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© 2024 Elsevier. This manuscript version is made available under the CC-BY-NC-ND 4.0 license http://creativecommons.org/licenses/by-nc-nd/4.0, Nowadays, the increase in electric power coverage worldwide is a priority scope of the study, where Microgrids (MG) emerge as feasible solutions to supply electricity. The use of MG to provide energy to isolated communities, especially its use as Isolated Multi-Microgrid (IMMG) systems, has become an object of study worldwide. Different control techniques have been developed to improve and optimize the energy management system (EMS) associated with an isolated MG and new alternatives for energy exchange between IMMGs. However, the geographical location of a possible implementation of an MG directly affects the optimal dimensioning, the operating cost, and the environmental impact, among others. In this context, this work proposes a novel design of an EMS based on a fuzzy logic controller focusing on power exchange between IMMG systems. The proposed EMS aims to minimize the consumption of fossil fuels, reduce the total energy wasted by the power generation units, and keep the state-of-charge of the energy storage system (ESS) at safe levels to extend its useful life. Moreover, an ESS state of health analysis is presented to determine its degradation over time when applying the proposed EMS. In addition, the proposed EMS considers the uncertainties in the disconnection of any MG, ensuring the independent operation of each one. Simulation results are performed for a case study of an isolated community in the Amazon region of Ecuador. For this purpose, a group of microgrids is considered in three different scenarios. In the first scenario, there is no power exchange between the microgrids. In the second scenario, the microgrids exchange power using a simple EMS based on a set of analytical rules, and in the third scenario, the microgrids exchange power using the proposed EMS. The results show an improvement in the overall performance of the third scenario compared to the first two, both in reducing the energy wasted by the PV system and in the cost of fossil fuel. Final, Peer Reviewed, Objectius de Desenvolupament Sostenible::7 - Energia Assequible i No Contaminant::7.1 - Per a 2030, garantir l’accés universal a serveis d’energia assequibles, confiables i moderns, Objectius de Desenvolupament Sostenible::7 - Energia Assequible i No Contaminant, Objectius de Desenvolupament Sostenible::11 - Ciutats i Comunitats Sostenibles, Objectius de Desenvolupament Sostenible::11 - Ciutats i Comunitats Sostenibles::11.1 - Per a 2030, assegurar l’accés de totes les persones a habitatges i a serveis bàsics adequats, segurs i assequibles, i millorar els barris marginal, Objectius de Desenvolupament Sostenible::7 - Energia Assequible i No Contaminant::7.1 - Per a 2030, garantir l’accés universal a serveis d’energia assequibles, confiables i moderns, Objectius de Desenvolupament Sostenible::11 - Ciutats i Comunitats Sostenibles, Objectius de Desenvolupament Sostenible::7 - Energia Assequible i No Contaminant, Objectius de Desenvolupament Sostenible::11 - Ciutats i Comunitats Sostenibles::11.1 - Per a 2030, assegurar l’accés de totes les persones a habitatges i a serveis bàsics adequats, segurs i assequibles, i millorar els barris marginal, Postprint (author's final draft)

Philippe C. Schmitter (born 1936) has done path-breaking work within many different research fields where interest groups play important roles. This includes studies on neo-functionalism and European Union politics, public policy in Latin America, and global democratization processes. Still, he has primarily become strongly associated with the concept of corporatism, which describes a particular form of relationship between interest groups and the state (see chapter on “Corporatism (and Neo-corporatism)”). Schmitter characteristically combines his deep knowledge of classic political theory with insightful and innovative observations of real-life politics, providing thought-provoking new theoretical ideas. He formulates important critique directed at political science in general and democratic theory in particular, for their simplified assumptions about associations as political actors and state structures. This critique has significantly informed Schmitter’s work on corporatism and interest intermediation and profoundly changed interest group research as he demonstrated the limits of pluralism (see chapter on Pluralism) and other formerly dominating perspectives based on theories of liberal democracy. His thoughts on different modes of intermediation embedded in various contexts have inspired several generations of interest group researchers to continued renewal of the field. Schmitter has published his main contributions in journal articles or in book chapters in influential edited books, often with Schmitter himself as one of the co-editors. While this chapter focuses on his most important work on interest intermediation and corporatism, it is important to reemphasize that Schmitter has contributed to several other fields of research, most notably on democratization, for example, with his Transition from Authoritarian Rule. Tentative Conclusions about Uncertain Democracies (O’Donnell et al., 1986, co-authored with Guillermo O’Donnel and Lawrence Whitehead).

