Energy Conversion and Management最新文献

{"title":"Multi-energy load forecasting for small-sample integrated energy systems based on neural network Gaussian process and multi-task learning","authors":"","doi":"10.1016/j.enconman.2024.119027","DOIUrl":"10.1016/j.enconman.2024.119027","url":null,"abstract":"<div><p>Multi-energy load forecasting forms the foundation of the operation and scheduling of integrated energy systems. Nevertheless, insufficient data and underutilization of the coupling relationship between the multi-energy load limit the accuracy of load forecasting. This paper presents a predictive model combining neural network Gaussian processes and multi-task learning. The approach is tailored to enhance forecasting accuracy in environments with small-sample datasets. This model capitalizes on the advantageous properties of infinitely wide neural networks for handling small-sample data. Simultaneously, the model effectively extracts the interconnected dynamics of cooling, heating, and electricity loads within the integrated energy system through multi-task learning. In addition, the model applies concrete dropout, enhancing robustness to irregular loads while maintaining the synergistic benefits of the multi-task framework. Furthermore, this paper employs a two-stage gradient descent approach to replace kernel matrix computations of Gaussian processes, reducing the computational cost of parameter optimization and yielding superior forecasting performance in shorter training durations. The simulation results indicate that the proposed model attains a mean accuracy of 97.93% for a 3-day forecasting horizon. Compared with alternative forecasting models, this model exhibits higher accuracy and enhanced generalization capabilities in multi-energy load forecasting for small-sample integrated energy systems.</p></div>","PeriodicalId":11664,"journal":{"name":"Energy Conversion and Management","volume":null,"pages":null},"PeriodicalIF":9.9,"publicationDate":"2024-09-14","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142232118","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":"Experimental study of novel desiccant coated energy exchanger employing PCM – Silica gel working pair for air conditioning and thermal energy storage application","authors":"","doi":"10.1016/j.enconman.2024.119042","DOIUrl":"10.1016/j.enconman.2024.119042","url":null,"abstract":"<div><p>Advancement of air conditioning systems is a key focus because of high energy usage and rising demand for better air quality. Desiccant air conditioning offers enhanced energy management and sustainability features. Phase change material (PCM) based thermal energy storage systems are effective for efficient thermal energy storage applications. Hence, the practicality of integrating PCM with desiccant coated energy exchangers (DCEE) for air conditioning and thermal energy storage necessitates experimental investigation. Therefore, a novel desiccant coated circular fin tube energy exchanger (DCCEE) has been designed and fabricated in this study. DCCEE is integrated with PCM to assess its dehumidification and thermal energy storage characteristics. The key highlight of this work is the use of PCM-silica gel as the working pair instead of conventional water–silica gel. A linear driving force model is used to evaluate the silica gel’s adsorption and desorption kinetics. Experiments have been designed by response surface methodology employing the central composite design technique to analyze the effect of independent parameters on the response of DCCEE. The variation in the cooling capacity, adsorption effectiveness, and PCM temperature at different input conditions has been judiciously evaluated. The adsorption capacity of silica gel is 0.332 g/g at a relative pressure of 0.9. Under the air velocity of 2.5 m/s, the total cooling capacity of DCCEE has the highest value of 3.55 kW, which consists of 1.18 kW sensible cooling capacity and 2.37 kW latent cooling capacity. At the 20 °C and 22 g_wv/kg_da condition, the adsorption effectiveness reaches a maximum value of 0.82. During adsorption, PCM melts in response to different input parameters and reaches phase change point in 490 s (air temperature), 540 s (air velocity), and 570 s (relative humidity), respectively. To conclude, this study elucidates the feasibility of integrating PCM with DCEE and provides a reference for DCEE system design.