http://hdl.handle.net/2117/3323 Thu, 23 May 2013 07:38:01 GMT 2013-05-23T07:38:01Z webmaster.bupc@upc.edu Universitat Politècnica de Catalunya. Servei de Biblioteques i Documentació no http://hdl.handle.net/2117/18691 Title: Optimal electricity market bidding strategies considering emission allowances Authors: Corchero García, Cristina; Heredia, F.-Javier (Francisco Javier); Cifuentes, Julián Abstract: There are many factors that influence the day-ahead market bidding strategies of a GenCo in the current energy market framework. In this work we study the influence of both the allowances and emission reduction plan and the in- corporation of the derivatives medium-term commitments in the optimal generation bidding strategy to the day-ahead electricity market. Two different technologies have been considered: the coal thermal units, high-emission technology, and the combined cycle gas turbine units, low-emission technology. The operational characteristics of both kinds of units are modeled in detail. We deal with this problem in the framework of the Iberian Electricity Market and the Spanish National Emissions and Allocation Plans. The economic implications for a GenCo of including the environmental restrictions of these National Plans are analyzed Mon, 08 Apr 2013 10:54:18 GMT http://hdl.handle.net/2117/18691 2013-04-08T10:54:18Z Corchero García, Cristina; Heredia, F.-Javier (Francisco Javier); Cifuentes, Julián no There are many factors that influence the day-ahead market bidding strategies of a GenCo in the current energy market framework. In this work we study the influence of both the allowances and emission reduction plan and the in- corporation of the derivatives medium-term commitments in the optimal generation bidding strategy to the day-ahead electricity market. Two different technologies have been considered: the coal thermal units, high-emission technology, and the combined cycle gas turbine units, low-emission technology. The operational characteristics of both kinds of units are modeled in detail. We deal with this problem in the framework of the Iberian Electricity Market and the Spanish National Emissions and Allocation Plans. The economic implications for a GenCo of including the environmental restrictions of these National Plans are analyzed http://hdl.handle.net/2117/18369 Title: Optimal sizing of microgrids: a fast charging station case Authors: Corchero García, Cristina; Cruz Zambrano, Miguel; Heredia, F.-Javier (Francisco Javier); Cairo Molins, Josep Ignasi; Igualada Gonzalez, Lucia; Romero Ortega, Aitor Abstract: In this work we focus on the optimal design of electric vehicle charging stations. We consider investment, operational costs, physical constraints and different electricity pricing strategies. The size of the various components in the microgrid architecture and the suitability of the storage system are analysed. The electric vehicle charging demand is modelled through a queuing system. Mon, 18 Mar 2013 13:03:39 GMT http://hdl.handle.net/2117/18369 2013-03-18T13:03:39Z Corchero García, Cristina; Cruz Zambrano, Miguel; Heredia, F.-Javier (Francisco Javier); Cairo Molins, Josep Ignasi; Igualada Gonzalez, Lucia; Romero Ortega, Aitor no charging station, electric vehicle, energy storage system, microgrid components optimal size, queuing system In this work we focus on the optimal design of electric vehicle charging stations. We consider investment, operational costs, physical constraints and different electricity pricing strategies. The size of the various components in the microgrid architecture and the suitability of the storage system are analysed. The electric vehicle charging demand is modelled through a queuing system. http://hdl.handle.net/2117/17774 Title: Nonlinear network flows with side constraints applied to short term hydrothermal coordination of electricity generation Authors: Heredia, F.-Javier (Francisco Javier); Nabona Francisco, Narcís Thu, 14 Feb 2013 18:09:53 GMT http://hdl.handle.net/2117/17774 2013-02-14T18:09:53Z Heredia, F.