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Carbon capture and utilization (CCU) is a field of key emerging technologies. CCU can support the economy to decrease the dependency on fossil carbon raw materials, to stabilize electricity grids and markets with respect to a growing share of fluctuating renewable energy. Furthermore, it can contribute to mitigate anthropogenic CO2 emissions. The German Federal Ministry of Education and Research has provided substantial financial support for research and development projects, stimulating research, development, and innovations in the field of CO2 utilization. This review provides an overview over the most relevant funding measures in this field. Examples of successful projects demonstrate that CCU technologies are already economically viable or technologically ready for industrial application. CCU technologies as elements of a future "green economy" can contribute to reach the ambitious German sustainability targets with regard to climate protection as well as raw material productivity.

Efficiency of energy resource use is a key factor for a sustainable energy future. By matching the exergy levels of supply and demand, Energy Quality Management (EQM) of building energy supply systems may achieve more efficient use of energy resources. Beyond this, environmental impact of energy supply systems is another essential issue. This work addresses the influence of EQM on CO 2 emissions in the operation optimization of a Distributed Energy System (DES). A multi-objective linear programming problem is formulated to reduce energy costs and increase the overall exergy efficiency. Total CO 2 emissions are evaluated for the optimized operation strategies of the DES. The operators of the DES can choose the operation strategy from the Pareto front, based on their priorities and also aware of effects on CO 2 emissions. Results demonstrate more efficient use of energy resources and reduction in CO 2 emissions through EQM, as compared with conventional energy supply systems.

Biomass is a promising alternative energy source for fossil fuel with the advantages of abundance, renewability, environmental friendliness, etc. This makes the development of biomass technology be of great potential and interesting. The experiments of biomass fast pyrolysis were performed in a microquartz reactor for rice husk (RH), corn stalk (CS) and birch wood (BW), and scanning electron microscope (SEM), energy dispersive spectrometer, and Raman microscope were then applied to analyze the collected chars. The average char yields of RH, CS, and BW pyrolyzed at 800 °C were 29.64%, 18.67%, and 8.64%, respectively. The morphological structures of RH and CS were mainly reserved in chars, while the raw surface textures of BW disappeared during the fast pyrolysis. The silicon concentrations in RH char and CS char were much higher than BW char, and the graphitization degree of CS char was the lowest among the three biomass chars.

Abstract Dynamic modeling of HVAC system is extremely important for control analysis toward building energy saving. In order to provide researchers a simulation platform to analyze different control strategies, this paper introduces a simulation platform with customized Simulink block library based on dynamic HVAC component model. As an initiating effort, the current simulation platform is composed of basic modular HVAC components, including conduit, damper/valve, fan/pump, flow merge, flow split, heating coil, cooling coil, and zone. These modules are developed into Simulink customized blocks. The simulation platform is capable to calculate the flow rates of fresh air, exhaust air, and return air based on system characteristic and fan curve with customizable basic/advanced control strategies. A case study is proposed using single-zone, constant volume system by comparing the uncontrolled, fixed temperature and damper position controlled, and schedule based reset controlled cases. The simulation result proves that schedule based temperature and damper position reset has a significant impact on energy saving for both heating and cooling seasons. This simulation platform can be especially useful for analyzing the dynamic performance of different HVAC control strategies.

Abstract In this paper, we investigate distributed thermal-electrochemical modeling of a Lithium-Ion battery cell to include the effect of temperature distribution across the thickness of the cell as a first step to study the module level temperature distribution at high charging rates. Most recent works have focused on lumped thermal models for a Li-Ion cell which ignore any temperature differential across cell thickness. However, even a small temperature differential across cell thickness at the cell level can contribute to significant temperature differential in the thickness direction of stacked-up Li-Ion cells at the module level. Such temperature differential can potentially impact the battery charging control system, especially at high charging rates. Here, the thermal-electrochemical partial differential and algebraic equations for a Li-ion cell are solved via a spatial finite difference method. Simulation results show that the temperature differentials over the cell thickness at the cell level are not insignificant, particularly at high charging rates.