</p></div>","PeriodicalId":11664,"journal":{"name":"Energy Conversion and Management","volume":null,"pages":null},"PeriodicalIF":9.9,"publicationDate":"2024-09-14","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142232117","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":"Synthetic natural gas as a green hydrogen carrier – Technical, economic and environmental assessment of several supply chain concepts","authors":"","doi":"10.1016/j.enconman.2024.118940","DOIUrl":"10.1016/j.enconman.2024.118940","url":null,"abstract":"<div><p>Based on synthetic natural gas, existing natural gas markets and infrastructures can be used to make renewable sources of energy from sun- and/or wind-rich regions available on a global scale. To overcome the challenge of providing non-fossil CO₂ for the production of this synthetic natural gas, a novel concept analyzed in this paper envisages to reform the synthetic natural gas in the importing country and transporting the captured CO₂ back to the exporting country to be reused for the production of synthetic natural gas; i.e., the synthetic natural gas serves as a hydrogen carrier. This paper examines and compares the energy efficiency, cost and greenhouse gas emissions of different hydrogen supply chains using synthetic natural gas as a carrier related to the year 2030. To do so, all relevant components are taken into account to model the entire supply chains. A special focus is put on different options for providing the required CO₂ and on different technologies for synthetic natural gas reforming. The assessment shows that the availability of a cheap source of biogenic CO₂ at the point-of-export as well as electrified steam methane reforming result in the lowest hydrogen supply cost of 6.6 to 7.0<!--> <!-->€₂₀₂₀/kg_H2, also achieving best results in terms of energy efficiency (around 44%). With regard to minimizing greenhouse gas emissions, autothermal reforming of methane appears to be advantageous. A closed CO₂ cycle is favorable over sole onsite CO₂ provision, if no cheap CO₂ of non-fossil origin is available at the point-of-export and the costly direct air capture process would have to be used.</p></div>","PeriodicalId":11664,"journal":{"name":"Energy Conversion and Management","volume":null,"pages":null},"PeriodicalIF":9.9,"publicationDate":"2024-09-13","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.sciencedirect.com/science/article/pii/S0196890424008811/pdfft?md5=18d04ab260518db1e73b9515acef80f5&pid=1-s2.0-S0196890424008811-main.pdf","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142229480","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":"Process design and techno-economic analysis of the coproduction of oil, electricity, and protein from plastics and biomass using an integrated system","authors":"","doi":"10.1016/j.enconman.2024.119040","DOIUrl":"10.1016/j.enconman.2024.119040","url":null,"abstract":"<div><p>To synergistically exploit plastic and biomass, a hybrid system combining pyrolysis and gasification has been proposed, which has been dedicated towards the conversion of non-recycled plastic and biomass to the coproduction of oil, electricity, and protein. Non-recycled plastic is transformed into high-value pyrolysis oil, char, and gas through pyrolysis. Simultaneously, biomass undergoes gasification to produce high-quality syngas. Part of this syngas is utilized in a gas-steam combined cycle to produce electricity, while another portion is mixed with pyrolysis gas to produce protein. This innovative hybrid system reduces greenhouse gas emissions and environmental pollution compared to traditional methods. Additionally, the diversification of energy outputs enhances the system’s overall efficiency and its ability to meet varying energy demands. The proposed system achieves a total energy efficiency of 55.33 % and an exergy efficiency of 52.83 %. Furthermore, it boasts a short dynamic payback period of 3.36 years and a high net present value of 144,603.61 k$.</p></div>","PeriodicalId":11664,"journal":{"name":"Energy Conversion and Management","volume":null,"pages":null},"PeriodicalIF":9.9,"publicationDate":"2024-09-13","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142229479","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":"Experimental investigation and thermo-electrical performance modeling of two PV plants in arid climates","authors":"","doi":"10.1016/j.enconman.2024.119025","DOIUrl":"10.1016/j.enconman.2024.119025","url":null,"abstract":"<div><p>In the target of 100% renewable energy by 2050, photovoltaic (PV) performance modeling is important for accurately predicting the electricity generation profile. This study aims to develop a new model based on 1) tilted irradiance, 2) ambient and module temperatures, and 3) output power. Thus, this method enables more accurate use of tilted irradiance and ambient temperature with investigated thermo-electrical parameters in the sc-Si PV efficiency modeling under arid climates. Therefore, we focus on the comparison of the measured cell temperature and output inverter power with ten/eight relevant thermo-electrical models, including the proposed one.