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[en] Highlights: • The surface structure, including morphological transformations was investigated. • Combined experimental and calculations results to develop a Wulff construction model. • Study of the correlation between crystal shape modulation and surface energy. In this communication, a systematic study of the surface structure, including energy management during morphological transformations of tetragonal phase of LaVO4, has been carried out. For this study, we combined experimental findings and first-principles calculations to develop a Wulff construction model. Our findings can help further understand the synthetic control of crystal shape via tuning of surface chemistry.
[en] The nexus among real income, energy consumption, financial development, and carbon emission has broadly conferred area in energy and environmental literature. However, there is no study in the literature which investigates the moderating role of financial development between real income, energy consumption, and CO2 emission in Pakistan. This study reveals the role of financial development as a moderator in the conventional environmental Kuznets curve (EKC). To achieve the objectives of this study, two approaches are employed, (i) with main effects and (ii) with interaction variables, using autoregressive distributed lag (ARDL) bounds testing approach in the case of Pakistan covering the period 1970 to 2016. Findings of the empirical analysis confirm the EKC hypothesis in the first case (without interaction effect) and our second estimations (with interaction effect) show that financial development significantly moderates the association of real output with CO2 emission (both for the long run and short run). The negative effect of financial development on carbon emission reveals to efficacious energy management with effective environmental performance. More precisely, the results of second estimations reveal that all three interaction variables are statistically significant but the EKC curve is no more. Thus, the current study proposes that the moderating effect of the financial sectors may be the possible reason which has been ignored by prior researchers and they found mix results regarding the existence of EKC in Pakistan. In addition, the Granger causality test confirms the feedback effect between real income and carbon emission and one-way causality from all the three interaction variables and financial development to CO2 emission. Lastly, this study posits some important policy inferences in the perspective of new economic policy formation in Pakistan.
[en] Role of SMRs in Climate Change - SMR Renewables Hybrid Energy System to Reduce GHG Emission: ‣ Hybrid Energy System (HES) utilizes two or more energy resources as inputs to two or more physically coupled subsystems to produce one or more energy commodities as outputs; ‣ HES integrate energy conversion processes to optimize energy management, reliability, security, and sustainability. ‣ The “SMR RES HES” facilitate effective integration of renewable energy, overcoming the challenges of intermittency and transmission constraints.
[en] Lithium-ion batteries are widely used in many applications due to their high energy and power density. However, an important factor here is also the lifetime. During operation there is a loss of capacity as well as an increase of internal resistance. The aim of this work is the identification and quantification of the degradation processes under calendar and cyclical aging and the effect of the electrode microstructure on the ageing behaviour.
[de]Lithium-Ionen Batterien sind aufgrund ihrer hohen Energie- und Leistungsdichte in vielen Anwendungen weit verbreitet. Ein wichtiger Faktor ist hierbei aber auch die Lebensdauer. So kommt es während des Betriebs sowohl zu einem Kapazitätsverlust, als auch zu einem Anstieg des Innenwiderstandes. Ziel der Arbeit ist die Identifikation und Quantifizierung der Degradationsanteile bei kalendarischer und zyklischer Belastung und die Auswirkung der Elektrodenmikrostruktur auf das Alterungsverhalten.
[en] With the aim of reducing greenhouse gas emissions, technologies are increasingly being electrified. Examples include electric cars and heat pumps. However, fluctuating power generation from wind and sun and the irregular operation of combustion power plants already lead to environmental profiles of the power supply that vary over time. For electricity consuming products, it is therefore highly relevant when and with which mix the electricity is generated. The HD-LCA method (Hourly Defined Life Cycle Assessment) makes it possible to determine environmental profiles of the current and future power supply in hourly resolution. The electricity and heat generation of individual power plants, start-up and shut-down processes and varying efficiencies and emissions at partial load are taken into account. The application of the method to the example of the German electricity supply in 2014 shows that the hourly resolution of the greenhouse potential and other environmental impacts entails significant deviations compared to annual mean values. The HD-LCA method contributes to the ecological design of the power supply and the development of ecological products through the realistic life cycle assessment.
[de]Mit dem Ziel der Senkung des Treibhausgasausstoßes werden Technologien zunehmend elektrifiziert. Beispiele hierfür sind Elektroautos und Wärmepumpen. Die fluktuierende Stromerzeugung aus Wind und Sonne und der unregelmäßige Betrieb von Verbrennungskraftwerken führen jedoch schon heute zu zeitlich variierenden Umweltprofilen der Stromversorgung. Für stromverbrauchende Produkte ist es daher hochrelevant, wann und mit welchem Mix der Strom erzeugt wird. Die HD-LCA-Methode (Hourly Defined Life Cycle Assessment) ermöglicht es, Umweltprofile der heutigen und zukünftigen Stromversorgung in stündlicher Auflösung zu ermitteln. Es werden die Strom- und Wärmeerzeugung einzelner Kraftwerke, An- und Abfahrvorgänge und in Teillast variierende Wirkungsgrade und Emissionen berücksichtigt. Die Methodenanwendung am Beispiel der deutschen Stromversorgung 2014 zeigt, dass die stündliche Auflösung des Treibhauspotentials und weiterer Umweltwirkungen signifikante Abweichungen im Vergleich zu jährlichen Mittelwerten mit sich bringt. Die HD-LCA-Methode leistet durch die realitätsnahe Ökobilanzierung einen Beitrag zur ökologischen Gestaltung der Stromversorgung und zur Entwicklung ökologischer Produkte.
