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electricidad, energía hidroeléctrica, patrimonio industrial, electricity, hydroelectric power, and industrial heritage

Reseña de un libro sobre la principal obra hidráulica construida por la Mexican Light and Power a partir de 1903. La empresa fue fundada por Fred Stark Pearson para abastecer de energía eléctrica a Ciudad de México y al centro del país. El libro trata de valorar el patrimonio industrial del municipio en que se encuentra localizado, destacando su importancia para la identidad y el desarrollo, y colaborando con un proyecto colectivo de la comunidad local.
Review of a book about the main hydraulic work built by the Mexican Light and Power since 1903. The company was founded by Fred Stark Pearson to supply electricity to Mexico City and the center of the country. The book tries to assess the industrial heritage of the municipality in which it is located, highlighting its importance for identity and development, and collaborating with a collective project of the local community

Electricity, Magnetism, Conceptual understanding, Multiple-choice instrument, Reliability analysis, Electricidad, Magnetismo, Entendimiento conceptual, Instrumento de opciones múltiples, and Análisis de confiabilidad

The Conceptual Survey of Electricity and Magnetism (CSEM) has been widely used in the field of physics education. However, to date, no study presents a version of the test in Spanish. This article has three general objectives: 1) to present the CSEM in Spanish and analyze its reliability and discriminatory power, 2) to perform a detailed analysis of the most frequent difficulties of the students in the concepts evaluated in the test, and 3) to establish recommendations for research and instruction of these concepts. The test was implemented to 310 students who finished an Electricity and Magnetism course in a Mexican university. Researchers or physics professors from Spanish-speaking countries may use the test in Spanish that we present in the PhysPort project (physport. org); and the analysis and recommendations for instruction in this study.
La prueba The Conceptual Survey of Electricity and Magnetism (CSEM) ha sido ampliamente utilizada en el área de la educación de la física. Sin embargo, hasta la fecha no existe un estudio que presente el test en su versión en español. Este artículo tiene tres objetivos generales: 1) presentar el CSEM en su versión en español y analizar la confiabilidad y poder discriminatorio de este, 2) realizar un análisis detallado de las dificultades más frecuentes de los estudiantes en los conceptos evaluados en el test y 3) establecer recomendaciones para la investigación e instrucción de estos conceptos. El test fue implementado a 310 estudiantes que terminaban el curso Electricidad y Magnetismo de una universidad mexicana. El test en su versión en español, que presentamos en el proyecto Physport (physport. org), los análisis y las recomendaciones para la instrucción pueden ser utilizados por investigadores o por profesores de física de países hispanohablantes.

gas, electricidad, historia empresarial, Gas, Electricity, and Business history

El artículo aborda la trayectoria de Gaz Franco-Belge. Robert Lesage et Cie. (Cie. Franco-Belge), fundada en Bélgica en 1880, en Sanlúcar de Barrameda. En 1883, se inauguró la iluminación pública de gas y en 1919 cesó su actividad. Esta iniciativa corresponde a una generación efímera de empresas gasistas de matriz extranjera de ámbito municipal. En apariencia, se inscribiría en una tanda de inversiones poco razonables en mercados urbanos insuficientemente desarrollados, que acabaron de liquidar la competencia con la electricidad y las restricciones a las industrias consumidoras de carbón durante la Gran Guerra. Aquí, se defiende que el "privilegio" exclusivo de iluminación pública fue en realidad una condena en tanto el Consistorio se convirtió en el usuario principal y, al mismo tiempo, en la única fuente de regulación del mercado gasista en la ciudad. Sin intención ni de aumentar los impuestos ni de pagar este servicio público, se anclaba a las empresas concesionarias a negocios poco rentables, en localidades con rentas medias bajas.
This article focuses on the trajectory of Gaz Franco-Belge. Robert Lesage et Cie (Cie Franco- Belge), founded in Belgium in 1880, in Sanlúcar de Barrameda. Public gas lighting was inaugurated in 1883 and the company ceased its activity in 1919. This initiative may be included in an ephemeral generation of foreign companies in charge of municipal lighting. Apparently, these foreign direct investments were unreasonable where urban markets were underdeveloped. Competition with electricity and the restrictions on coal consumption during World War I finished with these firms. Actually, the exclusive “privilege” of public lighting was a sentence as long as the town Hall became both the main user and the only source of market regulation. Without any intention of either raising taxes or paying for this public service, the councils anchored concessionaires companies to unprofitable businesses, in localities with a very low income average.

