHC) into the energy grid as a method of reducing waste renewable energy.</p><p>With this goal in mind, a scenario has been devised in using glycerol to transport hydrogen for release at domestic homes for use in PEM fuel cells. Through this, a packed bed reactor can fulfil the average load with a glycerol conversion of 94 %. The peak load can be fulfilled by using 3 of these reactors at each home and reducing the temperature to decrease conversion when the energy is not needed. Through the dehydrogenation, many side products are formed, including methanol and ethanol which can be used to regenerate glycerol in a transesterification reaction. For a target conversion of 98 %, a 7.08 m³ reactor vessel would be required to handle the alcohol output of 100 houses.</p><p>After these simulations, an economic analysis and life cycle assessment was performed. The economic showed operating costs to be around 76.5 $/h, and the capital cost per home to be $33,000. 60% of this investment is the cost of the catalyst used in the dehydrogenation of glycerol. An alternative catalyst is required to reduce this total cost. The life cycle assessment showed very high effectiveness in reducing carbon missions, however, the other pollutants severely damper its viability.</p></div>","PeriodicalId":11664,"journal":{"name":"Energy Conversion and Management","volume":null,"pages":null},"PeriodicalIF":9.9,"publicationDate":"2024-08-15","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.sciencedirect.com/science/article/pii/S0196890424008148/pdfft?md5=2cd5e35216018cc890726172960408bf&pid=1-s2.0-S0196890424008148-main.pdf","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141993360","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Assessing the environmental and economic sustainability of emerging tandem photovoltaic technologies in China","authors":"","doi":"10.1016/j.enconman.2024.118890","DOIUrl":"10.1016/j.enconman.2024.118890","url":null,"abstract":"<div><p>Tandem cell technologies with high conversion efficiency are considered promising options for a future photovoltaics (PV) market. Several studies have assessed the environmental and economic impacts of tandem technologies in European countries; however, such studies are not available for China, the largest PV market in the world. To fill this research gap, this paper presents a comprehensive life cycle environmental and economic assessment of solar electricity in China generated by two emerging PV tandem technologies: 4-terminal gallium arsenide/silicon heterojunction (GaAs/SHJ) and perovskite/silicon with tunnel oxide passivated contact (PSC/TOPCon). The study uses life cycle assessment (LCA) to evaluate the environmental impacts and life cycle costing (LCC) to assess the economic aspects of both technologies as such studies are not available in the literature. The LCA results reveal that electricity from the GaAs/SHJ tandem PV (based on reusing GaAs wafer five times) has 2–5 times higher impacts than electricity from PSC/TOPCon in most of the 18 impact categories considered, owing to high material and energy consumption for GaAs manufacturing. For example, the climate change potential of the GaAs/SHJ system (127 kg CO₂ eq./MWh) is more than 3.5 times higher than that of PSC/TOPCon (33.5 kg CO₂ eq./MWh). However, if the GaAs wafer were reused 100 times, then the climate change and all other impacts of GaAs/SHJ would become lower (1–26 %) than those of PSC/TOPCon, except for metal depletion which would still be significantly (126 %) higher. The life cycle costs of electricity generation by GaAs/SHJ are also much higher (135 $/MWh) than those of PSC/TOPCon (23.7 $/MWh), with arsine and gallium accounting for 68 % of the total cost in the GaAs/SHJ system. As these two technologies are currently at an early stage of development, further developments to reduce the material and energy consumption, as well as improve the efficiency and recyclability of both systems, are essential for future cost-effective and low-impact solar electricity generation in China.</p></div>","PeriodicalId":11664,"journal":{"name":"Energy Conversion and Management","volume":null,"pages":null},"PeriodicalIF":9.9,"publicationDate":"2024-08-15","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.sciencedirect.com/science/article/pii/S0196890424008318/pdfft?md5=fdadd0eb09d40c5ca038c7e6165cf557&pid=1-s2.0-S0196890424008318-main.pdf","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141990979","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Corrigendum to “Optimal design of on-site PV-based battery grid-tied green hydrogen production system” [Energ. Convers. Manage. 307 (2024) 118378]","authors":"","doi":"10.1016/j.enconman.2024.118905","DOIUrl":"10.1016/j.enconman.2024.118905","url":null,"abstract":"","PeriodicalId":11664,"journal":{"name":"Energy Conversion and Management","volume":null,"pages":null},"PeriodicalIF":9.9,"publicationDate":"2024-08-15","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.sciencedirect.com/science/article/pii/S019689042400846X/pdfft?md5=846d915cc495d7cdfba280177b919809&pid=1-s2.0-S019689042400846X-main.pdf","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141993362","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Integrated approach for co-production of bioethanol and light aromatics from lignocellulose through polyethylene glycol-aided acidic glycerol pretreatment","authors":"","doi":"10.1016/j.enconman.2024.118896","DOIUrl":"10.1016/j.enconman.2024.118896","url":null,"abstract":"<div><p>Acid-catalyzed glycerol organosolv (GO) pretreatment is a promising method for lignocellulosic biomass (LCB) fractionation. However, this method often leads to lignin