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The coordination between system operators is a key element for the decarbonization of the power system. Over the past few years, many EU-funded research projects have addressed the challenges of Transmission System Operators (TSO) and Distribution System Operators (DSO) coordination by implementing different data exchange architectures. This paper presents a review of the ICT architectures implemented for the main coordination schemes demonstrated in such projects. The main used technologies are analyzed, considering the type of data exchanged and the communication link. Finally, the paper presents the different gaps and challenges on TSO-DSO coordination related to ICT architectures that must still be faced, paying especial attention to the expected contribution of the EU-funded OneNet project on this topic. IEEE CoordiNet H2020

Određivanje ekonomske štete u organizaciji predstavlja izazov jer organizacije često nisu svjesne koji sve izvori štete postoje pa je na početku rada dan pregled svih izvora štete nakon kibernetičkog napada. Oni su podijeljeni na izravne i neizravne izvore štete te detaljno opisani. Nakon toga je predstavljen Cyber Conflict Simulator u kontekstu definiranja formula za izračun ekonomske štetu unutar simulatora. Pomoću simulatora je napravljena simulacija napada i obrane na operator prijenosnog sustava te je pomoću formula definiranih u simulatoru i Python skripte izračunata ekonomska šteta za taj napad. Varirani su izvori štete te se pratila promjena ukupnog iznosa ekonomske štete te su se odredili izvori štete koji joj najviše pridonose. Determining the economic damage in an organization is a challenge because organizations are unaware of what sources of economic damage exist, so at the start of the thesis, there is a review of all damage sources after a cyber attack. They are divided into direct and indirect costs and described in detail. After that, the Cyber Conflict Simulator is presented in the context of defining formulas for calculating economic damage within the simulator. Simulation of an attack and defense on the transmission system operator is made, and the cost of that attack is calculated using equations in the simulator and Python script. The sources of damage are varied, the total amount of damage is monitored, and the origin of damage that contributed the most to it is determined.

Electrical power system operators (SOs) are free to realize grid operations according to their own strategies. However, because resulting power flows also depend on the actions of neighboring SOs, appropriate coordination is needed to improve the resulting system states from an overall perspective and from an individual SO perspective. In this paper, a new method is presented that preserves the data integrity of the SOs and their independent operation of their grids. This method is compared with a non-coordinated local control and another sequential method that has been identified as the most promising distributed optimization method in previous research. The time series simulations use transformer tap positioning as well as generation unit voltage setpoints and reactive power injections as flexibilities. The methods are tested on a multi-voltage, multi-SO, realistic benchmark grid with different objective combinations of the SOs. In conclusion, the results of the new method are much closer to the theoretical optimum represented by central optimization than those of the other two methods. Furthermore, the introduced method integrates a sophisticated procedure to provide fairness between SOs that is missing in other methods.

