Simulation of demand side participation in Spanish short term electricity markets

Demand response resources management is one of the most investigated solutions oriented to improve the efficiency in electricity markets. In this paper, the capability of customers to participate in short term markets is analyzed. An available methodology to analyze the daily and monthly energy consumptions of large customers is used to create energy offers and bids. This allows customers to participate in energy markets in order to buy, as first step, the usual electricity consumption and, additionally, to offer demand reductions in the short term electricity markets. Additionally, this paper shows the customer potential to participate in the Spanish electricity markets.Valencia Salazar, I.; Álvarez Bel, CM.; Escrivá Escrivá, G.; Alcázar Ortega, M. (2011). Simulation of demand side participation in Spanish short term electricity markets. Energy Conversion and Management. 52(7):2705-2711. doi:10.1016/j.enconman.2011.02.005S2705271152

El mecanismo de transmisión de los tipos de interés en España : estimación basada en desagregaciones sectoriales

Ofrece estimaciones sectoriales del mecanismo de transmision monetaria en España. Utilizando la metodologia VAR, se cuantifican los efectos que un impulso monetario exogeno tiene sobre las variables intermedias y finales que son el objetivo de la politica monetaria. Partiendo de que la separacion entre instrumento (exogeno) y variables objetivo (endogenas) intermedias y finales es factible, se ofrecen estimaciones significativas del tamaño y velocidad de los efectos de una perturbacion monetaria sobre el nivel de actividad y los precios, y se aporta informacion sobre los mecanismos dominantes a traves de los cuales se propagan los efectos de la politica monetaria. Este ejercicio resulta particularmente relevante cuando la conduccion de la politica monetaria se basa en la fijacion de objetivos en terminos de una variable intermedia. Incluye bibliografia.(jeb)(ah)(jha

Renewable generation and demand response integration in micro-grids: development of a new energy management and control system