Gas, electricidad, consumo, España, Electricity, Consumption, and Spain

En este trabajo se aborda el estudio de dos energías básicas, gas y electricidad, desde la perspectiva de la demanda y bajo un enfoque comparativo. La fuente a utilizar será la Estadística del Impuesto sobre el consumo de luz de gas, electricidad y carburo de calcio, complementada/contrastada con otras (Estadística Minera, Datos estadísticos técnicos de las fábricas de gas españolas, monografías locales, etc.). Los principales aspectos que se tratarán serán su difusión geográfica, incardinándola en la modernización de las estructuras urbanas, y los niveles de gasto energético, insertado a su vez en los cambios generales de las pautas de consumo, ambos desde una doble perspectiva espacial y temporal. Todo ello se llevará a cabo en un marco cronológico clave, el primer tercio del siglo XX, lo que permitirá abrir nuevas perspectivas y debates acerca del modo concreto en que se llevó a cabo en España el proceso de transición energética del gas a la electricidad.
This paper deals with the study of two basic energies, gas and electricity, from a demand perspective, and under a comparative approach. The source that will be used is the Estadística del impuesto sobre el consumo de luz de gas, electricidad y carburo de calcio, which is complemented/ contrasted with others (Estadística Minera, Datos estadísticos técnicos de las fábricas de gas españolas, local monographs, etc). The main issues will be their geographical diffusion, placing it in the context of the modernization of urban structures, as well as the levels of energy expenditure, which are linked to the global changes in consumption patterns, both from a spatial and temporal perspective. All this will be carried out in a chronological framework, over the first third of the twentieth century, which will open new perspectives and debates about the specific way in which the process of energy transition from gas to electricity was carried out in Spain.

Electricidad, sistemas de tarificación, precios, España, siglo xx, Electricity, Rate Systems, Tariffs, Spain, and 20th Century

En 1934, 672 empresas eléctricas de toda España publicaron en los Boletines Oficiales provinciales y en el Butlletí Oficial de la Generalitat de Catalunya sus precios de venta de la energía destinada a fuerza. Estos datos nos permiten disponer de una información muy completa de los sistemas tarifarios utilizados por los productores y distribuidores de electricidad antes de la guerra civil así como también de los precios máximos y de los descuentos que ofrecían a sus clientes. En este artículo se analizan los precios y descuentos publicados desde una doble perspectiva, empresarial y territorial, con objeto de conocer el precio de la energía eléctrica para usos industriales en la España del momento. Las notables diferencias observadas en el precio de venta del kWh reflejan la existencia de un mercado eléctrico escasamente integrado y el importante papel que seguían desempeñando los pequeños y medianos productores y distribuidores de energía a la hora de suministrar fluido a miles de empresas de todo el país en vísperas de la Guerra Civil.
In 1934, a total of 672 electricity companies from all over Spain made public in the Boletines Oficiales of the provinces and in the Butlletí Oficial de la Generalitat de Catalunya their rate systems and selling prices for power. These data provide comprehensive information about the diverse pricing system used by producers and distributors of electricity in Spain before the Civil War as well as the maximum prices and discounts offered from them to their clients. This paper analyses these prices and discounts from a business and territorial point of view. The remarkable differences in the selling price of kWh among firms and places reflect the existence of a poorly integrated electricity market and the important role small and medium producers and distributors of energy still played when supplying electricity to thousands of consumers around the country on the eve of the Civil War.

llibres de text, electricitat, anàlisi del llenguatge, educació intercultural, textbooks, electricity, language analysis, intercultural education, libros de texto, electricidad, análisis del lenguaje, and educación intercultural