Replacing natural gas by hydrogen in the existing DSO infrastructure will give several challenges on the security of supply of energy to the end-users, related to the physical aspects of the assets in the hydrogen network. Within the HyDelta2 program, WP8 Digitalization, the need and benefit of digitalization of the gas grid has been investigated. In the current gas grid the digitalization is limited in all aspects: monitoring, modelling and control. This means that a lot of digitalization aspects could be developed to handle the needs of a future hydrogen grid, which have to deal with the following trends: increasing dynamics in supply and demand, from a stand-alone grid to a multi-connected grid and a need for real-time data on supply and demand. A roadmap has been developed on how to deal with the main challenges in balancing the future hydrogen grid, for all aspects of digitalization. In the frame of the HyDelta2 program we have chosen for the use case ‘Smart sensor placement’ for pressure and flow sensors in the Kapelle area, which covers the main digitalization aspects, with a focus on the short- and mid-term. On this grid several scenarios have been applied, using TNO’s dynamic gas grid simulation tool Aurora. Starting with a base case where natural gas is replaced by hydrogen. Subsequently scenarios have been simulated on adding new supply locations for electrolyzers with a dynamic profile, adding large consumers and a scenario with one ‘broken gas pipe’. The flow and pressure in the whole grid has been simulated for all scenario’s, with realistic supply and demand data. The gas grid simulator has been validated in the current (natural gas) situation by available pressure and flow data. By replacing the natural gas by hydrogen and maintaining the delivery of the same amount of energy to all users, the flows in the grid are about three times higher and the pressures will remain about the same. However, the flows stay below the allowable limits. In the case of adding two realistic electrolyzers with a total capacity of 3 MW, the maximum pressures stay below the allowable limits. A N-1 situation has been simulated by a pipe break in the 4 bar grid, showing the critical pipe segments where the pressure becomes too low. In the next scenario three additional large consumers are added, resulting in a pressure drop which is on some locations just below the allowable limit. Finally the effect of replacing the two current supply’s by one supply on another location in the grid, has been investigated. The simulation tool has been used to find the optimal locations in terms of pressures and flows within the acceptable limits. In all scenario’s an uncertainty in the domestic demand have been introduced and the number of (flow and pressure) sensors and their location have been determined, to minimize the uncertainty in flow and pressure in the whole grid. The overall picture for the scenario’s is that adding two sensors will give the main gain in reducing the uncertainty. Adding two pressure sensors reduces the uncertainty in pressure with about 60% to 70%. Adding flow sensors have a much smaller effect on the reduction due to restriction on placing the sensor. The location for placing the sensor is globally the same for all scenario’s. The different scenario’s show the need for a dynamic modelling tool that is able to calculate flows and pressures in the grid in case of a dynamic supply and demand situation. Only a tool will not be sufficient to get full insight, because of uncertainties in the input data for the grid. Besides uncertainty in the demand profile, there can be incompleteness of the geometrical information (pipe diameters, pipe roughness, etc.) and pressure settings which deviate from the numbers that are used in the model. So, to get a full insight in the grid, always measurement data will be needed. The benefit of a simulation tool to investigate the number and location of sensors has been demonstrated, showing that the number of pressure sensors in the grid should be increased. Furthermore, the insight in the physical behavior of the grid is essential in the future foreseen increase of the number of local decentralized hydrogen suppliers (both from solar/wind and surplus of the electricity grid) and the ability of DSO’s to control and manage the pressure in the distribution network. Overall, we can draw a conclusion on the added value of digitalization of the gas grid. The gas grid is currently facing several broad challenges which can be aided by digital technologies: different heating technologies, declining amount of customers and gas demand, converting of the grid to hydrogen (and biomethane) and decentralized production. Current standard operations such as maintenance planning and security of supply can benefit from digitalization, by allowing the DSO's to make better decisions and proper investments. Digitalisation will create more accurate and real-time insight and a combination of a robust calculation model and online data from a limited number of sensors will generate sufficient insight, moreover digitalisation will facilitate scenario analysis and creates more opportunities for renewable gasses in the gas network., Dit project is medegefinancierd door TKI Nieuw Gas | Topsector Energie uit de PPS-toeslag onder referentienummer TKI2022-HyDelta.

Liberalized gas markets in Europe are organized as entry-exit regimes so that gas trade and transport are decoupled. The decoupling is achieved via the announcement of technical capacities by the transmission system operator (TSO) at all entry and exit points of the network. These capacities can be booked by gas suppliers and customers in long-term contracts. Only traders who have booked capacities up-front can “nominate” quantities for injection or withdrawal of gas via a day-ahead market. To ensure feasibility of the nominations for the physical network, the TSO must only announce technical capacities for which all possibly nominated quantities are transportable. In this paper, we use a four-level model of the entry-exit gas market to analyze possible welfare losses associated with the decoupling of gas trade and transport. In addition to the multilevel structure, the model contains robust aspects to cover the conservative nature of the European entry-exit system. We provide several reformulations to obtain a single-level mixed-integer quadratic problem. The overall model of the considered market regime is extremely challenging and we thus have to make the main assumption that gas flows are modeled as potential-based linear flows. Using the derived single-level reformulation of the problem, we show that the feasibility requirements for technical capacities imply significant welfare losses due to unused network capacity. Furthermore, we find that the specific structure of the network has a considerable influence on the optimal choice of technical capacities. Our results thus show that trade and transport are not decoupled in the long term. As a further source of welfare losses and discrimination against individual actors, we identify the minimum prices for booking capacity at the individual nodes.