-Javier (Francisco Javier); Nabona Francisco, Narcís no http://hdl.handle.net/2117/17410 Title: Present and future research on controlled tabular adjustment Authors: Castro Pérez, Jordi; González Alastrué, José Antonio Abstract: Controlled tabular adjustment (CTA) can be classi ed within the group of approaches that perturb output data (i.e., tabular data), unlike other methods that focus on the original microdata. Being a post-tabular data perturbation technique it becomes easier to guarantee consistency and quality of the released information (e.g., table additivity, preservation of subtotal or total cells of the original table, etc.). On the other hand, it may be computationally more costly than pre-tabular strategies. The purpose of this work is twofold. First, we will review a recently used heuristic to suboptimally solve CTA (which is a mixed integer linear optimization problem). For some tables this heuristic provided decent solutions much faster than other state-of-the-art optimization methods. This approach can be useful when CTA is applied to a pre-de ned "static" set of tables. The second goal of the paper is to provide and discuss variants of CTA when applied in an on-line table generation system. In this case, tables can be dynamically generated over time, and CTA has to face two new challenges: (i) it has to deliver an on-line fast solution; (ii) protection senses of sensitive cells have to be consistent (i.e, the same) when the same sensitive cell appears in two (or more) tables which are generated and protected at di erent moments. Some of these ideas will be implemented in the recently started Data without Boundaries FP7 EU project. Thu, 17 Jan 2013 17:57:13 GMT http://hdl.handle.net/2117/17410 2013-01-17T17:57:13Z Castro Pérez, Jordi; González Alastrué, José Antonio no Controlled tabular adjustment (CTA) can be classi ed within the group of approaches that perturb output data (i.e., tabular data), unlike other methods that focus on the original microdata. Being a post-tabular data perturbation technique it becomes easier to guarantee consistency and quality of the released information (e.g., table additivity, preservation of subtotal or total cells of the original table, etc.). On the other hand, it may be computationally more costly than pre-tabular strategies. The purpose of this work is twofold. First, we will review a recently used heuristic to suboptimally solve CTA (which is a mixed integer linear optimization problem). For some tables this heuristic provided decent solutions much faster than other state-of-the-art optimization methods. This approach can be useful when CTA is applied to a pre-de ned "static" set of tables. The second goal of the paper is to provide and discuss variants of CTA when applied in an on-line table generation system. In this case, tables can be dynamically generated over time, and CTA has to face two new challenges: (i) it has to deliver an on-line fast solution; (ii) protection senses of sensitive cells have to be consistent (i.e, the same) when the same sensitive cell appears in two (or more) tables which are generated and protected at di erent moments. Some of these ideas will be implemented in the recently started Data without Boundaries FP7 EU project. http://hdl.handle.net/2117/15925 Title: Rounding methods for protecting EU-aggregates Authors: Giessing, Sarah; Hundepool, Anco; Castro Pérez, Jordi Abstract: In the European Statistical System the statistical information is collected by the National Statistical Institutes (NSIs). The NSIs produce aggregate tables at the national level. They are also responsible for proper protection of these tables and hence they have to keep certain cells confidential, suppressing them from publications. Eurostat produces statistical information at the EU-level. However, the national suppressions hamper very much the publication of EU-aggregates although it is often only a few smaller countries having to keep their contribution to the EU-total confidential. This paper reports on a research-project that aims for making more EU aggregates available whilst at the same time guaranteeing the national suppressed figures to remain confidential. Thu, 24 May 2012 18:30:50 GMT http://hdl.handle.net/2117/15925 2012-05-24T18:30:50Z Giessing, Sarah; Hundepool, Anco; Castro Pérez, Jordi no In the European Statistical System the statistical information is collected by the National Statistical Institutes (NSIs). The NSIs produce aggregate tables at the national level. They are also responsible for proper protection of these tables and hence they have to keep certain cells confidential, suppressing them from publications. Eurostat produces statistical information at the EU-level. However, the national suppressions hamper very much the publication of EU-aggregates although it is often only a few smaller countries having to keep their contribution to the EU-total confidential. This paper reports on a research-project that aims for making more EU aggregates available whilst at the same time guaranteeing the national suppressed figures to remain confidential. http://hdl.handle.net/2117/14936 Title: Network model of short-term optimal hydrothermal power flow with security constraints Authors: Chiva, A; Heredia, F.