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Energi merupakan bagian penting dalam keberlangsungan hidup. Kehidupan manusia tidak bisa lepas dari energi, terutama energi yang sering digunakan oleh masyarakat adalah energi listrik. Pemakaian listrik sering tidak diperhatikan oleh masyarakat yang menyebakan pembengkakan biaya. Tujuan dari alat ini dibuat adalah membantu masyarakat agar dapat memantau pola penggunaan daya pada perangkat elektronik di rumah dan biaya yang dihasilkan dari perangkat tersebut. Dengan menggunakan teknologi Internet of Things, masyarakat tidak perlu kesulitan dalam memantau biaya, hanya dengan memasang aplikasi pada smartphone. Teknologi Internet of Things yang diterapkan disini adalah menggunakan sensor PZEM-004T sebagai aktuator dan ESP8266 sebagai perangkat mikrokontroler pengendali. Data yang dipantau adalah penggunaan daya, arus, tegangan, dan biaya yang dihasilkan selama 5 hari percobaan. Pengujian dilakukan untuk mendapatkan pola penggunaan daya dari perangkat elektronik yang diuji dan menentukan working periode dari perangkat tersebut. Hasil penelitian menunjukan tingkat akurasi alat ini mencapai diatas 95% dan perbandingan antara standar deviasi dengan reratai rill melebihi 95% Energy is an important part of survival. Human life cannot be separated from energy, especially the energy that is often used by society is electrical energy. The use of electricity is often not considered by the community which causes cost overruns. The purpose of this tool is to help people monitor power usage patterns on electronic devices at home and the costs generated from these devices. By using Internet of Things technology, people don't need to have trouble monitoring costs, just by installing an application on a smartphone. The Internet of Things technology applied here uses the PZEM-004T sensor as the actuator and the ESP8266 as the controlling microcontroller device. The monitored data is the use of power, current, voltage, and costs generated during the 5 trial days. Tests are carried out to obtain patterns of power usage from the tested electronic devices and determine the working period of these devices. The results showed that the accuracy of this tool reached above 95% and the comparison between the standard deviation and the real average exceeded 95%.

1. INTRODUCCIÓN................................................................2 2. MATERIALES Y METODOS.........................................................4 2.1. Diseño experimental............................................4 2.2. Material biológico..........................................................5 2.2.1. Caracterización de los residuos del plátano...................5 2.2.2. Obtención y procesamiento de la biomasa...................5 2.3. Preparación del medio nutritivo...............................6 2.4. Determinación de la eficiencia de la CCM...................7 2.4.1. Evaluación del desempeño electroquímico.............7 2.4.2. Construcción y operación de la CCM.......................7 2.5. Análisis de datos.........................................................8 2.6. Análisis estadístico de datos...........................9 3. RESULTADOS Y DISCUSIÓN............................................10 3.1. Estimación de los residuos de la postcosecha del cultivo de plátano.......10 3.2. Rendimiento energético de las CCM..................11 3.3. Análisis estadístico de los datos obtenidos........................17 4. CONCLUSIONES ...................................................17 El aumento de la población a nivel mundial conlleva un aumento en el consumo de energía eléctrica, por lo que actualmente se hace necesario buscar fuentes de energía que contribuyan a suplir la demanda energética con el menor impacto ambiental. Teniendo en cuenta que los residuos más abundantes a la hora de la postcosecha del cultivo de plátano es el pseudotallo se utilizó este como sustrato. Se evaluó el efecto de la variación de parámetros como la concentración de biomasa el cual fue de 5,2 g/l y 10g/l, y el electrolito en el puente salino los cuales fueron NaCl y KCl en la generación de potencia. La energía total generada y la potencia máxima alcanzada por las configuraciones 5,2 g/l NaCl fue de 8,66 kj/kg y 1,33e-5 W, para 10 g/l NaCl fue 3,96 kj/kg y 9,02e-6 W, para 5,2 g/l KCl fue de 2,06 kj/kg y 1,08e-5 W, y para la configuración 10 g/l KCl fueron de 3,98 kj/kg y un máximo de potencia de 1,15e-5 W. Se obtuvo que la configuración más óptima bajo estas condiciones fue la de 5,2 g/l NaCl debido a que esta produjo una mayor cantidad de energía, así como la mayor potencia. Esto indica que a bajas concentraciones de biomasa el NaCl produce más energía durante el tiempo de generación, mientras que para concentraciones bajas el KCl produce más energía que el NaCl. Se determinó mediante un análisis ANOVA que la concentración de biomasa, electrolito utilizado en el puente salino y la interacción entre estos dos factores afectan significativamente a la variable respuesta, energía total generada por unidad de masa en cada celda de combustible microbiana. Pregrado Ingeniero(a) Mecánico(a) Artículo