The increased penetration of distributed energy resources (DERs) has enhanced the importance of coordinated operation of transmission system operator (TSO) and distribution system operators (DSOs) in order to better exploit DERs. When TSO and DSOs coordinately operate to optimize overall performance of the system, it does not ensure that the benefit is attained by all participants. To ensure entering TSO and DSOs as subjective and self-interested agents’ coordinated operation, this article introduces a non-cooperative framework for coordinated operation of TSO and DSOs. In the proposed non-cooperative operation approach, TSO and DSOs are considered as subjective agents whose interest is to optimize their own objective functions selfishly while they are interactive and modify their solutions through exchanged boundary signals until the equilibrium is obtained. The effectiveness of the proposed non-cooperative operation approach has been demonstrated through many studies on two integrated test systems. Comparison of simulation results of applying the proposed non-cooperative approach with those of the cooperative ones demonstrates that although the optimal solution is achieved for the whole system in the cooperative operation, some agents cannot obtain a satisfactory solution. Thus, these agents prefer to enter a non-cooperative game with other agents. The proposed non-cooperative game leads to relative benefits for all agents.

The Dutch government’s central goal with the National Climate Agreement is to reduce net greenhouse gas emissions in the Netherlands by 55% by 2030 compared to 1990 levels and 100% by 2050. Hydrogen will carry out a number of critical functions within energy and raw material systems. The Distribution System Operators (DSO’s) in the Netherlands may play an important role delivering (green) hydrogen to the built environment via their existing gas transport network for sustainable heating of homes and business. Replacing natural gas by hydrogen in the existing DSO infrastructure will give several challenges (next to safety aspects, social acceptance, etc.) on the security of supply of energy to the end-users, related to the physical aspects of the assets in the hydrogen network. We would like to analyse where digital technology can contribute in accelerating the natural gas grid transformation. The scope of the research is limited to 100% hydrogen grids. As a research methodology to execute work we chose for the following approach: Get insight in the state of the art of digitalization of the current DSO gas grids, by sending a questionnaire and interviewing DSO representatives. The same questionnaire has been sent to TSO Gasunie to get a benchmark. Get insight in the needed digitalization of the future hydrogen grid. This was done by: Literature study, mainly regarding foreign DSO’s. A workshop with Dutch DSO representatives. Both the literature study and the outcome of the workshop with the DSO’s give an indication of the desired situation of digitalization of the (future) hydrogen grid.The concrete topics can be compared with the current situation regarding Modelling, Monitoring and Control. Within in the scope of this research, we will give a qualitatively description on the technology gap, and a (preliminary) prioritization of the gaps. Main results from the state of the art investigation for three systems are given below. Modelling All DSO’s use commercial tools for capacity calculation, designing the gas grid and determining risk levels regarding delivery. All capacity simulations are based on worst case scenario’s, like maximum demand at -12 or -13 °C. No dynamic hourly demand profiles are used. For risk analysis the N-1 approach (omitting one asset) is used, in most cases for design reasons. The tools are able to work with different gas compositions, but are only used for natural gas at this moment. For most DSO’s the capacity calculation tool is validated based on pressure measurement data at district stations and total flowrates at GOS. The data from measurements in the grid is not yet directly integrated to the capacity simulation tool. Currently the data is used as a manual input of the tool or by manually comparing the value in Excel table. Monitoring Pressure is the most common parameter being measured in the network. Mostly, there is no sensor placed in the pipeline, only a limited number of stations are being measured. Need for flow data has been observed and most DSO’s are working on that topic. Data from GOS and green gas suppliers is available. Most of data is manually accessed by the DSO by sending people to onsite location or a manual