Aquesta tesi se centra essencialment en l'estudi de dues variables: el llenguatge de dos llibres de text quant a si afavoreix o no la comprensió explicativa, i les respostes dels estudiants quan s'utilitzen altres fonts d'informació complementària. La mostra pertany a dos països: Canadà i Pakistan, i com a metodologia es va utilitzar l'anàlisi documental i un disseny quasiexperimental. Els resultats apunten a la necessitat de millorar els llibres de text i el seu ús.
This thesis focuses primarily on the study of two variables: the language of two textbooks as to whether or not favors explanatory understanding, and the responses of the students when they use other sources for additional information. The sample belongs to two countries: Canada and Pakistan, and document analysis as a methodology and a quasi-experimental design was used. The results point to the need to improve textbooks and usage.
La presente tesis se centra esencialmente en el estudio de dos variables: el lenguaje de dos libros de texto en cuanto a si favorece o no la comprensión explicativa, y las respuestas de los estudiantes cuando utilizan otras fuentes de información complementaria. La muestra pertenece a dos países: Canadá y Pakistán, y como metodología se utilizó el análisis documental y un diseño cuasiexperimental. Los resultados apuntan a la necesidad de mejorar los libros de texto y su uso.

Guerra Civil Española, Electricidad, Producción, Historia empresarial, Spanish Civil War, Electricity, Production, and Business History.

La historia de la Compañía Eléctrica Mengemor durante la Guerra Civil Española (1936-1939) es interesante, ya que era una de las grandes eléctricas del país, y su dirección e instalaciones quedaron divididas hasta el final de la contienda, y buena parte de las mismas en el frente de batalla. Para cada bando (el republicano y el nacional) analizaré: quiénes y cómo la dirigieron, el estado de las instalaciones, cómo se repararon y la electricidad producida. En general, ésta creció en ambas zonas, gracias a la gestión realizada y los escasos daños sufridos.
The history of the electric company Mengemor during the Spanish Civil War (1936-1939) is interesting in that it was one of the main electric companies in Spain, and its management and installations were divided during the conflict, and a large part of these were on the front line. For each side in the conflict (the republicans and the nationalists) the following will be analyzed: how they were managed and by whom, the state of the installations, how they were repaired, and the electricity which was produced. In general, production grew in both zones. This can be explained by good management and the scarce damage inflicted on the installations.

ELECTRICITY, MARKET pricing, INVENTORIES, ECONOMIC seasonal variations, SUPPLY & demand, and ELECTRIC rates

We examine forward prices in a market where nonstorable inventory exacerbates the influence of seasonal and hourly variation in supply and demand, expected and unexpected, on the level and volatility of spot prices. We find strong evidence, unusual for a commodity, that the difference between contemporaneous forward and spot prices has power to forecast both the spot price change and the risk premium realized at delivery. Our evidence of a time-varying risk premium is consistent with expected hourly and seasonal variation in the needs of producers and retailers of electricity to hedge against extreme spot price decreases and increases, respectively. [ABSTRACT FROM AUTHOR]

Reports of recent fire accidents in the electronics and electric vehicles (EVs) industries show that thermal runaway (TR) reactions are a key consideration for the industry. Utilization of solid electrolytes (SEs) could be an important solution in to the TR issues connected to exothermic electrochemical reactions. Data on the thermal stability of modern SEs, ionic transport mechanisms, kinetics, thermal models, recent advances, challenges, and future prospects are presented in this review. Ceramic polymer nanocomposites are the most appropriate SEs for high‐temperature stable batteries (in the range of 80–200 °C). Hydrogels and ionogels can be employed as stable, flexible, and mechanically durable SEs for antifreeze (up to –50 °C) and high‐temperature (up to 200 °C) applications in supercapacitors. Besides the thermal safety features, SEs can also prolong the lifecycle of energy storage devices in next‐generation EVs, space devices, aviation gadgets, defense tools, and mobile electronics. [ABSTRACT FROM AUTHOR]

