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This research developed an application for electrical vehicles charging stations (EVCS) to estimate the optimum day-ahead bidding profiles in frequency containment reserves (FCR) markets and this paper presents the stochastic methodology behind this application. To achieve this, first, deterministic models are developed to calculate the maximum FCR that could be provided by each charging event (cycle) of an electric vehicle (EV). These models are established based on the technical requirements of FCR in the Nordic flexibility market, namely the frequency containment reserve for normal operation (FCR-N) and frequency containment reserve for disturbances (FCR-D). In the next step, these deterministic models will be combined with historical data of charging records in EVCS to calculate the probability density functions of the FCR profiles. Finally, the proposed application estimates the optimum FCR profiles, which maximise the expected profit of EVCS from participating in the day-ahead flexibility market, by performing a stochastic optimisation. The performance of the proposed application is evaluated by using empirical charging data of public EVCS in Helsinki area.

This deliverable describes the work conducted in ERIGrid 2.0 task NA4.1 ’Definition of Functional Scenarios’. The work has been conducted via a survey and a brainstorming workshop. The results are six Functional Scenarios:1. Ancillary services provided by Distributed Energy Resources (DERs) and active grid assets,2. Microgrids & energy communities,3. Sector coupling,4. Frequency and voltage stability in inverter dominated power systems,5. Aggregation and flexibility management, and6. Digitalisation,which describe the overarching topics within ERIGrid 2.0. The Functional Scenarios will be used as an input in further ERIGrid 2.0 work. Smart grid and smart energy systems solutions have become complex and multidisciplinary. With the further integration of Information and Communication Technology (ICT) and other energy systems new testing scenarios, profiles, and processes must be defined. In order to achieve this, big trends affecting research, testing, and validation processes have been reviewed, with a special focus on new aspects such as interoperability testing or digitalisation. The scenario descriptions define requirements, actors, etc. on a functional level. ERIGrid 2.0 work package NA4 ’Iterative Creation of Scenarios and Test Case Profiles’ addresses these needs. This work has been conducted with emphasis on the alignment with the European Green Deal, further support on the technology validation and roll-out phases, and further integration of the research infrastructures. A Functional Scenario has been defined as an umbrella term comprising of motivation and relevance for ERIGrid 2.0, system descriptions, use case and test case descriptions, and experimental setup descriptions. Each scenario has a single core idea and is formed on the basis of inclusiveness. Functional Scenarios consider several high-level scenarios in other projects and networks as a background forming the overall circumstances in which the Functional Scenario is considered. The high-level scenarios provide a holistic understanding of the current status and development while also highlighting future visions and requirements impacting the Functional Scenarios. The high-level scenarios also address the high-level drivers for the Functional Scenarios, such as needs for digitalisation of the smart energy systems. Furthermore, Functional Scenarios are related to the generic system configurations developed in ERIGrid and consider the work conducted in ERIGrid as a strong background for ERIGrid 2.0.The necessity for a mutual understanding of scenarios which are of interest to the ERIGrid 2.0 partners and their research infrastructures and in alignment of the project objectives, led to conducting a survey regarding the first actions of the NA4.1 work. The purpose of this survey was to gather inputs on a set of Functional Scenarios that were analysed in more detail to deduce the most relevant approaches for ERIGrid 2.0. Overall, 15 partners participated in the survey and submitted 35 scenarios. The survey results include scenarios on sector coupling, multi-energy systems, ICT and automation, energy communities, microgrids and