download from the website. Some station data of some DSO can be retrieved automatically via Remote Terminal Unit (RTU) unit. The use of smart meter data at small consumers is limited. Individual demand of small consumers is predicted by ‘Standaard JaarVerbruik’ (SJV) or by contract values for large consumer. Control The grid control at DSO’s is autonomous on pressure. The pressure setting is changed manually. The grid is robust with respect to capacity. DSO’s recognize no huge need for advanced control of the grid capacity in normal operation. More advanced control might be needed in some cases of green gas supply in the grid, e.g. boosters and dynamic pressure management. Most activities regarding Control are on green gas feed-in. Control is done by closing the valve in case of deviating gas quality. Manual control of the GOS pressure is done by request, to allow green gas feed-in in low demand period. From the workshop with the DSO’s we found the main challenge of operating a hydrogen grid is about balancing the hydrogen grid. There are several factors that contribute to this challenge: Increasing dynamics in supply and demand, like changing user profiles, increasing local supply and local storage and line-pack From a stand-alone gas grid to a multi-connection grid. Observed trends are: connection to other DSO’s, connection to Gasunie backbone and connection to E-grid (bi-directional) Get access to real time data, on both Demand and Supply. The workshop delivered many ideas on how to address the main challenges: Monitoring. Real-time data of Supply, Demand and Storage. Measurements in the grid (stations, pipes): Flow, Pressure, Quality and Temperature. Modelling. Real-time capacity models with coupling to externals: E-grid, Gasunie, other DSO’s. And tooling for short term transition planning from natural gas to hydrogen. Control. Controlling the priority of suppliers which can feed into the network. The main results of literature study on mainly foreign DSO’s are globally in line with the results from the Dutch state of the art investigation and the main outcomes of the workshop. Both the literature study and the outcome of the workshop with the DSO’s gives an indication of the desired situation of digitalization of the (future) hydrogen grid. Especially, the ‘HOW’ topics can be compared with the current situation to come to a qualitatively description on the technology gaps. From technology point of view we come to the following summary of the technology gap in digitalization of the hydrogen grid. Combining the technology readiness and timing, results in a preliminary prioritization of the technology gaps for modelling, monitoring and control. To provide more quantitively information regarding the development of the main technologies for digitalization of the hydrogen grid, in the second part of the current HyDelta 2 project we will investigate a selection of the gaps in use cases: Investigation on the number of flow sensors and pressure sensors needed in the grid. Investigate the added value of flow sensors? Investigation on the added value of using demand profiles and intermittent supply profiles for balancing the hydrogen grid using storage by utilizing producer priority and grid pressure regulation., Dit project is medegefinancierd door TKI Nieuw Gas | Topsector Energie uit de PPS-toeslag onder referentienummer TKI2022-HyDelta.

The aim of this article is to present and problematize perceptions of Justice System operators about police torture. The empirical material that underlies this paper was collected from thirty-seven semi-structured interviews conducted with judges, prosecutors and public defenders who work in the criminal area in Pernambuco. The data indicate that, for the interviewees, the Military Police, particularly its specialized battalions, is the organization that leads the practice of torture, which would happen during or as an offshoot of the policing activity on the street. The connection between trafficking arrests and the impacts of the transfer of investigative functions from the Civil Police to the Military Police for the dynamics of torture are discussed. It will also be presented the hypotheses that, for part of the bachelors heard in this research, torture would be a crime of opportunity and there would be a relationship between social class and the act of torturing. The study of the perceptions of legal professionals allows us to understand how those who decide the legal implications of police violence understand the phenomenon, drawing the attention of social scientists to the possibility of updating the organizational dynamics of police torture.