[en] The transition to digital technology has changed the nature of instrumentation and control (l&C) systems by enabling extensive interconnection of reprogrammable, functionally interdependent I&C systems. This development has made computer security a necessary element for consideration in I&C system design. The benefits and challenges of the various computer security methods and controls with their implementation in nuclear power plant I&C systems are discussed and described in this publication. The publication provides an overview of current knowledge, up to date good practices, experience, and benefits and challenges related to the application of computer security measures. The publication defines the key concepts for computer security for I&C systems at nuclear facilities, explains the risk informed approach to computer security and describes how computer security measures are applied throughout the l&C system life cycle. Situations where I&C systems are interconnected with enterprise management systems are also addressed. The three appendices present case studies with practical application examples.
[en] The Hanford site, located in southeastern Washington, produced much of our nation's weapons-grade plutonium for the Defense nuclear weapons program. This production lasted the better part of four decades with production ending in 1987. Since 1987, the focus of the Hanford site has turned to clean-up activities. Mission Support Alliance (MSA) is the integrator of the multi-contractor effort to clean up the Hanford site. MSA collaborates with the U.S. Department of Energy (DOE) and all Hanford site contractors in finding and implementing new, cost-saving, safe and practical solutions to cleanup challenges with a continual focus on innovative processes and technologies that reduce costs, energy use and bring safety improvements to the site. Support Services include environmental integration and land management; fleet and road maintenance; water/electric and utilities; cyber security and information management as well as the preservation of the site's cultural artifacts. This paper describes the process, challenges, and focus on infrastructure upgrade and energy efficiency projects in the context of a multi-contractor nuclear clean-up site. Project development and new technology deployment at Hanford has long been plagued with economic challenges. For example, despite extensive auditing, analysis, and project development, most of the energy-related projects on the Hanford site have gone unfunded due to the low cost of electricity, the relatively high cost of labor, and costs associated with detailed safety and cultural reviews. - The Hanford site is a direct-service customer of the Bonneville Power Administration (BPA) and has a marginal electricity rate of $0.033/kWh. - Labor costs on the Hanford site track high because of the requirements associated with the safety and security necessary to operate a legacy nuclear weapons complex. - In partnership with three federally recognized and other affected Native American tribes (Yakama Nation, Confederated Tribes of the Umatilla Indian Reservation, the Nez Perce Tribe, and Wanapum People), most activities on the Hanford site are afforded in-depth cultural reviews. To work within these constraints, the MSA Energy Management team has embarked on a three-pronged approach to energy project development: Program Visibility: The MSA Energy Management team has promoted both project opportunities and requirements across the Hanford site. This information comes in the form of site-wide newsletters, group meetings, e-mails, success stories, and recognition of staff. Single-point Analysis: To by-pass the inevitable duplications of effort, learning curve issues, and to improve project consistency/delivery, the MSA Energy Management team serves as the single resource to the site for energy project analysis. This resource includes initial assessment, engineering analysis, efficiency calculation and project recommendations. Contractor/utility Interface: In addition to the infrastructure under its own purview, MSA provides all support services for the contractor/utility interface. These activities include formulation and submission of incentive-based efficiency projects, project tracking, and incentive awards. All incentive awards are forwarded to the relevant contractor and then highlighted in the visibility campaign. Successful energy efficiency projects at Hanford have included high efficiency heating, ventilation, air conditioning (HVAC) systems, interior and exterior lighting/lighting control systems, pump and motor systems, and the right-sizing of transformers and area-wide electrical distribution systems. Prior to the initiation of this program and structure (roughly 3 years ago) the average annual energy efficiency incentive applied for and received was under $10,000, with an annual energy savings of approximately 36,000 kilowatt hours (kWh). In fiscal year 2017, the annual incentive received was over $419,000, with identified energy savings of over 1.3 million kWh. Details and case studies of the major project accomplishments are included. The success of this program can be traced to an understanding of the constraints, the development of a program to address these constraints, and good communication/coordination across DOE and the multiple contractors serving the Hanford site. (authors)
[en] The development of the quantum Hall effect in condensed matter physics that breaks time-reversal symmetry by magnetic biasing has inspired its analog in classical nonreciprocal acoustics. Nonreciprocal acoustic propagation is highly desirable to control acoustics in isolation, broadband unidirectional transmission, and topologically robust to structural disorders or defects. So far, these fascinating properties have been investigated through fan-induced moving media, acoustic capacitance adjustment and acoustic metamaterials. However, these may be associated with disadvantages including extra noise and limited dynamic controlling performance. Here we overcome these limitations by introducing heat-induced natural convection into acoustic circulator, and demonstrate that the classical acoustic circulator with thermal management can realize robust nonreciprocal acoustic propagation. The concept of combining heat-induced natural convection and aeroacoustics creates a new practical paradigm and increases the feasibility for nonreciprocal acoustics due to merits of dynamic control, versatile topological structures, and miniaturization in the absence of moving parts. (paper)