low-inertia grids, and stability, control and grid code challenges. Detailed descriptions of Functional Scenarios submitted to the survey are presented in Appendix A: Functional Scenario Survey Data of this deliverable.The formation of the Functional Scenarios was organised in six working groups, each of which focused on a single Functional Scenario. The decision on the six Functional Scenario was taken during the NA4 regular meetings and the brainstorming workshop itself based on the results of the Functional Scenario survey.The focus of the first working group has been on a component focused scenario developed based on the survey results on DERs and inverters. The resulting Functional Scenario 1 integrates key components, such as DER inverters and controllers with ICT, control and automation architectures to enable new grid services with the development of interfaces between the active components. The second working group has been focused on topics related to microgrids and energy communities forming Functional Scenario 2 to support the local microgrid and energy community development by enabling flexibility services locally with ICT and control including exploitation of grid intelligence. While the third working group has been working on the survey results on sector coupling and multi-energy systems with Functional Scenario 3 anticipating a massive roll-out of power-to-X components in the near future by developing system level understanding of the impacts on the electrical domain. The fourth working group has been focused on grid management and overall the perspectives of Distribution System Operators (DSOs) and Transmission System Operators (TSOs) resulting in Functional Scenario 4 assuring frequency and voltage stability in low inertia systems through capabilities of Renewable Energy Sources (RES), Distributed Generation (DG), controllable loads and storage systems as well as ICT and control systems. The fifth working group has been based on the survey results comprising of aggregation, flexibility, market and reserve topics and defined Functional Scenario 5 to focus on communication functionality for aggregation, service matching, fail-over, configuration, and interoperability addressing scale-related properties of aggregation and control solutions. Lastly, the sixth working group has been focused on digitalisation including wide range of topics such as ICT infrastructure, communication, automation, control and monitoring. Functional Scenario 6 explores the impact of ICT solutions on the physical (electrical power) system covering new applications of data and data processing as well as new paths for exchanging data.The Functional Scenario templates used during the brainstorming workshop have been included in the Appendix B: Functional Scenario Templates.The work started in NA4.1 will continue in NA4.2 and NA4.4 with discussions on more detailed definitions of the test cases which will initially provide the inputs for other project activities. The discourse on the Functional Scenarios is also assumed to support ERIGrid 2.0 physical lab and virtual access work and decision-making beyond ERIGrid 2.0.

The value of active demand in the electricity and ancillary service markets depends very much on the predictability of its aggregated control responses. In this work, the authors study electrically heated small houses that have electrical heating with heat storage tanks and remote control via a smart metering system. They integrate a simple physically based model to a machine learning forecasting method thus combining the strengths of the component methods. Now a stacked boosters network, a new deep learning method, is applied and briefly compared with a support vector regression, an earlier machine learning model. The simple physically based model component models the thermal dynamics of the heat storage tank and the outdoor dependent heat demand of the house. Varying types of a heuristic market based dynamic load control were applied during the field trials that comprised an identification period (31 May 2012–31 May 2013) and a verification period (1 January 2015–31 December 2019). Each of the 727 houses was hourly metered and aggregated into two groups. The short-term forecast the power of these dynamically controlled groups. They summarise the results. The hybrid method outperformed its component methods.