The aim of this research resides in the development of an energy management and control system (EMCS) to control a micro-grid based on the use of renewable generation and demand resources to introduce the application of demand response concepts to the management of micro-grids in order to effectively integrate the demand side as an operation resource for the grid and improve energy efficiency of the elements. As an additional result, the evaluation of reductions in the total amount of CO2 emitted into the atmosphere due to the improvement of the energy efficiency of the system is assessed.Álvarez, C.; Escrivá-Escrivá, G.; Alcázar-Ortega, M. (2013). Renewable generation and demand response integration in micro-grids: development of a new energy management and control system. Energy Efficiency. 6(2):695-706. doi:10.1007/s12053-013-9207-9S69570662Alcázar-Ortega, M. (2011). “Evaluation and assessment of new demand response programs based on the use of flexibility in industrial processes: Application to the food industry”. Ph.D. Dissertation. University of South Florida and Universidad Politécnica de Valencia. FebruaryAlcázar-Ortega, M., Álvarez-Bel, C., Escrivá-Escrivá, G., & Domijan, A. (2012). Evaluation and assessment of demand response potential applied to the meat industry. Applied Energy, 92, 84–91.Álvarez Bel, C., Alcázar Ortega, M., Escrivá Escrivá, G., & Gabaldón Marín, A. (2009). Technical and economical tools to assess customer demand response in the commercial sector. Energy Conversion and Management, 50(10), 2605–2612.Álvarez, C., Gabaldón, A., & Molina, A. (2004). Assessment and simulation of the responsive demand potential in end-user facilities: application to a university customer. Institute of Electrical and Electronics Engineers Transactions on Power Systems, 19, 1223–1231.Amorim, A., Cardoso, A.L., Oyarzabal, J. and Melo, N. (2005). “Analysis of the Connection of a Microturbine to a Low Voltage Grid”. Future Power Systems, International Conference on 16–18 Nov. 2005 Page(s):1–5Chiu A., Ipakchi A., Chuang A., Qiu B., Brooks D., Koch E., et al. (2009), Framework for integrated demand response (DR) and distributed energy resources (DER) models. NAESB & UCAIug. September; 2009. .Cowart, R. (2001). “Efficient reliability, the critical role of demand-side resources in power systems and markets”. The national association of regulatory utility commissioners, junioDimeas, A. L., & Hatziargyriou, N. D. (2005). Operation of a multiagent system for microgrid control. Institute of Electrical and Electronics Engineers Transactions on Power Systems, 20(3), 1447–1455.Elgerd, O. (1982). Electric energy systems: theory and introduction. New York: McGraw-Hill.Escrivá, G., Alcázar,M., Alvarez,C. (2009). “Integral management system for the energy efficiency improvement in commercial facilities: Application to the Polytechnic University of Valencia”. International conference on renewable energy and power quality (ICREPQ’09), AprilEscrivá-Escrivá, G., Segura-Heras, I., & Alcázar-Ortega, M. (2010). Application of an energy management and control system to assess the potential of different control strategies in HVAC systems. Energy and Buildings, 42(11), 2258–2267.European Commission (2003), “New ERA for electricity in Europe”. Directorate General for Research.Ghiani, E. Mocci, S. and Pilo, F. (2005). “Optimal reconfiguration of distribution networks according to the microgrid paradigm”. Future Power Systems, International Conference on16-18 Nov. 2005 Page(s):6 ppGlover, J., Sarma, M., & Overbye, T. (2008). Power systems: analysis and design. Toronto: Thompson.Hatziargyriou, N.D., Dimeas, A., Tsikalakis, A.G., Pecas Lopes, J.A., Kariniotakis, G.G, and Oyarzabal, J. (2005). “Management of Microgrids in Market Environment”. Future Power Systems, International Conference on 16–18 Nov. Page(s):1 – 7.ICF Consulting. (2002). “Economic assessment of RTO policy Report”. FERC, mayo 2002.Jayawarna, N., Wu, S., Zhang, Y., Jenkins N. and Barnes, M. (2006). “Stability of a Microgrids”. Power Electronics, Machines and Drives. The 3rd IET International Conference on Mar. 2006 Page(s):316 – 320Kennedy, J., Fox, B., & Morrow, D. J. (2007). Distributed generation as a balancing resource for wind generation. IET Renewable Power Generation, 1(3), 167–174.Kirschen, D. S. (2003). Demand-side view of electricity markets. Institute of Electrical and Electronics Engineers Transactions, 18, 520–527.Kojima, Y., Koshio, M., Nakamura, S., Maejima, H., Fujioka, Y. and Goda, T. (2007). “A Demonstration Project in Hachinohe: Microgrids with Private Distribution Line”. System of Systems Engineering. SoSE ‘07. IEEE International Conference on 16–18 April 2007 Page(s):1 – 6Lasseter, R.H. and Piagi, P. (2007). “Extended Microgrids Using (DER) Distributed Energy Resources”. Power Engineering Society General Meeting. IEEE24- 28 June 2007 Page(s):1–5Lopes, J. A. P., Moreira, C. L., & Madureira, A. G. (2006). Defining control strategies for microgrids islanded operation. Institute of Electrical and Electronics Engineers Transactions on Power Systems, 21(2), 916–924.Marnay, C., Venkataramanan, G., Stadler, M., Siddiqui, M. A., Firestone, R. and Chandran, B. (2007). “Optimal Technology Selection and Operation of Microgrids in Commercial Buildings”. 67 Power Engineering Society General Meeting. IEEE 24–28 June 2007 Page(s):1 – 7Nikkhajoei, H. and Lasseter R.H. (2007). “Microgrids Protection”. Power Engineering Society General Meeting, 2007. IEEE 24–28 June Page(s):1 – 6Rassanti, S., Smith, V. and Wilson, B. (2001). “Controlling market power and price spikes in electricity networks: Demand-side bidding”. Interdisciplinary centre for economic science, George Mason University, JulyThe Federal Energy Regulatory Commission Staff: Draft for Comment of the National Action Plan on Demand Response. March; 2010. .Yunwei, L., Vilathgamuwa, D. M., & Poh Chiang, L. (2004). Design, analysis, and realtime testing of a controller for multibus microgrid system”. Institute of Electrical and Electronics Engineers Transactions on Power Electronics, 19(5), 1195–1204

Characterization of the gas-liquid interfacial waves in vertical upward co-current annular flows