Heat transfer between a hot, semi-infinite plate and thin liquid film flowing over its surface is considered. As the plate is semi-infinite, the finite cooled portion of the plate and the temperature at the moving film front are time variable. The heat transfer is transient, as opposed to the usual quasi-steady process that exists when the plate is infinite. To investigate the transient heat transfer, solutions describing the temperature fields of the wet and dry portions of the plate are conjugated at the moving film front. The basic characteristics of transient cooling process are found to be governed by a dimensionless parameter named the Leidenfrost number, which is the ratio of the Biot number and the square of the Peclet number. The plate temperatures at the moving front, the film velocity, and the time required to reach the wetting temperature are calculated.

Abstract Global warming is a major challenge that we are facing today that involves the emission of harmful greenhouse gases like carbon dioxide (CO 2 ) into the atmosphere. Pressurized pipelines are considered to be the most efficient and reliable way to transport CO 2 due to the high density and low viscosity of CO 2 . Any accidental discharge from such high pressure pipelines may result in significant damage to the ambient atmosphere and a powerful threat to human health. The unusual phase transition behavior of CO 2 post leak can pose challenging risks for modeling the safe transportation of CO 2 , which is one of the most critical process design considerations in a carbon capture and storage (CCS) area. The current consequence model described in this work predicts the transient jet release rates and the concentration variations of pure CO 2 over a given period of time and distance in Fluent 16.2. This has been validated against experimental work carried out by BP’s DF1 project at the Spadeadam site. The work has been extended to study the effect of terrain on the final downwind concentration of CO 2 . This consequence model could successfully predict the minimum safe distances to populated areas and can be used as a risk assessment tool for planning emergency response in case of pipeline leakage during CO 2 transport.