In this study, Ponceau S dye, which is one of the hazardous dyes found in industrial wastewater, was examined for hydrogen production in single chamber-free membrane-free microbial electrolysis cells at different concentrations (10–40 mg L−1). A gas content analysis (hydrogen, carbon dioxide, and methane) was measured daily using gas chromatography to determine the effects of the Ponceau S on hydrogen production levels. Hydrogen was successfully produced in the presence of Ponceau S dye, but the gas production levels were affected by the concentrations of Ponceau S. The maximum hydrogen production was measured as 18 mL at a concentration level of 20 mg L−1. Decolorization ratios of Ponceau S were in the range of 85–100%. Hydrogen production rates increased in the presence of Ponceau S (20 mg L−1); however, yield (%) of the production decreased when compared to the control group. The percentage of COD removal was 94.78% in the presence of 40 mg L−1 of Ponceau S. In conclusion, hydrogen can be generated using wastewaters contaminated with azo dyes such as Ponceau S, and decolorization of the dye can be achieved, simultaneously. [ABSTRACT FROM AUTHOR]

Purpose: This study aims to estimate the electric power production of the 20 MWp solar photovoltaic (PV) plant installed in the Adrar region, South of Algeria using minimal knowledge about weather conditions. Design/methodology/approach: In this study, simulation models based on linear and nonlinear approaches were used to estimate accurate energy production from minimum radiometric and meteorological data. Simulations have been carried out by using multiple linear regression (MLR) and artificial neural network (ANN) models with three basic types of neuron connection architectures, namely, feed-forward neural network, cascade-forward neural network (CNN) and Elman neural network. The performance is measured based on evaluation indexes, namely, mean absolute percentage error, normalized mean absolute error and normalized root mean square error. Findings: A comparison of the proposed ANN models has been made with MLR models. The performance analysis indicates that all the ANN-based models are superior in prediction accuracy and stability, and among these models, the most accurate results are obtained with the use of CNN-based models. Practical implications: The considered model will be adopted in solar PV forecasting areas as part of the operational forecasting chain based on numerical weather prediction. It can be an effective and powerful forecasting approach for solar power generation for large-scale PV plants. Social implications: The operational forecasting system can be used to generate an effective schedule for national grid electricity system operators to ensure the sustainability as well as favourable trading performance in the electricity, such as adjusting the scheduling plan, ensuring power quality, reducing depletion of fossil fuel resources and consequently decreasing the environmental pollution. Originality/value: The proposed method uses the instantaneous radiometric and meteorological data in 15-min time interval recorded over the two years of operation, which made the result exploits a fact that the energy production estimation of PV power generation station is comparatively more accurate. [ABSTRACT FROM AUTHOR]

Purpose: The purpose of this paper is to focus on two major areas of concern for the Photovoltaic (PV) system, i.e. power quality and maximum power point tracking (MPPT). Novel control strategies have been proposed for both these issues, and their respective superiorities over the existing techniques have been established. On the other hand, as far as MPPT is concerned, two limitations are found in the available techniques. One is the inability of effective MPPT in dynamic conditions where the environmental parameters changes very rapidly. Second one is the ineffective tracking of global maxima under partial shading conditions. Design/methodology/approach: Here, modified Kalman filtering approach has been applied for estimating the reference current of active power filter, incorporated for power quality improvement. The proposed Kalman algorithm introduces a weighted matrix, which advances the estimated values of state variables. This paper presents a simple and enhanced model-based (MB) MPPT algorithm that has the capability of tracking MPPT effectively in both these working conditions. The proposed MB algorithm uses the mathematical modelling, and based on precised estimation of parameters, it pre-determines the MPP analytically. Findings: It has been tested successfully for dynamic variations of insolation, temperature and partial shading, where all these three parameters are rigorously varied over the full scale of practical values. The results have been also investigated experimentally and compared with the simulated one. A close matching of both the results has been shown through the plots, which validates the effectiveness of proposed algorithms. Originality/value: This research paper is part of the original research work carried out in Lab. Simulated results are obtained in MATLAB/Simulink platform, whereas these are further validated experimentally on 2-KW panel constituted with all types of commercial products, namely, mono, poly and thin-film. [ABSTRACT FROM AUTHOR]