</p><p>Three empirical input parameters are investigated based on experimental data collected from two R&amp;D PV plants in Morocco. The operating Temperature Coefficient of Power, Low Light Efficiency, and heat loss U_L for the investigated PV modules in Marrakech are −0.4541 %/°C, 94 %, and 47 W/m²/°C, respectively. Due to the low wind effect, U_L is 10 % lower than Essaouira’s value. All empirical parameters investigated are very close to the estimated values using some models from the literature, while they are not equal to the values provided by the manufacturers. The NRMSE is reduced by about 2 times after data cleaning for all electrical models. Consequently, the proposed model is the best, with a minimal NRMSE of 4.34 % and a maximal R² and Quality-Accuracy Index of 99.67 % and 19.83, respectively, which demonstrates why the inclusion of the second-order logarithmic irradiance effect plays an important role in PV efficiency modeling. Additionally, non-linear models perform better than multi-linear ones, with an RMSE and MBE less than 25 and 6 W/kW_p, respectively. The proposed method is designed to support researchers and engineers in accurately predicting PV power under various operating and environmental conditions.</p></div>","PeriodicalId":11664,"journal":{"name":"Energy Conversion and Management","volume":null,"pages":null},"PeriodicalIF":9.9,"publicationDate":"2024-09-12","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142169287","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":"Unveiling the potential of solar cooling technologies for sustainable energy and environmental solutions","authors":"","doi":"10.1016/j.enconman.2024.119034","DOIUrl":"10.1016/j.enconman.2024.119034","url":null,"abstract":"&lt;div&gt;&lt;p&gt;The escalating growth in the traditional air-conditioning industry has led to an increased demand for energy. However, this industry has the drawbacks of high energy consumption and is non-environmentally friendly. Solar cooling technologies emerge as a pivotal solution to overcome these challenges, presenting an ideal alternative for energy and environmental considerations. However, the main drawbacks of solar cooling technologies are their initial high cost and comparatively lower performance, which remain obstacles to their broader implementation. Despite recent advancements, these technologies still struggle to compete with traditional cooling methods due to cost, performance, and maintenance challenges. This review focuses on categorizing solar cooling systems and provides a detailed examination of each type, with a specific emphasis on the most significant ones. Additionally, this work includes a historical overview of the utilization of solar energy in various cooling and refrigeration processes, covering aspects of design and application. Specifically, the article provides an extensive review of various solar-powered cooling techniques, including photovoltaic, photovoltaic-thermal (PVT), absorption, desorption, and mechanical systems, and their potential to enhance energy efficiency. It also covers the contributions of optimization and machine learning in improving the efficiency of solar cooling technologies. The current study conducts a broad survey of diverse cooling systems utilizing solar energy for either full or partial operation. Recent studies encourage for multi-functional hybrid solar cooling technologies that offer innovative solutions with low energy consumption, high performance, and cost-effectiveness. These systems are well-suited for both industrial and domestic applications. The findings of this study align with previous research, affirming that solar absorption systems are the most prevalent among various solar cooling systems. The efficacy of solar cooling is contingent on several factors, with paramount importance placed on weather conditions, sunlight intensity, and the size of the space intended for cooling. The optimal utilization of solar energy collectors and advancements in flat plate technologies have significantly improved the performance of closed adsorption and absorption cooling systems, as well as enhanced the effectiveness of their components. Additionally, the study concluded that solar cooling systems are integrated solutions, commencing with a thoughtful selection of either photovoltaic panels or solar collectors, followed by energy conservation storage, and concluding with a suitably matched cooling unit. Finally, the review emphasizes the need for continued research and development in solar cooling technologies, with a focus on optimizing performance, enhancing