Los nodos de red de sensores inalámbricos tienen una energía limitada, la forma de emplear la energía limitada de manera eficiente para realizar una transmisión de datos efectiva se ha convertido en un tema candente. Teniendo en cuenta las características de la plantación de huertos en filas y sombras causadas por características aleatorias dispersas, para mejorar la eficiencia energética de la red de sensores inalámbricos de huertos y prolongar la vida útil de la red, proponemos un algoritmo mejorado de enrutamiento jerárquico de agrupamiento basado en cadenas (ICCHR) basado en el algoritmo de LIXIVIACIÓN. El algoritmo ICCHR investiga la formación de grupos, la elección de la cabeza del grupo, la formación de la cadena, así como el proceso de transmisión de datos, y además se simula con los algoritmos E-LEACH, PEGASIS-E, LEACH-1R PEGASIS y P-LEACH a través de MATLAB. Los resultados de la simulación muestran que para BS en (50, 175), desde el punto de vista de la métrica de muerte de todos los nodos sensores, la vida útil de la red para el algoritmo ICCHR se prolonga aproximadamente 3.29, 8.78, 35.53 y 43.11% en comparación con los algoritmos E-LEACH, PEGASIS-E, LEACH-1R PEGASIS y P-LEACH. El consumo medio de energía por ronda del algoritmo ICCHR es inferior a los algoritmos E-LEACH, PEGASIS-E, LEACH-1R PEGASIS y P-LEACH en aproximadamente 4,73, 9,04, 35,60 y 43,31%. Esta investigación puede proporcionar referencias teóricas para las redes inalámbricas del entorno complejo del huerto. Les nœuds de réseau de capteurs sans fil ont une énergie limitée, comment utiliser efficacement une énergie limitée pour réaliser une transmission de données efficace est devenu un sujet brûlant. Compte tenu des caractéristiques de la plantation de vergers en rangées et à l'ombre causées par des caractéristiques aléatoires clairsemées, afin d'améliorer l'efficacité énergétique du réseau de capteurs sans fil du verger et de prolonger la durée de vie du réseau, nous proposons un algorithme amélioré de routage hiérarchique en grappe basé sur la chaîne (ICCHR) basé sur l'algorithme de LIXIVIATION. L'algorithme ICCHR étudie la formation de grappes, l'élection de la tête de grappe, la formation de la chaîne ainsi que le processus de transmission de données, et est ensuite simulé avec les algorithmes E-LEACH, PEGASIS-E, LEACH-1R PEGASIS et P-LEACH via Matlab. Les résultats de simulation montrent que pour BS à (50, 175), du point de vue de toutes les métriques de mort des nœuds du capteur, la durée de vie du réseau pour l'algorithme ICCHR prolonge d'environ 3,29, 8,78, 35,53 et 43,11% par rapport aux algorithmes E-LEACH, PEGASIS-E, LEACH-1R PEGASIS et P-LEACH. La consommation d'énergie moyenne par tour de l'algorithme ICCHR est inférieure à celle des algorithmes E-LEACH, PEGASIS-E, LEACH-1R PEGASIS et P-LEACH d'environ 4,73, 9,04, 35,60 et 43,31 %. Cette recherche peut fournir des références théoriques pour le réseau sans fil de l'environnement complexe du verger. Wireless sensor network nodes have limited energy, how to employ limited energy efficiently to realize effective data transmission has become a hot topic. Considering the characteristics of orchard planting in rows and shade caused by sparse random features, to improve energy efficiency of the orchard wireless sensor network and prolong network lifetime, we propose an improved chain-based clustering hierarchical routing (ICCHR) algorithm based on LEACH algorithm. The ICCHR algorithm investigates the formation of clusters, cluster head election, chain formation as well as the data transmission process, and further simulated with E-LEACH, PEGASIS-E, LEACH-1R PEGASIS and P-LEACH algorithms through MATLAB. The simulation results show that for BS at (50, 175), from the point of view of all sensor nodes death metric, the network lifetime for ICCHR algorithm prolongs about 3.29, 8.78, 35.53, and 43.11% compared with E-LEACH, PEGASIS-E, LEACH-1R PEGASIS and P-LEACH algorithms. The average energy consumption per round of the ICCHR algorithm is lower than E-LEACH, PEGASIS-E, LEACH-1R PEGASIS and P-LEACH algorithms about 4.73, 9.04, 35.60, and 43.31%. This research can provide theoretical references for the orchard complex environment wireless networking. تتمتع عقد شبكة المستشعرات اللاسلكية بطاقة محدودة، وأصبحت كيفية استخدام الطاقة المحدودة بكفاءة لتحقيق نقل البيانات الفعال موضوعًا ساخنًا. بالنظر إلى خصائص زراعة البساتين في الصفوف والظل الناجم عن الميزات العشوائية المتفرقة، لتحسين كفاءة استخدام الطاقة لشبكة استشعار البساتين اللاسلكية وإطالة عمر الشبكة، نقترح خوارزمية محسنة للتوجيه الهرمي للتجميع القائم على السلسلة (ICCHR) بناءً على خوارزمية الرشح. تبحث خوارزمية المركز الدولي لحقوق الإنسان في تشكيل المجموعات واختيار رؤساء المجموعات وتشكيل السلسلة بالإضافة إلى عملية نقل البيانات، وتمت محاكاتها بشكل أكبر باستخدام خوارزميات E - LEACH و PEGASIS - E و LEACH -1R PEGASIS و P - LEACH من خلال MATLAB. تظهر نتائج المحاكاة أنه بالنسبة لـ BS عند (50، 175)، من وجهة نظر جميع مقاييس موت عقد المستشعرات، فإن عمر الشبكة لخوارزمية ICCHR يمتد إلى حوالي 3.29 و 8.78 و 35.53 و 43.11 ٪ مقارنة بخوارزميات E - LEACH و PEGASIS - E و LEACH -1R PEGASIS و P - LEACH. متوسط استهلاك الطاقة لكل جولة من خوارزميات المركز الدولي لحقوق الإنسان أقل من خوارزميات E - LEACH و PEGASIS - E و LEACH -1R PEGASIS و P - LEACH حوالي 4.73 و 9.04 و 35.60 و 43.31 ٪. يمكن أن يوفر هذا البحث مراجع نظرية لبيئة البستان المعقدة للشبكات اللاسلكية.

Abstract System-level dynamic models of power plants are valuable tools for the assessment and prediction of plant performance, decisions on the design configuration, and the tuning of operating procedures and control strategies. In this work, the development of an integrated power plant model is presented. This model is validated against steady-state data from a subcritical power plant with reheat and regenerative cycles. The coal-fired power plant model studied has nominal power generation of 605 MW and efficiency of 38.3%. Traditional, regulatory control architectures are incorporated into and tuned with the dynamic power plant model. Dynamic simulation shows that the plant model is stable for sudden changes in coal load, and the controllers are able to maintain the controlled variables at their set points. In this two-part publication, we present the complete workflow of data collection, model development and validation, control tuning, dynamic optimization formulation and solution, and supervisory control architecture for a coal-fired subcritical power plant. Part I focuses on elements of model development and analysis, illustrating the advantages of acausal, object-oriented modeling in power plant simulation. Part II illustrates the use of this model for efficiency optimization under transient part-load operation.