repolymerization, intensifying lignin's inhibitory effects on subsequent enzymatic hydrolysis and limiting the production of highly active lignin, thereby hindering its valorization. This study explored incorporating polyethylene glycol (PEG) into acidic-catalyzed GO to improve bioethanol and bio-oil yields, with a focus on improving the yield of light aromatics, from LCB. Optimized PEG-aided GO pretreatment achieved a significantly higher bioethanol yield (23.7 g/L) compared to GO (17 g/L) and dilute acid (DA: 11.3 g/L) pretreatments. This improvement is attributed to the ability of PEG to mitigate lignin inhibition and modify the physicochemical properties of the pretreated substrate. Furthermore, thermal pyrolysis of PEG-aided GO lignin, obtained after the fermentation process, resulted in a substantially increased bio-oil yield (45.5 %) compared to GO (19 %) and DA (12 %). The enhanced bio-oil yield from PEG-aided GO lignin is ascribed to the promotion of β-O-4 linkages and the formation of β-O-4′ linkages. Characterization of the pyrolysis bio-oil revealed that light aromatic compounds were the dominant fraction, with their relative abundance significantly increasing from DA (5.9 %) to GO (9.7 %) and PEG-aided GO lignin (24.9 %). The PEG-aided GO method achieved an energy output of 8.85 MJ/kg, exceeding that of the GO and DA methods by 31 % and 57 %, respectively. The energy conversion efficiency of the PEG-aided GO method was 70 %, demonstrating a significant improvement compared to GO (57 %) and DA (51 %). This approach promotes the circular economy by upcycling LCB for bioethanol and valuable light aromatic compound production.</p></div>","PeriodicalId":11664,"journal":{"name":"Energy Conversion and Management","volume":null,"pages":null},"PeriodicalIF":9.9,"publicationDate":"2024-08-14","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141993359","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}

{"title":"Sustainability of biomass pyrolysis for bio-aromatics and bio-phenols production: Life cycle assessment of stepwise catalytic approach","authors":"","doi":"10.1016/j.enconman.2024.118912","DOIUrl":"10.1016/j.enconman.2024.118912","url":null,"abstract":"<div><p>The high-valued utilization of biomass resources remains challenging due to their complex biochemical compositions and limited product selectivity. Herein, we propose a novel biomass stepwise catalytic pyrolysis process to efficiently produce aromatic hydrocarbons and phenols by leveraging the distinct thermal stability of biomass components and their compatibility with ZSM-5 and biochar-based catalysts. A life cycle assessment (LCA) is conducted to evaluate the energy consumption and environmental impact of this innovative process compared to conventional methods. Our findings reveal that this approach significantly reduces the energy consumption by 51.76–90.02 % across different application scenarios of by-product biochar. Additionally, using biochar as a soil amendment contributes to carbon negativity, achieving a net greenhouse gas (GHG) emission reduction of up to 6 t CO₂ eq for producing 8.325 t aromatics and 1 t phenol. The first-stage catalytic pyrolysis for producing aromatic hydrocarbons is identified as the major contributor to environmental impact, mainly due to ZSM-5 catalyst usage and loss, while the second stage for phenol production has a comparatively minor impact. Finally, sensitivity analysis of the key parameters highlights areas for process optimization, including reducing catalyst dosage, minimizing energy consumption, and improving phenol yield, which are crucial for enhancing the environmental and economic viability of the entire route. This study provides a detailed LCA and offers insights for future improvements in biomass conversion technology.</p></div>","PeriodicalId":11664,"journal":{"name":"Energy Conversion and Management","volume":null,"pages":null},"PeriodicalIF":9.9,"publicationDate":"2024-08-14","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141993356","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}

{"title":"A novel BiGRU multi-step wind power forecasting approach based on multi-label integration random forest feature selection and neural network clustering","authors":"","doi":"10.1016/j.enconman.2024.118904","DOIUrl":"10.1016/j.enconman.2024.118904","url":null,"abstract":"<div><p>Accurate wind power forecasting helps to carry out effective scheduling and scientific management of wind power, and improve the security and reliability of the power grid. However, the intermittency, volatility and instability of wind energy make wind power forecasting challenging. Therefore, in order to improve the accuracy and stability of wind power forecasting, this paper proposes a bidirectional gated recurrent unit (BiGRU) multi-step wind power forecasting approach based on multi-label integration random forest (MLRF) feature selection and neural network clustering (NNClustering). The proposed MLRF method extends the applicability of random forest through multiple criteria and enables feature selection for multi-step forecasting tasks of multi-factor time series to obtain optimal input features and time steps, which reduces the computational cost and improves the generalization ability of the model. The proposed NNClustering method establishes a novel convolution-based clustering structure and adjusts the parameters by gradient descent method to obtain the optimal clustering centers, and the robust data applicability of the method is validated in multiple seasonal experiments. The WOA-BiGRU forecasting model is constructed separately for each cluster, which reduces the modeling difficulty and better extracts the characteristics. The BiGRU model extracts more efficient characteristics by processing sequences in both directions and the important parameters of BiGRU are optimized by the whale optimization algorithm (WOA) to obtain the optimal forecasting model. Experimental results over multiple seasons show that the proposed hybrid approach has good forecasting performance and robustness, which provides a novel and efficient solution for wind power forecasting.</p></div>","PeriodicalId":11664,"journal":{"name":"Energy Conversion and Management","volume":null,"pages":null},"PeriodicalIF":9.9,"publicationDate":"2024-08-14","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141993358","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}