-Javier (Francisco Javier); Nabona Francisco, Narcís Abstract: Optimizing the thermal production of electricity in the short term in an integrated system when a thermal unit commitment has been decided means coordinationg hydro and thermal generation costs over the time period under study. Fundamental constraints to be satisfied are the covering of each hourly load and satisfaction os spinning reserve requeriments and transmission capacity limits. A nonlinear network flow model with side constraints whit no decomposition into hysro and thermal subproblems was used to solve the hydrothermal scheduling. A novel thermal generation and transmission network is replicated with line outaged in order to obtain a secure multi-interval shot-term power flow. Computational results are reported. Fri, 03 Feb 2012 18:53:46 GMT http://hdl.handle.net/2117/14936 2012-02-03T18:53:46Z Chiva, A; Heredia, F.-Javier (Francisco Javier); Nabona Francisco, Narcís no Optimizing the thermal production of electricity in the short term in an integrated system when a thermal unit commitment has been decided means coordinationg hydro and thermal generation costs over the time period under study. Fundamental constraints to be satisfied are the covering of each hourly load and satisfaction os spinning reserve requeriments and transmission capacity limits. A nonlinear network flow model with side constraints whit no decomposition into hysro and thermal subproblems was used to solve the hydrothermal scheduling. A novel thermal generation and transmission network is replicated with line outaged in order to obtain a secure multi-interval shot-term power flow. Computational results are reported. http://hdl.handle.net/2117/14587 Title: Efficient solution of optimal multimarket electricity bid models Authors: Corchero García, Cristina; Heredia, F.-Javier (Francisco Javier); Mijangos Fernández, Eugenio Abstract: Short-term electricity market is made up of a sequence of markets, that is, it is a multimarket enviroment. In the case of the Iberian Energy Market the sequence of major short-term electricity markets are the day-ahead market, the ancillary service market or secondary reserve market (henceforth reserve market), and a set of six intraday markets. Generation Companies (GenCos) that participate in the electricity market could increase their benefits by jointly optimizing their participation in this sequence of electricity markets. This work proposes a stochastic programming model that gives the GenCo the optimal bidding strategy for the day-ahead market (DAM), which considers the benefits and costs of participating in the subsequent markets and which includes both physical futures contracts and bilateral contracts. Tue, 17 Jan 2012 08:48:27 GMT http://hdl.handle.net/2117/14587 2012-01-17T08:48:27Z Corchero García, Cristina; Heredia, F.-Javier (Francisco Javier); Mijangos Fernández, Eugenio no Short-term electricity market is made up of a sequence of markets, that is, it is a multimarket enviroment. In the case of the Iberian Energy Market the sequence of major short-term electricity markets are the day-ahead market, the ancillary service market or secondary reserve market (henceforth reserve market), and a set of six intraday markets. Generation Companies (GenCos) that participate in the electricity market could increase their benefits by jointly optimizing their participation in this sequence of electricity markets. This work proposes a stochastic programming model that gives the GenCo the optimal bidding strategy for the day-ahead market (DAM), which considers the benefits and costs of participating in the subsequent markets and which includes both physical futures contracts and bilateral contracts. http://hdl.handle.net/2117/11203 Title: Non experimental evaluation of a computer assisted tool Authors: Cobo Valeri, Erik; González Alastrué, José Antonio; Muñoz Gracia, María del Pilar; Dieguez, José Manuel; Piñeiro, Martiño Abstract: E-status is a web-based tool designed to improve learning in statistics introductory courses. On a separate research (Gonzalez et al, 2006) we present an experimental evaluation on the performance improvement among students of a dentistry school. Here, on an observational setting, we estimate its effect on improving the learning level of an introductory statistical course of 84 lecturing hours (6 European Credit Transfer