Neutrino oscillation experiments require a precise measurement of the neutrino energy. However, the kinematic detection of the final-state neutron in the neutrino interaction is missing in current neutrino oscillation experiments. The missing neutron kinematic detection results in a smaller detected neutrino energy than the true neutrino energy. A novel 3D-projection scintillator tracker, which consists of roughly ten million active cubes covered with an optical reflector, is capable of measuring the neutron kinetic energy and direction on an event-by-event basis using the time-of-flight technique thanks to the fast timing, fine granularity, and high light yield. The ν¯μ interactions tend to produce neutrons in the final state. By measuring the neutron kinetic energy, the ν¯μ energy can be reconstructed better, allowing a tighter incoming neutrino flux constraint. This article shows the detector’s ability to reconstruct neutron kinetic energy and the ν¯μ flux constraint achieved by selecting the charged-current interactions without mesons or protons in the final state. Neutrino oscillation experiments require a precise measurement of the neutrino energy. However, the kinematic detection of the final-state neutron in the neutrino interaction is missing in current neutrino oscillation experiments. The missing neutron kinematic detection results in a feed-down of the detected neutrino energy compared to the true neutrino energy. A novel 3D\textcolor{black}{-}projection scintillator tracker, which consists of roughly ten million active cubes covered with an optical reflector, is capable of measuring the neutron kinetic energy and direction on an event-by-event basis using the time-of-flight technique thanks to the fast timing, fine granularity, and high light yield. The $\bar{\nu}_{\mu}$ interactions tend to produce neutrons in the final state. By inferring the neutron kinetic energy, the $\bar{\nu}_{\mu}$ energy can be reconstructed better, allowing a tighter incoming neutrino flux constraint. This paper shows the detector's ability to reconstruct neutron kinetic energy and the $\bar{\nu}_{\mu}$ flux constraint achieved by selecting the charged-current interactions without mesons or protons in the final state.

Currently, fuel resources are depleting and this is increasing the demand for renewable energy sources. Most importantly, renewable energy sources do not cause any harm to the environment. Small hydropower plants are also included. For example, water going through a hydropower plant is not altered in any way and is available for agricultural use even after it had been used to generate electricity and the environment is not dependent on weather.

This study investigates the automotive magnetorheological (MR) shock absorber behaviour in conditions of changing temperature. Its temperature-dependent behaviour was quantified between ambient and maximal operating temperatures of the device. Aspects addressed include the temperature dependence of the control coil resistance in the absorber, the influence of operating current level on control coil temperature and the temperature dependence of the absorber force response and energy dissipation in the system. The results of experiments enabled us to evaluate the mechanical performance of the absorber at varied temperatures.