{"title":"Hybrid offshore wind–solar energy farms: A novel approach through retrofitting","authors":"","doi":"10.1016/j.enconman.2024.118903","DOIUrl":"10.1016/j.enconman.2024.118903","url":null,"abstract":"<div><p>Due to the inherent variability of the power output of offshore wind farms, their integration into electrical grids poses a challenge to their stability and leads to significant balancing costs. Combining wind and solar power may be expected to mitigate the power output variability. In addition, a number of synergies can be realised—shared infrastructure, shared crews and vessels for operations and maintenance, and last but not least, optimum use of scarce marine space. The objective of this work is to investigate this hybrid approach and, in particular, to determine the optimum capacity of the solar energy subsystem given a certain installed capacity of the wind energy subsystem. Three case studies are considered in Europe and China. Each of them is an existing wind farm that could be retrofitted with floating solar PV. After assessing the local wind and solar energy resources, the optimal size of the floating solar array is calculated with a view to smooth the aggregated power output of each farm. Subsequently, the benefits of this hybrid approach are demonstrated from various perspectives. It is found that a much larger solar array is required for a wind farm with a large installed capacity, but the specific optimal size depends more on the local wind and solar resources. The novelty of this paper lies in its exploration of retrofitting existing offshore wind turbines with floating solar PV systems from the perspective of addressing the variability challenge for the currently operating wind farms. This study could serve as a guideline for project designs aiming to retrofit existing offshore wind farms with solar PV technology, thus reducing balancing costs and facilitating the penetration of offshore renewable energy into national power grids.</p></div>","PeriodicalId":11664,"journal":{"name":"Energy Conversion and Management","volume":null,"pages":null},"PeriodicalIF":9.9,"publicationDate":"2024-08-14","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.sciencedirect.com/science/article/pii/S0196890424008446/pdfft?md5=58b119e0f39732248f4c0487cae0cb65&pid=1-s2.0-S0196890424008446-main.pdf","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141993529","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Optical study of combustion stability in dual fuel approach using ammonia and high reactivity fuel","authors":"","doi":"10.1016/j.enconman.2024.118910","DOIUrl":"10.1016/j.enconman.2024.118910","url":null,"abstract":"<div><p>Ammonia, as a zero-carbon fuel, is considered to be an ideal alternative fuel for a reduction of carbon dioxide emissions. Owing to low laminar flame speed and high ignition energy, the utilization of pure ammonia in powerplant system still presents severe challenges. To solve these issues, the dual fuel combustion of high reactivity fuel and ammonia is a promising solution. However, the dual fuel combustion stability of ammonia and high reactivity fuel has not been clearly understood. In present study, the misfire reasons are investigated using various optical diagnostic methods. Results demonstrate that the misfire reasons are divided into two aspects. One is that the addition of ammonia increases the temperature and pressure required for direction injection fuel auto-ignition, which makes it difficult to generate auto-ignition site, resulting in misfire. The other is that the low flame development speed and degradation of the in-cylinder temperature and pressure causes the difficulty in the further flame development, which results in misfire. A collaborative regulation approach of engine operating condition and direction injection fuel reactivity is proposed to improve combustion stability, which achieves 93% ammonia energy ratio. At 93% ammonia energy ratio, increasing direction injection pressure from 600 bar to 1000 bar decrease combustion stability. The local equivalence ratio of direction injection fuel that can ignite ammonia stably is mainly concentrated between 0.56 and 0.86 in the conditions of 93% ammonia energy ratio and 22 bar in-cylinder pressure. Compared with the in-cylinder temperature, the main factor in determining combustion stability is local equivalence ratio of direction injection fuel. The addition of ammonia prolongs the low temperature reaction and constrains the high temperature reaction of direction injection fuel. In brief, the combustion stability and ammonia energy ratio can be improved simultaneously using the collaborative regulation.</p></div>","PeriodicalId":11664,"journal":{"name":"Energy Conversion and Management","volume":null,"pages":null},"PeriodicalIF":9.9,"publicationDate":"2024-08-14","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141993361","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}