efficiency, and expanding their application in various settings. Future studies should focus on enhancing the coefficient of performa","PeriodicalId":11664,"journal":{"name":"Energy Conversion and Management","volume":null,"pages":null},"PeriodicalIF":9.9,"publicationDate":"2024-09-12","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142173253","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":"Unveiling the potential of pyrolysis-gasification for hydrogen-rich syngas production from biomass and plastic waste","authors":"","doi":"10.1016/j.enconman.2024.118997","DOIUrl":"10.1016/j.enconman.2024.118997","url":null,"abstract":"<div><p>The paper highlights the emerging importance of hydrogen as a clean and sustainable energy with a focus on biomass and plastic waste feedstocks. The effectiveness of different gasification operations, including co-gasification, pyrolysis-gasification, and co-pyrolysis-gasification in producing hydrogen-rich syngas from biomass and plastic wastes, has been explored. The paper also probes the catalytic characteristics of the process, examining the functions of various metal catalysts, including alkaline earth metallic catalysts, and natural mineral catalysts for enhancing the hydrogen-rich syngas generation. Further, the effect of key operating factors including the synergy in co-gasification reactors, the influence of gasifying agents, temperatures, pretreatment effects, and types of gasification reactors on hydrogen yield and quality were extensively examined. The pyrolysis-gasification of biomass and plastic waste not only solves waste management issues but also creates new opportunities to produce clean energy, which is a major step towards a circular economy. Biomass and plastic waste feedstocks, various types of gasification techniques and their reactions and mechanisms, the effects of catalysts, as well as the effects of other parameters influence the overall hydrogen production during pyrolysis-gasification. The review offered a novel approach to improving the sustainability and efficiency of hydrogen production from waste by incorporating recent advances in reactor design and process optimization. It also identifies future research directions and practical applications.</p></div>","PeriodicalId":11664,"journal":{"name":"Energy Conversion and Management","volume":null,"pages":null},"PeriodicalIF":9.9,"publicationDate":"2024-09-12","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142173254","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":"An innovative approach to assessing and optimizing floating solar panels","authors":"","doi":"10.1016/j.enconman.2024.119028","DOIUrl":"10.1016/j.enconman.2024.119028","url":null,"abstract":"<div><p>Floating photovoltaic energy is an emerging solution to the need for decarbonization of the current society. It is currently in the early stages of implementation, so there are not many previous experiences to standardize decision-making and the most relevant operating parameters such as, the tilt angle of a fast as in conventional photovoltaics. In addition, the lack of specific design tools and production calculations for floating solar is a barrier to the correct understanding of the real advantages of floating solar versus conventional solar. From the point of view of the investment, the stakeholders do not have a complete analysis of the profitability of their investment. From a technical, environmental and legislative point of view, there is not enough information available to establish standards and criteria for the design and selection of the most suitable water bodies at local, regional or state level. This research aims to fill this gap by proposing a specific framework based on geographic information systems (GIS), multi-criteria analysis (MCDA) and intelligent optimization (Genetic Algorithm). The objective is to select within a set of water bodies those where the investment is most beneficial from a holistic perspective considering technical, economic, social, environmental, and legislative criteria. Once the optimal location is obtained, the framework obtains the tilt angles that minimize the Levelized Cost of Energy (LCOE) by means of intelligent optimization techniques that evaluate the characteristics of each water body, such as location or available surface. The tilt angle obtained in this research achieves LCOE improvements of between 2.1% and 8.4% with respect to the tilt angle obtained by conventional methods applied to ground photovoltaics. Spain has been chosen as a case study as it is a region with a high solar potential and an even distribution of water bodies in which there is still no legislative framework in force.