System) for computer science students. Tue, 25 Jan 2011 16:02:35 GMT http://hdl.handle.net/2117/11203 2011-01-25T16:02:35Z Cobo Valeri, Erik; González Alastrué, José Antonio; Muñoz Gracia, María del Pilar; Dieguez, José Manuel; Piñeiro, Martiño no E-status is a web-based tool designed to improve learning in statistics introductory courses. On a separate research (Gonzalez et al, 2006) we present an experimental evaluation on the performance improvement among students of a dentistry school. Here, on an observational setting, we estimate its effect on improving the learning level of an introductory statistical course of 84 lecturing hours (6 European Credit Transfer System) for computer science students. http://hdl.handle.net/2117/8967 Title: Tanteando a Bolonia: unas experiencias sobre cómo implicar al alumno Authors: González Alastrué, José Antonio; Cobo Valeri, Erik; Rius Carrasco, Roser Abstract: Los nuevos planes de estudio del EEES se ponen en marcha, y las asignaturas deben introducir los cambios metodológicos sugeridos por Bolonia. Describimos nuestra experiencia en una asignatura perteneciente a un plan de estudios anterior, pero donde en su última edición hemos ensayado algunas iniciativas para estimular el trabajo activo del alumno. Una de las propuestas ha consistido en organizar cooperativamente el diseño de un estudio para comparar las velocidades observada y contratada de la conexión doméstica a internet. Básicamente, en un foro de la intranet de la facultad de informática, profesores y alumnos han diseñado la recogida de la información. Los datos obtenidos (p.ej.: la velocidad real está un 20% por debajo de la contratada) han alimentado el interés y la discusión crítica de los alumnos. El ejercicio, voluntario y sin repercusión en la calificación por esta vez, ha logrado un grado de implicación notable entre el alumnado, y merece ser repetido en cursos posteriores. Mon, 20 Sep 2010 11:15:44 GMT http://hdl.handle.net/2117/8967 2010-09-20T11:15:44Z González Alastrué, José Antonio; Cobo Valeri, Erik; Rius Carrasco, Roser no Los nuevos planes de estudio del EEES se ponen en marcha, y las asignaturas deben introducir los cambios metodológicos sugeridos por Bolonia. Describimos nuestra experiencia en una asignatura perteneciente a un plan de estudios anterior, pero donde en su última edición hemos ensayado algunas iniciativas para estimular el trabajo activo del alumno. Una de las propuestas ha consistido en organizar cooperativamente el diseño de un estudio para comparar las velocidades observada y contratada de la conexión doméstica a internet. Básicamente, en un foro de la intranet de la facultad de informática, profesores y alumnos han diseñado la recogida de la información. Los datos obtenidos (p.ej.: la velocidad real está un 20% por debajo de la contratada) han alimentado el interés y la discusión crítica de los alumnos. El ejercicio, voluntario y sin repercusión en la calificación por esta vez, ha logrado un grado de implicación notable entre el alumnado, y merece ser repetido en cursos posteriores. http://hdl.handle.net/2117/8691 Title: E-status: a web tool for learning by doing exercises Authors: González Alastrué, José Antonio; Muñoz Gracia, María del Pilar Abstract: The paper introduces the project led by a team of teachers to assist students learn statistics. The goal is to build a tool able to present mathematical problems and to correct the students´ answers. The problems may include random data, so the solution cannot be previously known (if solved before) and the student can reconsider it if necessary. Pedagogical implications are commented, since the method can be effective on the basic and middle domains of learning, as well as on higher levels, specially if careful design of the problems is applied. Mon, 30 Aug 2010 12:19:44 GMT http://hdl.handle.net/2117/8691 2010-08-30T12:19:44Z González Alastrué, José Antonio; Muñoz Gracia, María del Pilar no The paper introduces the project led by a team of teachers to assist students learn statistics. The goal is to build a tool able to present mathematical problems and to correct the students´ answers. The problems may include random data, so the solution cannot be previously known (if solved before) and the student can reconsider it if necessary. Pedagogical implications are commented, since the method can be effective on the basic and middle domains of learning, as well as on higher levels, specially if careful design of the problems is applied. http://hdl.handle.net/2117/8427 Title: Using discrete-event simulation to