[EN] For more than fifty years, hundreds of research works have focused on the study of annular flow because of its huge importance in many industrial processes, for instance, chemical, petroleum, etc., being of particular interest in nuclear industry. Specifically, interfacial waves play a vital role in the mass, momentum and energy transference processes between gas and liquid phases. This paper describes the new experimental measurements of vertical upward co-current two-phase gas-liquid flow carried out in a tube with an inner diameter of 44 mm. The liquid film thickness and the major characteristics of the interfacial waves have been measured using a non-intrusive instrument, a conductance probe. The physical phenomenon in which this device is based is the change in the electrical conductivity between air and water, i.e., the electrical signal collected in the sensor receiver depends on the thickness of the liquid film layer. The experimental measurements range from 2000 to 3500 l/min for the gas volumetric flow rate, and from 4 to 10 l/min for the liquid volumetric flow rate. Correlation of the experimental measurements of liquid film thickness and the major properties of the interfacial waves have been analyzed using non-dimensional numbers. An important part of the document focuses on the comparison of the experimental data and the fitting correlations against several of the most widely used expressions. Throughout this paper, in addition to present all the available correlations, the existing scattering found when comparing against other expressions have been also confirmed, underlining the existence of gaps of knowledge even today. Emphasize that the proposed correlations are the ones that better fit the data of all experimental series carried out under the present study for the analyzed variables, with almost all the experimental points covered by the +/- 10% error bands of the new correlations.The authors are indebted to the plan of I+D support of the EXMOTRANSIN project ENE2016-79489-C2-1-P.Cuadros-Orón, JL.; Rivera-Durán, Y.; Berna, C.; Escrivá, A.; Muñoz-Cobo, JL.; Monrós-Andreu, G.; Chiva, S. (2019). Characterization of the gas-liquid interfacial waves in vertical upward co-current annular flows. Nuclear Engineering and Design. 346:112-130. https://doi.org/10.1016/j.nucengdes.2019.03.008S11213034

Exploring the use of low-intensity ultrasonics as a tool for assessing the salt content in pork meat products

Meat industry demands non-destructive techniques for the control of the salting process to achieve a homogeneous final salt content in salted meat products. The feasibility of using low-intensity ultrasound for characterizing the salting process of pork meat products was evaluated. The ultrasonic velocity (V) and time of flight (TF) were measured by through-transmission and pulse-echo methods, respectively, in salted meat products. Salting involved an increase of the V in meat muscles and a decrease of the time of flight in whole hams. Measuring the V before and after salting, the salt content could be estimated. Moreover, online monitoring of the salting process by computing the TF could be considered a reliable tool for quality control purposesGarcía Pérez, JV.; Prados Pedraza, MD.; Martínez-Escrivá, G.; González, R.; Mulet Pons, A.; Benedito Fort, JJ. (2015). Exploring the use of low-intensity ultrasonics as a tool for assessing the salt content in pork meat products. Physics Procedia. 70:837-840. doi:10.1016/j.phpro.2015.08.171S8378407

Uso del debate como herramienta metodológica docente en estudios del Grado en Medicina: DEBATMITAL

[EN] The main purpose of the DEBATMITAL project is to increase the participation of students in the practical session on "Myths of Food" that is part of the optional subject “Nutrition and Dietetics" of the degree in Medicine of the University of Valencia. In front of the master class, which was basically the tool used in previous courses, students are organized into discussion groups to debate some food-related statements commonly heard. The assessment that students make of this initiative is very positive. They indicate that they have learned, they have had fun while participating in the debates, and that they prefer this tool to the master class. Therefore, the debate is a teaching tool that can not only be used in Social Sciences area, but can also be very useful for certain topics in Health Sciences, as in the case of the degree in Medicine.[ES] El proyecto DEBATMITAL tiene como objetivo principal aumentar la participación de los alumnos en la sesión práctica sobre “Mitos de la Alimentación” que forma parte de la asignatura optativa “Alimentación y Dietética” del grado en Medicina de la Universidad de Valencia. Frente a la clase magistral, que era básicamente la herramienta utilizada en cursos anteriores, se organiza la clase en grupos de debate para tratar diversas afirmaciones relacionadas con la alimentación que se pueden escuchar comúnmente. La valoración que los estudiantes hacen de esta iniciativa es muy positiva. Indican que han aprendido, que se han divertido mientras participaban en los debates, y que prefieren esta herramienta a la clase magistral. Por tanto, el debate es una herramienta docente que no solo se puede utilizar en el área de las Ciencias Sociales, sino que también puede ser muy útil para determinados temas en grados del área de Ciencias de la Salud, como es el caso del grado en Medicina.Olaso-González, G.; Romá-Mateo, C.; Serna García, E.; Gambini, J.; Correas, ÁG.; Gimeno, L.; Escrivá, C.... (2019). Uso del debate como herramienta metodológica docente en estudios del Grado en Medicina: DEBATMITAL. En IN-RED 2019. V Congreso de Innovación Educativa y Docencia en Red. Editorial Universitat Politècnica de València. 1022-1033. https://doi.org/10.4995/INRED2019.2019.10471OCS1022103