[en] Currently, the main embedded storage system supplying the electric vehicles is composed of Li-ion batteries. The electrical characteristics information's provided by the battery manufacturers (power, energy and capacity) are reliable; it is not the same for aging. Indeed, the lifetime gave by manufacturers is estimated on the basis of charge / discharge tests at constant current, while aging is a criterion which depends strongly on the real use conditions. This thesis is one of the common themes of work that ESTACA leads in collaboration with L2EP about the electric vehicles research projects. The objective of this work is to study the interest of a hybrid source composed of Li-ion batteries and supercapacitors to supply an urban electric vehicle and evaluate the impact of hybridization on the Li-ion batteries lifetime. Firstly, an energy management strategy based on deterministic rules is developed to control the power between the battery and supercapacitor. To demonstrate the combination utility, different Li-ion battery technologies (Li-ion high power, high-Li-ion energy) are used on the sizing step. Through this study, we could propose an optimal solution (masses, volumes, costs, autonomy...) consisting of an energetic battery and supercapacitor. This study also shows that the batteries power type do not need hybridization, when the high energy batteries cannot supply the vehicle without hybridization with the supercapacitors. The second part of this thesis evaluates the hybridization contributions in terms of aging. In this case, we have followed the evolution of capacity and the internal resistance losses of high power and high energy batteries type in, respectively, single-source and hybrid configurations. For this study, a test bench, developed for cycling and characterization of storage systems, was used. The results obtained provide the opportunity to choose Li-ion battery technology that could be the most interesting for the supply of electric vehicles. (author)
[fr]Actuellement, la principale source d'energie embarquee dans les vehicules electriques est composee de batteries Li-ion. Bien que les donnees fournies par les constructeurs de batteries sur les caracteristiques electriques (puissance, energie et capacite nominale) de leur produit, soient fiables et exploitables, il n'est pas de meme pour le vieillissement. En effet, la duree de vie fournie par les constructeurs est estimee sur la base des essais de charge/decharge a courant constant, alors que le vieillissement est un critere qui depend vigoureusement des conditions reelles d'utilisation. Cette these fait partie des thematiques communes de travail que mene L'ESTACA en collaboration avec le L2EP pour realiser des projets R et D sur la chaine de traction des vehicules electriques. L'objectif ce projet est d'etudier l'apport d'une source hybride composee de batteries Li-ion et des supercondensateurs, sur les performances d'un vehicule electrique urbain et d'evaluer l'impact de l'hybridation sur la duree de vie des batteries Li-ion. Dans un premier temps, une strategie de gestion des flux energetiques entre la batterie et le supercondensateur basee sur l'approche des regles deterministes a ete appliquee pour montrer l'interet de l'association des differentes technologies de batterie Li-ion (haute puissance, haute energie) avec le supercondensateur en fonction de l'autonomie. Cette methode nous a permis de montrer l'avantage de l'hybridation pour certaines technologies et la non-necessite d'une hybridation pour d'autres. A travers cette etude, on a pu proposer une solution optimale (masses, volumes, couts, autonomie,... composee d'une batterie energetique et un supercondensateur. La deuxieme partie de cette these est consacree a l'evaluation de l'apport de l'hybridation en termes de duree de vie. Dans ce cas, on a suivie l'evolution du vieillissement des deux batteries de type haute puissance et hautes energie dans, respectivement, les configurations mono-source et hybride. Pour realiser cette etude, un banc de tests, destine au cyclage et la caracterisation des systemes de stockage, a ete utilise. Les resultats obtenus, offriront la possibilite de se prononcer sur le type de batteries Li-ion qui pourrait etre le plus interessant pour l'alimentation des vehicules electriques. (auteur)
[en] The debate on effective climate protection is heating up in Germany and the rest of the world. Nuclear energy is being touted as “clean” energy. Given the circumstances, the present study analyzed the historical, current, and future costs and risks of nuclear energy. The findings show that nuclear energy can by no means be called “clean” due to radioactive emissions, which will endanger humans and the natural environment for over one million years. And it harbors the high risk of proliferation. An empirical survey of the 674 nuclear power plants that have ever been built showed that private economic motives never played a role. Instead military interests have always been the driving force behind their construction. Even ignoring the expense of dismantling nuclear power plants and the long-term storage of nuclear waste, private economy-only investment in nuclear power plant would result in high losses - an average of five billion euros per nuclear power plant, as one financial simulation revealed. In countries such as China and Russia, where nuclear power plants are still being built, private investment does not play a role either. Nuclear power is too expensive and dangerous; therefore it should not be part of the climate-friendly energy mix of the future.