This thesis focuses on the study of fluid-structure interaction problems near to the free surface. The first part of the thesis is devoted to the study of the linear stability of a tensioned membrane in a uniform flow and parallel to the free surface so-called the "Nemtsov configuration". A numerical approach is implemented and the eigenvalue problem obtained is then solved using the StabFEM software developed at IMFT and based on the finite elements software FreeFEM++. The results extend the current literature associated with this configuration to finite values of the density ratio of the fluid and the solid, and show that this configuration is at the origin of different types of instabilities including classical fluid-structure instabilities such as static (divergence) and dynamic instabilities (flutter), as well as radiative instability specifically due to the presence of the free surface. The mechanisms at the base of this latter instability are described and interpreted as a competition between different types of surface waves called negative energy and positive energy which respectively have the effect of destabilizing and stabilizing the membrane when they are generated. In the perspective of the use of flexible structures for the wave energy harvesting, the second part of the thesis is dedicated to the study of the forcing by a monochromatic incident wave of an energy converter made up of a flexible membrane submerged parallel to the free surface in the presence of a current and connected to one (or more) punctual linear damper(s) modeling the energy extraction. The set of equations modeling this wave-current-flexible membrane interaction problem is then solved numerically using StabFEM software. Our method is then compared to the results of the literature in order to validate the inclusion of flexibility and incident current. The effect of the incident flow (waves / current) on the efficiency of energy harvesting is studied for a converter with given characteristics (immersion, structural properties and fixed dimensions). The study reveals in particular that the presence of a current can significantly increase the efficiency of wave energy recovery. Subsequently, a parametric study of the main parameters of the energy recuperator (position and damping coefficient) is made for two typical incident waves (the wavelength / membrane length ratios are of the order of 1 and 2) . We find that we have a better efficiency (which can exceed 90%) mainly when the damper is placed in the downstream part of the membrane (beyond the middle). Finally, we propose a linear stability analysis of the flow around a rigid and fixed two-dimensional cylinder, near to the free surface. A Linearized-Eulerian-Lagrangian Arbitrary method (L-ALE) is implemented to formulate this problem in a moving domain having a small deformation compared to the reference configuration. After obtaining the steady solutions of the Navier Stokes equations using an iterative Newton method in which a deformation field is computed at each iteration. We then proceed to the stability analysis of the obtained base flow. The calculation of the hydrodynamic forces exerted on the cylinder surface shows that the lift force decreases with the presence of the free surface while the drag force increases when the deformations of the surface become important. Moreover, the stability analysis shows that the presence of the free surface has an important influence on the stability thresholds. Indeed, we have a destabilizing effect which manifests itself by the modification of the wake structure generated behind the cylinder., Cette thèse porte sur l'étude des problèmes d'interaction fluide-structure au voisinage d'une surface libre. La première partie de la thèse est consacrée à l'étude de la stabilité linéaire d'une membrane tendue dans un écoulement uniforme et parallèle à la surface libre appelée « configuration de Nemtsov ». Une approche numérique est mise en œuvre et le problème aux valeurs propres obtenu est ensuite résolu à l'aide du logiciel StabFEM développé à l'IMFT et basé sur le logiciel éléments finis FreeFEM++. Les résultats étendent la littérature actuelle associée à cette configuration à des valeurs finies de rapport de densité entre le fluide et le solide, et montrent que cette configuration est à l'origine de différents types d'instabilités incluant les instabilités fluide-structure classiques telles que des instabilités statiques et dynamiques (flottement), ainsi qu'une instabilité radiative spécifiquement due à la présence de la surface libre. Les mécanismes à la base de cette dernière instabilité sont décrits et interprétés comme une compétition entre différents types d'ondes de surface dites à énergie négative et à énergie positive qui respectivement ont pour effet de déstabiliser et stabiliser la membrane lorsqu'elles sont générées. Dans la perspective de l'utilisation de structures flexibles pour la récupération d'énergie des vagues, la seconde partie de la thèse est dédiée à l'étude du forçage par une houle incidente monochromatique d'un convertisseur d'énergie constitué d'une membrane flexible immergée parallèlement à la surface libre en présence d'un courant et reliée à un (ou plusieurs) amortisseur(s) linéaire(s) ponctuel(s) modélisant l'extraction d'énergie. L'ensemble des équations modélisant ce problème d'interaction vague-courant-membrane flexible est ensuite résolu numériquement à l'aide du logiciel StabFEM. Notre méthode est par la suite confrontée aux résultats de la littérature afin de valider la prise en compte de la flexibilité et du courant incident. L'effet de l'écoulement incident (vagues/courant) sur l'efficacité de la récupération d'énergie est étudié pour un récupérateur aux caractéristiques données (immersion, propriétés structurelles et dimensions fixées). L'étude révèle notamment que la présence d'un courant peut augmenter significativement l'efficacité de la récupération d'énergie des vagues. Ultérieurement,une étude paramétrique des principaux paramètres du récupérateur d'énergie (position et coefficient d'amortissement) est faite pour deux ondes incidentes typiques (les rapports longueur d'onde/longueur de la membrane sont de l'ordre de 1 et 2). Nous constatons que nous avons un meilleur rendement (qui peut dépasser 90%) principalement lorsque l'amortisseur est placé dans la partie aval de la membrane (au-delà du milieu). Finalement, nous proposons une analyse de stabilité linéaire de l'écoulement autour d'un cylindre bidimensionnel, rigide, immobile et à proximité d'une surface libre. Une méthode Arbitraire Eulérienne-Lagrangienne-Linéarisée (L-ALE) est mise en œuvre pour formuler ce problème dans un domaine mobile présentant une faible déformation par rapport à la configuration de référence. Après obtention des solutions stationnaires des équations de Navier Stokes en utilisant une méthode itérative de Newton dans laquelle un champ de déformation du maillage est calculé à chaque itération, une analyse de stabilité linéaire de ce champ de base est effectuée. Le calcul des efforts hydrodynamiques exercés sur la surface du cylindre montre que la force de portance diminue avec la présence de la surface libre tandis que le force de traînée augmente lorsque les déformations de la surface deviennent importantes. Par ailleurs, l'analyse de stabilité nous montre que la présence de la surface libre a une influence importante sur les seuils de stabilité. En effet, nous avons un effet déstabilisant qui se manifeste par la modification de la structure du sillage généré derrière le cylindre.