Uso de la infografía en la optativa “Alimentación y Dietética” del Grado de Medicina

[ES] Como sustitución de la clase magistral, en la sesión dedicada a tratar las características de “dietas occidentales de moda” de la asignatura optativa 34493-Alimentación y Dietética del Grado en Medicina de la Universitat de Valencia, se utilizaron infografías previamente diseñadas por los estudiantes. Con esta iniciativa se pretendía mejorar la participación del alumnado en la asignatura, además de profundizar en la materia, mejorar sus habilidades digitales y de búsqueda y síntesis de información. Esta propuesta fue bien valorada por el estudiantado, que mostró su preferencia por esta forma de trabajar frente a la clase magistral. Además, opinó que la actividad mejoraba su capacidad de transmitir información, de trabajar en equipo, su capacidad crítica y autocrítica y que resultaba muy entretenida. A partir de esta experiencia se podría concluir que la infografía es una herramienta útil para el abordaje de varios temas dentro del grado de Medicina.[EN] As a substitute for the master class, infographics previously designed by the students were used in the session dedicated to treating the characteristics of "fashionable western diets" of the optional subject 34493-Food and Dietetics of the Bachelor Degree in Medicine at the Universitat de Valencia. This initiative was intended to improve student participation in the subject, in addition to deepening the subject, improving their digital skills and the search and synthesis of information. This proposal was well appreciated by the students, who showed their preference for this way of working compared to the master class. In addition, they said that the activity improved their ability to transmit information, to work as a team, their critical and self-critical capacity and that it was very entertaining. From this experience, it could be concluded that infographics are a useful tool for addressing various topics within the Medicine degree.Olaso González, G.; Borras, C.; Piqueras, M.; Romá Mateo, C.; Gambini, J.; Gomez-Cabrera, MC.; G. Correas, Á.... (2020). Uso de la infografía en la optativa “Alimentación y Dietética” del Grado de Medicina. En IN-RED 2020: VI Congreso de Innovación Educativa y Docencia en Red. Editorial Universitat Politècnica de València. 193-207. https://doi.org/10.4995/INRED2020.2020.11954OCS19320

Aging in Male Wistar Rats Associates with Changes in Intestinal Microbiota, Gut Structure, and Cholecystokinin-Mediated Gut-Brain Axis Function

Aging in mammals is characterized by failure of the homeostatic mechanisms that regulate energy balance. Several mechanisms have been proposed such as the presence of a low-grade chronic inflammation in different tissues, as well as leptin and insulin resistance, but the primary alteration is not fully elucidated. The gut microbiota has recently emerged as a key player in a variety of metabolic and neurological disorders. A main concept in this context is the gut–brain axis that refers to alterations in the gut that mediate effects in the central nervous system, including those related with the control of energy balance. Using 16S rRNA analysis, we demonstrate that aged male Wistar rats have increased presence of mucin-degrading and lipopolysaccharide (LPS)-producing bacteria. In addition, old animals exhibit a lower number of neutral mucin secreting goblet cells, and a decrease of tight junctions and adherens junctions marker proteins, zonula occludens protein-1 (ZO-1) and β-catenin, respectively. These data are compatible with a thinner mucus layer and a weaker gut barrier in older animals that likely facilitate LPS leakage. Our data also show that cholecystokinin (CCK) satiating effect is impaired in aged rats, one of the expected effects of increased LPS leakage. In contrast, no overt signs of gut or systemic inflammation are observed. Changes in microbiota in old male Wistar rats present features of situations of increased adiposity, but different from those of obese animals. These could partly explain the increased adiposity and fat deposition in liver and heart as observed here.Spanish Government (grants BFU2008-04901-C03-01/BFI to J.M.C., BIO2016-76601-C3-2-R to M.F.-L., and RTI2018-094052-B-100 [MCI/AEI/FEDER, UE to A.M.V.] and Centro de Investigación Biomédica en Red de Diabetes y Enfermedades Metabólicas (Instituto de Salud Carlos III) and Comunidad de Madrid, Spain (grants S2010/BMD-2423 to J.M.C., F.E., L.G.G., and A.M.V. and S2017/BMD-3684 to F.E. and A.M.V.). C.R. was supported by a predoctoral aid from Spanish Government. The Centro de Biología Molecular is recipient of institutional aids from Banco de Santander and Ramón Areces Foundation