The increasing calls for decarbonization, and the consequent need for the energy system to integrate ever-increasing shares of renewable energy, place the electric grid at the core of an integrated, decarbonized energy system. This calls for Transmission System Operators (TSOs) and Distribution System Operators (DSOs) to fast-track the integration of clean energy solutions into the electric grid [1]–[3]. In this framework, whatever new management/business models can be envisaged for modern electric power systems, they must be based on the availability of suitable information. Consequently, the continuous evolution of applications in power grids stresses the need to define, develop, implement, and qualify innovative measurement components, devices, and systems for proper, effective, and efficient implementation of enhanced monitoring and control applications in electric transmission [1] and distribution [4] networks.

Republika Hrvatska zadovoljava manje od 25% potreba za prirodnim plinom iz vlastite proizvodnje te većinu uvozi s terminala za UPP i plinskog čvorišta CEGH. Transport od CEGH-a do Hrvatske može se odvijati kroz Mađarsku ili Sloveniju, a cijena transporta je važna stavka u formiranju nabavne cijena plina te je cilj opskrbljivača pronaći način kako što jeftinije transportirati plin. Za transport plina se zakupljuju transportni kapaciteti na interkonekcijama, a svaki operator transportnog sustava ima svoje tarifne stavke po kojima ih naplaćuje. Osim iz Austrije plin u Republiku Hrvatsku dolazi i s terminala za UPP na otoku Krku. Pri takvom načinu transporta prirodni plin ne prolazi kroz interkonekcije i transportne sustave drugih zemalja, već direktno s terminala ulazi u transportni sustav Republike Hrvatske pri čemu se zakupljuju samo transportni kapaciteti za ulaz s terminala za UPP. U ovom radu napravljena je analiza i usporedba troškova transporta prirodnog plina iz različitih dobavnih pravaca do Republike Hrvatske te je pokazano koji je od njih ekonomski najisplativiji., The Republic of Croatia meets less than 25% of its needs for natural gas through its own production and imports most of it from the LNG terminal and the CEGH gas hub. Transportation from the CEGH to Croatia can take place through Hungary or Slovenia and the price of transport is an important factor in the formation of the purchase price of gas. The goal of suppliers is to find a way to transport gas as cheaply as possible. For the transportation of gas, transport capacities are bought on interconnections, and each transmission system operator has its own tariff items according to which the prices are formed. Apart from Austria, natural gas also arrives to the Republic of Croatia from the LNG terminal on the island of Krk. Using this mode of transportation, natural gas does not pass through interconnections and transportation systems of other countries, but enters the transportation system of the Republic of Croatia directly from the terminal. Therefore, the only transport capacities bought for entry are purchased from the LNG terminal. This thesis will analyze and compare the costs of transporting natural gas using various supply routes to the Republic of Croatia and will determine which of them is economically most viable.

Integration of smart grid technologies in distribution systems, particularly behind-the-meter initiatives, has a direct impact on transmission network planning. This paper develops a coordinated expansion planning of transmission and active distribution systems via a stochastic multistage mathematical programming model. In the transmission level, in addition to lines, sitting and sizing of utility-scale battery energy storage systems and wind power plants under renewable portfolio standard policy are planned. Switchable feeders and distributed generations are decision variables in the distribution level while the impact of demand response programs as a sort of behind-the-meter technologies is accommodated as well. Expansion of electric vehicle taxi charging stations is included as a feasible option in both transmission and distribution levels. In order to deal with short-term uncertainty of load demand, renewable energy sources output power, and the charging pattern of electric vehicle taxis in each station, a chronological time-period clustering algorithm along with Monte Carlo simulation is utilized. The proposed model is tackled by means of Benders Dual Decomposition (BDD) method. The IEEE RTS test system (as the transmission system) along with four IEEE 33-node test feeders (as distribution test systems) are examined to validate effectiveness of the proposed model.