</p></div>","PeriodicalId":11664,"journal":{"name":"Energy Conversion and Management","volume":null,"pages":null},"PeriodicalIF":9.9,"publicationDate":"2024-09-11","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.sciencedirect.com/science/article/pii/S0196890424009695/pdfft?md5=9d0b8acdbc2f7f7932713f6c489c144f&pid=1-s2.0-S0196890424009695-main.pdf","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142169288","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":"A comprehensive review of hexanol and its blends in diesel engines","authors":"","doi":"10.1016/j.enconman.2024.119004","DOIUrl":"10.1016/j.enconman.2024.119004","url":null,"abstract":"<div><p>Growing concerns regarding global warming, climate change, air pollutants and rising energy demand, have triggered many researchers to explore better, alternate renewable energy resources. Hexanol, a next generation fuel, which can be derived from renewable resources, has emerged as a promising candidate due to its higher energy density, greater calorific value, higher cetane number, lower latent heat of evaporation, lower hygroscopic, and lower corrosiveness when compared to the light alcohols such as methanol, and ethanol. Furthermore, it has higher flash point, and low volatility, making it safe for storage and transportation. This study provides an in-depth analysis of research on hexanol usage in diesel engines. First, the feedstocks, production methods, environmental and human health impacts, supply and demand, and the fuel application of hexanol are reported. Subsequently, different hexanol variations including single, binary blends (hexanol-biodiesel and hexanol-diesel), ternary blends (hexanol, biodiesel and petroleum diesel) and multi-blends applications are separately reviewed and compared to petrol diesel. Hence, this study clearly demonstrates the effects of hexanol on the combustion parameters, performance, and exhaust emissions of diesel engines. Consequently, it highlights general conclusions and future proposed research directions. The utilization of hexanol as a drop-in fuel has been thoroughly summarized to guide and inform future research efforts.</p></div>","PeriodicalId":11664,"journal":{"name":"Energy Conversion and Management","volume":null,"pages":null},"PeriodicalIF":9.9,"publicationDate":"2024-09-11","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142163826","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":"Low-emissions hydrogen from MCH dehydrogenation: Integration with LNG regasification","authors":"","doi":"10.1016/j.enconman.2024.119012","DOIUrl":"10.1016/j.enconman.2024.119012","url":null,"abstract":"<div><p>Methylcyclohexane (MCH) is a promising organic hydride carrier for hydrogen transport and storage. Recovering hydrogen from MCH is an energy intensive process. An innovative idea of integrating this process with liquified natural gas (LNG) regasification is proposed in this study and demonstrated via modelling and simulation to substantially reduce external energy use. The synergistic benefits are twofold. In addition to providing a cold energy source for an effective high recovery cryogenic flash separation, the organic Rankine cycle based electrical power generation potential from LNG cold energy is fully exploited to reduce/eliminate external electricity demand for hydrogen compression to the high (end use) pressure. The results is a major reduction in carbon dioxide emissions. The proposed design for an integrated LNG-H₂ <!-->terminal can supply (1) 99.99 mol% pure hydrogen to a Combined Cycle Gas Turbine (CCGT) power plant and (2) commercial-grade natural gas to a gas-grid, both at the desired pressures and temperatures. Subsequently, rigorous simulation-based optimization was performed to minimize external energy inputs.<!--> <!-->A case study with 100 tph MCH and 100 tph LNG showed that integrating regasification with dehydrogenation produced 6.2 tph of hydrogen while gasifying LNG with a net power generation of 310 kW and a hydrogen recovery cost of 0.282 $/kg H₂. Up to 7.3 tonnes of hydrogen can be produced per 100 tonnes of LNG without the use of external power. On the other hand, using external power, up to 11.3 tonnes of hydrogen can be produced per 100 tonnes of LNG without any external refrigeration. Overall, the superstructure proposed in this manuscript provides a generic initial approach for future MCH hydrogen supply chain projects, when considering integrations with LNG regasification plants.</p></div>","PeriodicalId":11664,"journal":{"name":"Energy Conversion and Management","volume":null,"pages":null},"PeriodicalIF":9.9,"publicationDate":"2024-09-11","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142169202","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}