As smart grids develop, power systems become more complex, and the role of data gain considerable importance for the reliability of power supply. Thus, data processing techniques have to be investigated and compared to increase the efficiency of asset management decisions. In this paper, we explore several black-box models in order to predict power exchanges through a high-voltage direct-current line between Sweden and Denmark, using publicly available data on loads and power prices. An auto-regressive moving average with external input model based on load data provides the most accurate forecasts according to mean square error and other selected criteria. This is the first step to build a more comprehensive model that will also include other technical data such as maintenance and unplanned outages, but also macroeconomic factors. The final goal is to provide network operators with a parsimonious sequential model composed of several modules giving accurate predictions that support efficient asset management decisions., QC 20200702

In the deregulated framework in place in most power systems, a significant part of the energy is traded through auctions on day-ahead markets where agents submit bids to either buy or sell energy. When defining a bidding strategy, generators usually resort to models that anticipate and simulate agent interactions. The residual demand curve (RDC), a well-known approach to representing competitor behaviour, enables generators to formulate effective oligopolistic strategies. One way to estimate and build an RDC is to use information available about other agents' bids on previous and comparable days as a reference, This basic approach to market modelling has proven useful in the past in European power exchanges. In the current context, however, characterised by substantial market penetration on the part of non-dispatchable renewable resources, the suitability of this method of RDC building may need to be tested. This paper first analyses how the results of day-ahead auctions on European power exchanges have been affected by the growing penetration of renewable energy. It then questions both the use of RDC as an approach in this changing context and the aforementioned simplified estimation method to compute these curves. The discussion is illustrated with empirical evidence from the Iberian market.

In the deregulated framework in place in most power systems, a significant part of the energy is traded through auctions on day-ahead markets where agents submit bids to either buy or sell energy. When defining a bidding strategy, generators usually resort to models that anticipate and simulate agent interactions. The residual demand curve (RDC), a well-known approach to representing competitor behaviour, enables generators to formulate effective oligopolistic strategies. One way to estimate and build an RDC is to use information available about other agents' bids on previous and comparable days as a reference, This basic approach to market modelling has proven useful in the past in European power exchanges. In the current context, however, characterised by substantial market penetration on the part of non-dispatchable renewable resources, the suitability of this method of RDC building may need to be tested. This paper first analyses how the results of day-ahead auctions on European power exchanges have been affected by the growing penetration of renewable energy. It then questions both the use of RDC as an approach in this changing context and the aforementioned simplified estimation method to compute these curves. The discussion is illustrated with empirical evidence from the Iberian market.

В статье рассмотрены вопросы организации рынка электрической энергии и мощности в условиях его либерализации. Проведен анализ влияния либерализации энергетического рынка на характер функционирования промышленных предприятий. Предложена их классификация по возможности выхода на оптовый рынок электрической энергии и мощности. Выявлены особенности поведения предприятий на конкурентном рынке электрической энергии и мощности., The article examines major issues of electricity market arrangement under conditions of its liberalization. An analysis of power supply market liberalization influence on the functioning of industrial enterprises is conducted. Industrial enterprises are classified according to their ability to enter wholesale market of power suppliers. Peculiarities of behaviour of enterprises at a competitive power supply market are singled out.

The integration of large amounts of wind power into the energy system requires a strong interplay with power markets. In this respect the power exchange is an important instrument, defining a single market clearing price for each trading period. Following the liberalisation of the EU electricity industry power markets are increasingly being organised as power exchanges to a certain extent following the same lines, where a number of if not identical then closely related services are being provided. Using the NordPool power market as an example this chapter outlines the basic characteristics of the two key markets, the day-ahead market and the regulating market. The determination of the day-ahead price is described and the impact of wind power on power prices investigated. Finally, the cost of regulation is addressed., QC 20140513

The achievement of the internal market for energy is going ahead in the EU 15 since a model is emerging for “coupling the national markets for electricity”. For about 15 years the EU 15 was made up of national markets open to each other through rules of access to the grids while organized market pricing was kept national. The main exception was in the Nordic countries (Sweden, Finland and Denmark plus Norway –not a member of the EU). In this region the coupling of national markets is obtained through a single Power Exchange being a common subsidiary of the Nordic transmission system operators (TSOs). This single PX runs a single Day Ahead market pricing zone when the grid is not constrained and splits itself into different pricing areas when structural constraints arise. This model is known as “market splitting”. The Netherlands, Belgium and France did later create a less centralized single pricing mechanism by “coupling” their three national PXs with a common pricing algorithm coordinating the price formation among the three national exchanges. The empirical success of this new model has validated it as an EU model for other regional markets. A counter-model has been experimented between Germany and Denmark. It consisted of a coupling of “volumes” linking the quantities offered and demanded in the two exchanges while keeping the price formation in these two markets separated. That experiment failed and started to work again only when elements of price coupling have been introduced. Having now three workable models of market coupling, the European Union (at least EU 15) should be able to successfully achieve one layer of its internal market soon. However, several further questions are kept open such as how to successfully bridge several regional markets all over the EU 15 or how to integrate more and more PXs having different regulatory frames. A centralized approach (known as CMU) is advocating creating a single pan-European trading entity by a mandatory restructur