Дисертаційна робота викладена на 78 сторінках та складається із вступу, 5 розділів та загальних висновків. Робота включає в себе 11 рисунків, 18 таблиць, 6 джерел використаної літератури. В дисертації розглянуто питання балансування ринку електроенергії України. Проаналізовано стан системи передачі енергосистеми України, її проблеми та можливі шляхи вирішення. Обчислено параметри роботи енергосистеми України в нормальному режимі та при повному відключенні генеруючих потужностей Запорізької атомної елктростанції. Зроблено розрахунок електричної частини підстанції 750/330/10 кВ. Обрано релейний захист для шин 750 кВ. Розроблено cтартап-проєкт із розробки платформи для торгівлі електричною енергією між державами The dissertation is laid out on 78 pages and consists of an introduction, 5 chapters and general conclusions. The work includes 11 figures, 18 tables, 6 sources of used literature. The issue of balancing the electricity market of Ukraine is considered in the dissertation. The state of the transmission system of the energy system of Ukraine, its problems and possible solutions are analyzed. The parameters of Ukraine's energy system operation in normal mode and in case of complete shutdown of the generating capacities of the Zaporizhzhia nuclear power plant were calculated. The electrical part of the 750/330/10 kV substation was calculated. Relay protection for 750 kV buses is selected. A startup project has been developed to develop a platform for trading electric energy between states.

Configuration activities constitute a large part of the work in operating an IoT system. Such activities include the onboarding of devices and rollout of firmware updates. Configuration activities must be carefully vetted to prevent faulty states, putting a lot of pressure on IoT system operators to get it right. The problem is further exacerbated due to the heterogeneity, scalability, and distributed computation challenges typical of large-scale IoT systems. Therefore ensuring safe and reliable operations requires careful design. In this paper, we argue that a declarative approach to configuration, complemented with a discovery-driven API design is ideally suited to solve these challenges. We present suitable abstractions needed to realize such a declarative configuration API. Our experiences show that the proposed abstractions and API model are well suited for the purpose of large-scale IoT systems, and allow for high degree of safety and reliability.

Магістерська дисертація складається з пояснювальної записки та графічної частини. Пояснювальна записка виконана на 122 сторінках формату А4, яка включає в себе 29 рисунків, 36 таблиць, 21 джерел використаної літератури. Графічна частина містить 7 аркушів технічних креслень форматом А1. В магістерській дисертації проведено аналіз технічного стану повітряних та кабельних електричних мереж різних класів напруги. Розглянуто реконструкцію лінії електропередавання напругою 110 кВ. Переріз екрану та жили задовольняють вимоги по термічній стійкості. Для схеми ділянки КЛ розраховано зусилля натягу та радіального тиску. Наведено основні обладнання для прокладання кабелю. Проведено дослідження теплових процесів кабельної лінії, які виникають внаслідок протікання струму, за допомогою програми Comsol. Master’s thesis consists of an explanatory note and graphical part. The explanatory note is made up of 122 pages of A4 format; it includes 29 figures, 36 tables, 21 references. The graphical part contains 7 sheets of A1 format technical drawings. In the master's dissertation the analysis of a technical condition of air and cable electric networks of various classes of pressure is carried out. Reconstruction of the 110 kV power transmission line is considered. The cross section of the screen and the cores meet the requirements for thermal stability. Tension and radial pressure forces are calculated for the circuit section diagram. The main equipment for cable laying is given. The study of thermal processes of the cable line, which occur due to the flow of current, using the program Comsol.