When the monumental Paris Climate Agreement entered into force in 2015, countries pledged to limit global warming to well below 2 °C relative to 1990 levels by 2030 to ensure that planet Earth stays inhabitable to humankind. The near universal ratification of this legal document and the respective Nationally Determined Contributions demonstrated countries’ ambitions to significantly lower greenhouse gas emissions in this pursuit. A fundamental aspect of decarbonization will not only be the increased use of renewable energy sources, but also the infrastructure necessary to integrate these into existing electricity grids. One of the important cornerstones of this integration will be the use of high-voltage direct current (HVDC). However, HVDC has so far not sufficiently been discussed in the context of the energy transition and in what ways specifically it can assist governments in reaching climate targets. Therefore, this thesis aims to find how HVDC can support the integration of renewable energy sources and thereby facilitate the energy transition to mitigate global warming. This will be done by carrying out a technical analysis of HVDC to understand where its benefits and drawbacks lie as well as an examination of the economic feasibility, by relying on secondary literature describing break-even distances. An analysis of the existing legal frameworks based on legal texts as primary literature will allow for the identification of areas that necessitate improvement. In the final section, geopolitical implications of the previous findings will be derived.The variable nature and inflexible sites of renewable energy makes HVDC ideal for their grid integration. HVDC allows for higher use of renewable energy potential because it can be used to transport bulk power over large distances with lower losses and at lower costs than high-voltage alternating current (HVAC) for the same distance. Furthermore, HVDC can be used to connect independent grids to allow for balancing of power in a system based largely on renewables with inherent fluctuations. The contributions towards this field lie in the identification of the reasons that HVDC will significantly contribute to the energy transition, thereby justifying increased consideration and investments, as well as suggestions for further necessary improvements in the field.

The continuous growth of population and energy-based industries have rapidly increased the demand on electricity and raised up the need for harmless and clean methods of electric energy generation and storage capacity. The world’s governments found it is feasible to consider the renewable energy sources as another alternative to supply part of their electrical needs. Renewable energy will minimize the environmental pollution associated with non-green methods of electrical generation which occupy the largest percentage of generation. Thus, photovoltaic systems along with large batteries have been implemented to generate and store electricity. These batteries have bad influences on the environment because they contribute in the pollution when they are manufactured and when they are out of use (i.e. they need recycling treatment). In this paper, we propose a schematic design of optimized water analysis-based cells that efficiently generate and safely store the energy as Hydrogen-Hydrogen Oxygen (HHO) ions. HHO cells promote a green energy generation and storage since clean water is the chemicals that is release out of burning this fuel. The HHO ions will be used as a clean energy source that can run most energy consuming systems. Hence, HHO ion generation will be another alternative to improve the storage of renewable energy.

Статья посвящена изучению методов и способов моделирования параметров элементов солнечных батарей, а также оцениванию эффективности их работы. Прикладные особенности работы элементов солнечной батареи рассмотрены на примере панели ФСМ-200М. Детально проанализирован порядок расчета вольтамперной характеристики солнечного элемента, который показывает зависимость выходного тока солнечного элемента от напряжения на его контактах. Также обозначены условия для эффективной работы солнечных элементов. Особое внимание уделено проведению анализа влияния на температуру солнечной панели внешних условий, в частности, температуры окружающей среды. С использованием полученных данных исследована зависимость солнечной инсоляции от углов наклона панели к солнцу. Кроме того, рассмотрено влияние на КПД солнечной панели толщины элементов., The paper focuses on methods for modeling the parameters of solar cell elements, as well as evaluating the effectiveness of their work. Applied features of solar battery elements operation are considered on the example of the FSM-200M solar panel. The procedure for calculating the current-voltage characteristics of the solar cell is analyzed in detail. The output current of the solar cell is shown to be dependent on the voltage at its contacts. The conditions for the effective operation of solar cells are also defined. Particular attention is paid to the analysis of the influence on the temperature of the solar panel of external conditions, in particular, ambient temperature. Using the derived data, the dependence of solar insolation on the angle of the panel relative to the sun was studied. In addition, the influence on the efficiency of the thickness of the solar cell element was determined., №1(43) (2020)

This is the data descriptor for the South African Domestic Electrical Load (DEL) study datasets. The DEL datasets were collected during the National Rationalised Specification Load Research Programme from 1994 to 2014. The datasets contain metered household electricity consumption data, and socio-demographic survey data for a diverse sample population spanning urban, informal and rural environments, five climatic zones, a large spectrum of income groups, newly to long-term electrified households, and different dwelling structures in South Africa and Namibia.