Purpose: The assessment of the achievement of the goal is data driven and uses analytical modeling of the forecasted demand and the projected electrical power generated capacities. The analysis is based on compiled granular observations and is compared to reported aggregated information. The model takes into account changes in demand patterns such as the increase in the use of electric cars, and decreased demand because of improving efficiencies and behind-the-meter generation. Design/methodology/approach: This case study is designed to examine one of the major goals of New York State (NYS) Governor Andrew Cuomo's energy plan, namely, that 50% of all electric generation will come from renewable energy resources by the year 2030. The aim is to compare the aspiration of the political policy with the reality of its implementation. Findings: The analyses describe a measurable gap between the achievement of the stated goal and the projected reality. The paper includes discussions on the nature of this gap and factors that could potentially further increase this deficit. Practical implications: In addition, the paper highlights the need to recognize the complexities of projecting the future and difficulty of developing aggressive contingencies given practical and political constraints. Originality/value: This paper provides a data-driven independent assessment of the NYS' current energy plan and highlights important issues for consideration if the political promise is ever to become a reality. [ABSTRACT FROM AUTHOR]

Purpose: Trading on electricity markets occurs such that the price settlement takes place before delivery, often day-ahead. In practice, these prices are highly volatile as they largely depend upon a range of variables such as electricity demand and the feed-in from renewable energy sources. Hence, the purpose of this paper is to provide accurate forecasts.. Design/methodology/approach: This paper aims at comparing different predictors stemming from supply-side (solar and wind power generation), demand-side, fuel-related and economic influences. For this reason, this paper implements a broad range of non-linear models from machine learning and draw upon the information-fusion-based sensitivity analysis. Findings: This study disentangles the respective relevance of each predictor. This study shows that external predictors altogether decrease root mean squared errors by up to 21.96%. A Diebold-Mariano test statistically proves that the forecasting accuracy of the proposed machine learning models is superior. Research limitations/implications: The performance gain from including more predictors might be larger than from a better model. Future research should place attention on expanding the data basis in electricity price forecasting. Practical implications: When developing pricing models, practitioners can achieve reasonable performance with a simple model (e.g. seasonal-autoregressive moving-average) that is built upon a wide range of predictors. Originality/value: The benefit of adding further predictors has only recently received traction; however, little is known about how the individual variables contribute to improving forecasts in machine learning. [ABSTRACT FROM AUTHOR]

Material failure by white-etching-cracks (WECs) can cause enormous economic costs. The formation of WECs emerges from the decomposition of the original, usually cementite-containing, microstructure. As small amounts of electric current can trigger this failure mechanism, we investigate the contribution of electric current to cementite decomposition. We applied ∼700 A/cm2 for two weeks at 60°C to a pearlitic Fe-0.74C (wt%) specimen. The comparison of the microstructure before and after showed no differences. Theoretical considerations support the conclusion that at this low temperature such electric current densities cannot directly cause cementite decomposition. Electric current could play an indirect role in the formation of WECs, however, by generating hydrogen from the lubricant which is known to accelerate WECs formation. [ABSTRACT FROM AUTHOR]

This paper compares the observed and simulated performance of a 11.2 kWp grid-connected rooftop solar PV system installed in SOA (Deemed to be University), Bhubaneswar, India. The system consists of 40 polycrystalline silicon modules tilted at an angle of 21° facing towards the south. The performance parameters were measured during 2015 and were analysed by using two software tools: PVSyst and HelioScope. The measured annual energy generated by the PV system was found to be 15.33 MWh. The predicted annual energy yield by PVSyst and HelioScope with Meteonorm-derived data was found to be 9.2% and 14.75% higher than the measured value, but the predicted energy yield by HelioScope with ISHRAE data is in close approximation to the measured annual energy yield. [ABSTRACT FROM AUTHOR]

The present study aims to Fabricate a promising Microbial Solar Cell (MSC) for electricity generation using (sludge, wastewater and mixed algae), two single chamber MSCs were applied, firstly the sludge and algae cell (SMSC) was used and factors such as pH, types of light source, temperature, configuration of electrode and mixing ratio have being studied. The best pH, light source, temperature, configuration of electrode, and mixing ratio of the sludge and algae experiment are found to be 7, sun light, 30 oC, square electrode, and 1:1 respectively would be used in the wastewater and algae cell (WWMSC) for finding the most effective substrates for electrical energy generation. By comparing the Voltage resulted from sludge Microbial Solar cell (SMSC) and wastewater Microbial Solar cell (WWMSC). It was found that (SMSC) produce higher electrical energy than (WWMSC) with a voltage equal to 180 mV. [ABSTRACT FROM AUTHOR]