Магістерська дисертація складається з пояснювальної записки та графічної частини. Пояснювальна записка виконана на 95 сторінках формату А4, яка включає в себе 25 рисунків, 21 таблиць, 13 джерел використаної літератури. Графічна частина містить 7 аркушів технічних креслень форматом А1. В магістерській дисертації досліджена передача постійного струму, проведений розрахунок усталеного режиму вставки постійного струму між двома несинхронними енергосистемами. Проведено дослідження впливу збурень на стійкість та надійність передачі, за допомогою програми Power Factory. Спроєктовано електричну лінію постійного струму 500 кВ. Визначили та обчислили релейний захист трансформатора ТДТН-25000/110. Розроблено стартаппроєкт. Master’s thesis consists of an explanatory note and graphical part. The explanatory note is made up of 95 pages of A4 format; it includes 25 figures, 21 tables, 13 references. The graphical part contains 7 sheets of A1 format technical drawings. In the master's dissertation the transfer of direct current is investigated, the calculation of the steady-state mode of insertion of direct current between two asynchronous power systems is carried out. A study of the impact of perturbations on the stability and reliability of transmission, using the program Power Factory. A 500 kV DC power line has been designed. The relay protection of the TDTN-25000/110 transformer was determined and calculated. A startup project has been developed.

The transition toward more renewable-based energy systems increases the need for new flexible resources, such as demand response (DR). Previous literature has found various barriers for DR utilization, but much of this research has focused on the initiation of DR operations or barriers in national markets and not on factors that hinder market upscaling and firm internationalization. We address this gap by analyzing interviews with 22 DR companies active in Finland, one of the early mover countries for automated DR. While most of previous research has focused on electricity DR, our interviewees also include district heating DR companies. By using the Technological Innovation System (TIS) framework, we study how the advanced regulatory and market framework and the technology rollout in Finland have affected the DR service development and the internationalization of Finnish companies. Based on our results, the DR market formation in Finland has largely relied on the Finnish transmission system operator's early decision to allow independent aggregation and the early large-scale rollout of smart meters. The advanced home market has enabled firms to develop new solutions and prove their concept. Yet, the highly structured nature of energy markets complicates the access to both advanced and less advanced foreign markets. Highlights • We study how home market affects demand response (DR) business development. • We analyze impacts of advanced home market on internationalization of DR companies. • Advanced market has enabled firms to develop new solutions and prove their concept. • Services developed for an advanced home market do not guarantee export benefits.

Electricity demand presents a repetitive pattern following daily, weekly and seasonal patterns. However, factors like temperature or social events tend to disrupt these patterns introducing outlying data that is difficult to forecast. This paper introduces a new methodology to classify special days without any prior knowledge of the database. Simple classification of special days into two or three categories is insufficient as the consumers’ behavior has many shades on these days. However, classifying special days in a wide range of categories required a deep understanding of the consumers’ behavior on different days and periods of the year. The methodology proposed describes an algorithm to automate this classification starting from a simple day-of-the-week classification and branching into as many categories as needed to fit a real database. Categories with similar profiles are merged to avoid overfitting and actual outliers are detected to ensure that no false categories are created. The methodology is developed using data from 2010 to 2017 and tested in three different systems. The benchmark used is the classification used by the Transmission System Operator in Spain and the test show that the proposed methodology provides more accurate results without the need of an expert to develop the classification.

Electricity distribution prices have steeply increased in Finland since 2015. This research investigates the returns from the Finnish low-voltage electricity distribution business and compares them to returns from three European industry indices. The within-industry distribution of returns is also studied. The Finnish rate of return regulation model used is presented together with the level of allowed returns by the model, four changes to the model are proposed, and the effect of the four proposed changes on the returns allowed by the model are investigated. The results show that the returns of the Finnish DSOs are very high absolutely and comparatively. There is a ca. ten percent segment of the industry that is not very profitable, while ninety percent of the Finnish DSOs have high or very high returns. The proposed changes to the regulation model are shown to have a remarkable effect on the return level. A change limiting the return for equity only would bring down the return to a level that can typically be expected of a return from a natural monopoly company. The results are relevant to the ongoing process of legal and regulatory changes taking place in Finland and for decision-makers and regulators everywhere.