The achievement of the internal market for energy is going ahead in the EU 15 since a model is emerging for “coupling the national markets for electricity”. For about 15 years the EU 15 was made up of national markets open to each other through rules of access to the grids while organized market pricing was kept national. The main exception was in the Nordic countries (Sweden, Finland and Denmark plus Norway –not a member of the EU). In this region the coupling of national markets is obtained through a single Power Exchange being a common subsidiary of the Nordic transmission system operators (TSOs). This single PX runs a single Day Ahead market pricing zone when the grid is not constrained and splits itself into different pricing areas when structural constraints arise. This model is known as “market splitting”. The Netherlands, Belgium and France did later create a less centralized single pricing mechanism by “coupling” their three national PXs with a common pricing algorithm coordinating the price formation among the three national exchanges. The empirical success of this new model has validated it as an EU model for other regional markets. A counter-model has been experimented between Germany and Denmark. It consisted of a coupling of “volumes” linking the quantities offered and demanded in the two exchanges while keeping the price formation in these two markets separated. That experiment failed and started to work again only when elements of price coupling have been introduced. Having now three workable models of market coupling, the European Union (at least EU 15) should be able to successfully achieve one layer of its internal market soon. However, several further questions are kept open such as how to successfully bridge several regional markets all over the EU 15 or how to integrate more and more PXs having different regulatory frames. A centralized approach (known as CMU) is advocating creating a single pan-European trading entity by a mandatory restructur

The achievement of the internal market for energy is going ahead in the EU 15 since a model is emerging for “coupling the national markets for electricity”. For about 15 years the EU 15 was made up of national markets open to each other through rules of access to the grids while organized market pricing was kept national. The main exception was in the Nordic countries (Sweden, Finland and Denmark plus Norway –not a member of the EU). In this region the coupling of national markets is obtained through a single Power Exchange being a common subsidiary of the Nordic transmission system operators (TSOs). This single PX runs a single Day Ahead market pricing zone when the grid is not constrained and splits itself into different pricing areas when structural constraints arise. This model is known as “market splitting”. The Netherlands, Belgium and France did later create a less centralized single pricing mechanism by “coupling” their three national PXs with a common pricing algorithm coordinating the price formation among the three national exchanges. The empirical success of this new model has validated it as an EU model for other regional markets. A counter-model has been experimented between Germany and Denmark. It consisted of a coupling of “volumes” linking the quantities offered and demanded in the two exchanges while keeping the price formation in these two markets separated. That experiment failed and started to work again only when elements of price coupling have been introduced. Having now three workable models of market coupling, the European Union (at least EU 15) should be able to successfully achieve one layer of its internal market soon. However, several further questions are kept open such as how to successfully bridge several regional markets all over the EU 15 or how to integrate more and more PXs having different regulatory frames. A centralized approach (known as CMU) is advocating creating a single pan-European trading entity by a mandatory restructur

Financial derivatives are important hedging tool for asset’s manager. Electricity is by its very nature the most volatile commodity, which creates big incentive to share the risk among the market participants through financial contracts. But, even if volume of derivatives contracts traded on Power Exchanges has been growing since the beginning of the restructuring of the sector, electricity markets continue to be considerably less liquid than other commodities. This paper tries to quantify the effect of this insufficient liquidity on power exchange, by introducing a pricing equilibrium model for power derivatives where agents can not hedge up to their desired level. Mathematically, the problem is a two stage stochastic Generalized Nash Equilibrium and its solution is not unique. Computing a large panel of solutions, we show how the risk premium and player’s profit are affected by the illiquidity.

QC 20140811

A comprehensive analysis of the symmetric nonlinear directional coupler as a function of the excitation conditions is reported. The analysis is based on a coupled-mode technique in normalized (dimensionless) parameters, using the linear supermodes of the guiding structure, most of the results being derived from the Hamiltonian of the resulting nonlinear equations. The exchange of power between the branches in the coupler is graphically described by means of the trajectories of the motion in the phase space. The effect of saturation of the nonlinear index has been included., Peer Reviewed