design reliable and cost-efficient civil engineering structures Authors: Juan Pérez, Angel Alejandro; Ferrer Biosca, Alberto; Serrat Piè, Carles; Faulín, Javier; Hester, J.; López Brosa, Pere Abstract: In this paper the topic of Structural Reliability Analysis and its importance in modern Civil Engineering is introduced. Throughout the paper, some advantages that simulation-based approaches offer with respect to other classical approaches are discussed. After a review of the most relevant literature on the subject, a simulation-based approach is described. Our methodology makes use of discrete-event simulation techniques to help the civil engineer design more reliable and cost-efficient structures. A numerical example illustrates some potential applications of the proposed methodology. Finally, potential research and academic applications of this approach are also discussed. Tue, 27 Jul 2010 11:55:44 GMT http://hdl.handle.net/2117/8427 2010-07-27T11:55:44Z Juan Pérez, Angel Alejandro; Ferrer Biosca, Alberto; Serrat Piè, Carles; Faulín, Javier; Hester, J.; López Brosa, Pere no In this paper the topic of Structural Reliability Analysis and its importance in modern Civil Engineering is introduced. Throughout the paper, some advantages that simulation-based approaches offer with respect to other classical approaches are discussed. After a review of the most relevant literature on the subject, a simulation-based approach is described. Our methodology makes use of discrete-event simulation techniques to help the civil engineer design more reliable and cost-efficient structures. A numerical example illustrates some potential applications of the proposed methodology. Finally, potential research and academic applications of this approach are also discussed. http://hdl.handle.net/2117/8410 Title: Applications of discrete-event simulation to reliability and availability assesment in civil engineering structures Authors: Juan Pérez, Angel Alejandro; Monteforte, A.; Ferrer Biosca, Alberto; Serrat Piè, Carles; Faulín, Javier Abstract: This paper discusses the convenience of predicting, quantitatively, time-dependent reliability and availability levels asso-ciated with most building or civil engineering structures. Then, the paper reviews different approaches to these problems and proposes the use of discrete-event simulation as the most realistic way to deal with them, specially during the design stage. The paper also reviews previous work on the use of both Monte Carlo simulation and discrete-event simulation in this area and shows how discrete-event simulation, in particular, could be employed to solve uncertainty in time-dependent structural reliability problems. Finally, a case study is developed to illustrate some of the concepts previously covered in the paper. Tue, 27 Jul 2010 09:09:22 GMT http://hdl.handle.net/2117/8410 2010-07-27T09:09:22Z Juan Pérez, Angel Alejandro; Monteforte, A.; Ferrer Biosca, Alberto; Serrat Piè, Carles; Faulín, Javier no This paper discusses the convenience of predicting, quantitatively, time-dependent reliability and availability levels asso-ciated with most building or civil engineering structures. Then, the paper reviews different approaches to these problems and proposes the use of discrete-event simulation as the most realistic way to deal with them, specially during the design stage. The paper also reviews previous work on the use of both Monte Carlo simulation and discrete-event simulation in this area and shows how discrete-event simulation, in particular, could be employed to solve uncertainty in time-dependent structural reliability problems. Finally, a case study is developed to illustrate some of the concepts previously covered in the paper. http://hdl.handle.net/2117/8393 Title: A decision support procedure for the short-term scheduling problem of a Generation Company operating on Day-Ahead and Physical Derivatives Electricity Markets Authors: Vespucci, M.-Teresa; Corchero García, Cristina; Innorta, Mario; Heredia, F.-Javier (Francisco Javier) Abstract: We consider a generation company operating in the liberalized electricity market, whose production system consists of hydro and thermal plants. Production is sold either directly to customers, by means of bilateral contracts, or on the spot market, where the electricity price is unknow until the market clearing process has taken place. Price risk may be hedged by financial tools provided by the Derivative Electricity Market. In this work futures contracts are considered, i.e. agreements to sell electricity in the future for a specified price. A Mixed Integer Linear Programming model is introduced for determining the unit commitment of thermal units and the dispatchment of available thermal units and hydro plants, aiming at maximizing profits. Numerical results on a case study are reported. Mon, 26 Jul 2010 09:46:29 GMT http://hdl.handle.net/2117/8393 2010-07-26T09:46:29Z Vespucci, M.-Teresa; Corchero García, Cristina; Innorta, Mario; Heredia, F.-Javier (Francisco Javier) no We consider a generation company operating in the liberalized electricity market, whose production system consists of hydro and thermal plants. Production is sold either directly to customers, by means of bilateral contracts, or on the spot market, where the electricity price is unknow until the market clearing process has taken place. Price risk may be hedged by financial tools provided by the Derivative Electricity Market. In this work futures contracts are considered, i.e. agreements to sell electricity in the future for a specified price. A Mixed Integer Linear Programming model is introduced for determining the unit commitment of thermal units and the dispatchment of available thermal units and hydro plants, aiming at maximizing profits. Numerical results on a case study are reported. http://hdl.handle.net/2117/8390 Title: Optimal day-ahead bidding strategy in the MIBEL's multimarket energy production system Authors: Corchero García, Cristina; Heredia, F.-Javier (Francisco Javier) Abstract: A Generation Company (GenCo) can participate in the Iberian Electricity Market (MIBEL) through different mechanisms and pools: the bilateral contracts, the physical derivatives products at the Derivatives Market, the bids to the Day-Ahead Market, the Intraday Markets or the Ancillary Services Markets. From the short-term generation planning point of view, the most important problem to solve is the bidding strategy for the Day- Ahead Market (DAM) given that the 85% of the physical energy traded in Spain is negotiated in it, but this participation cannot be tackled independently of other subsequent markets. Mon, 26 Jul 2010 09:35:06 GMT http://hdl.handle.net/2117/8390 2010-07-26T09:35:06Z Corchero García, Cristina; Heredia, F.-Javier (Francisco Javier) no A Generation Company (GenCo) can participate in the Iberian Electricity Market (MIBEL) through different mechanisms and pools: the bilateral contracts, the physical derivatives products at the Derivatives Market, the bids to the Day-Ahead Market, the Intraday Markets or the Ancillary Services Markets. From the short-term generation planning point of view, the most important problem to solve is the bidding strategy for the Day- Ahead Market (DAM) given that the 85% of the physical energy traded in Spain is negotiated in it, but this participation cannot be tackled independently of other subsequent markets. http://hdl.handle.net/2117/8335 Title: Optimal bidding strategies for thermal and combined cycle units in the day-ahead electricity market with bilateral contracts Authors: Heredia, F.-Javier (Francisco Javier); Rider Flores, Marcos Julio; Corchero García, Cristina Abstract: This paper developed a stochastic programming model that integrated the most recent regulation rules of the Spanish peninsular system for bilateral contracts in the dayahead optimal bid problem. Our model allows a price-taker generation company to decide the unit commitment of the thermal and combined cycle programming units, the economic dispatch of the BC between all the programming units and the optimal sale bid by observing the Spanish peninsular regulation. The model was solved using real data of a typical generation company and a set of scenarios for the Spanish market price. The results are reported and analyzed. Thu, 22 Jul 2010 09:10:22 GMT http://hdl.handle.net/2117/8335 2010-07-22T09:10:22Z Heredia, F.-Javier (Francisco Javier); Rider Flores, Marcos Julio; Corchero García, Cristina no This paper developed a stochastic programming model that integrated the most recent regulation rules of the Spanish peninsular system for bilateral contracts in the dayahead optimal bid problem. Our model allows a price-taker generation company to decide the unit commitment of the thermal and combined cycle programming units, the economic dispatch of the BC between all the programming units and the optimal sale bid by observing the Spanish peninsular regulation. The model was solved using real data of a typical generation company and a set of scenarios for the Spanish market price. The results are reported and analyzed.