This Electra internal report includes the work of Task T6.1 describing the nature, availability andcontribution of flexibility resources. This task also models the interactions across controlboundaries and identifies sources of control conflicts, giving also an overview of experiences fromthe ELECTRA partners regarding the realization of controllers in demonstration and field testprojects. The work was carried out during the period from May to December 2014.The different type of flexibility resources, their characteristics, affecting market mechanisms andpotential for aggregation were researched using a survey among project partners. The parametersused to characterise flexibility include the amount of power modulation, the duration, the rate ofchange, the response time, the location, the availability, the controllability, etc. Views were alsoreceived how these parameters will develop until 2030 and what are the general trends fordevelopment of amount and controllability of this resource types. The parameters characterisingdifferent energy resources provide the technical requirements for their applicability to flexibleoperation of the grid and their suitability for frequency and voltage control now and in the future.Regarding the flexibility of electricity generation, gas turbines and other heat motors asreciprocating engines can be started quickest. The speed of power change is clearly the highest forheat motors and their minimum power is low. Also steam and combined heat and power plantscan be utilised in the relatively quick increasing of the electricity generation. Slower power changesare possible also with the nuclear power but they cannot be carried out continuously. Theregulation characteristics of hydro power are superb in comparison to the other electricitygeneration methods. Besides the sun power, wind power is increasing most quickly in the world inthe coming years. The modern wind power plants are able to active and reactive power control.Storage systems can contribute to the frequency and voltage control mechanisms. Charging anddischarging of the storage system at the right moments (response within milli-seconds to seconds)can help to preserve the balance between consumption and generation. Storages can also providesecondary and tertiary frequency control. Static compensation devices maintain desired voltagelevel by feeding the grid with necessary reactive power. FACTS devices and cross-borderconnections based on HVDC converter schemes can play an important role in frequency andvoltage support. Demand response, including industrial loads and household devices and electricvehicles, will have great influence in flexible operation of the grid.This report describes appropriate models that characterize the interactions across controlboundaries under normal and emergency situations, introducing suitable data rates and models ofuse by real-time control functions. In the future power system scheme, TSOs will be able to controlsignificantly smaller part of the generation compared to the traditional centralized configuration,and thus they will not be able any more to compensate large deviations in the power balance.Moreover, increased electricity loads and sources such as EVs and residential PV systems, willinfluence the balance between day-ahead production and consumption schedule and will leaveenergy markets with higher and less predictable need for balancing power. The actors involved inthe future grid control are balance responsible Party (BRP), cell system operator (CSO), celloperational information system (COIS), distribution system operator (DSO). Their respective rolesare described and these actors play roles both to technical and market operations. Considering theweb of cells concept developed in this project, the generation units will be smaller and in manycases these will be renewable resources which are less suitable for frequency control [1]. For thatreason a more important role for participation at the demand side will be expected for voltage andfrequency control in the future. The report describes “model based interfaces”, where the flexibilityuser and the flexibility contributor agree on a simplified model which describes the actual behaviourand constraints of the flexibility resource. Main outcomes of the work are the definition of controller conflict from a flexible power system perspective, a review of state of the art in power system control conflict and an outline of the methodology for identifying these conflicts during system operation and their impact on system stability. The report summaries the main findings from the literature and from project participant’s experience in terms of scenarios or examples of controller interactions resulting in conflict. A measure of controller conflict is presented for each example. This can be used as an indicator of the impact of controller conflict on system stability. Suggestions for resolving controller conflict arealso presented. The report describes the methodology proposed to construct such a dynamicmodel for the purposes of extracting conflicting interactions of interest from the point of viewfrequency and voltage stability. From the voltage stability perspective there are many factors whichmay significantly influence the environment for voltage stability. It seems quite certain, thatpossible conflicts affecting voltage stability may occur mainly due to lack of proper coordinationamong players in the system voltage control and reactive power reserves management which areTSOs, DSOs, Generators and Aggregators. Generally the scenery foreseen for frequency, voltageand reactive power control in 2030+ is much more complicated than it is presently.An overview of experiences from the ELECTRA partners regarding the realization of controllers indemonstration and field test projects are also provided. It summarizes best practices and lessonslearned which will provide valuable inputs for the implementation of control concepts and theirtesting and validation. The main requirements for controllers are reliability, fault tolerance androbustness.

The European ADDRESS project aims at a market based integration of Active Demand (AD) into the power system in order to the provide services to the different power system participants, especially the distribution and transmission system operators. The ADDRESS project focuses mainly on the technical aspects of such AD integration, but additional research was carried out to analyse the existing market mechanisms and the required adaptations and evolutions. The results of this market mechanisms analysis is presented in this paper. The paper browses the existing markets that are relevant for the AD solutions proposed by ADDRESS and addresses the barriers to the integration of AD, mainly the minimum size of a bid or offer and the costs for participating. The actor who gathers AD in order to form products to offer them to the other actors, referred to as the aggregator, would need to collect a large number of consumers' flexibility in order to overcome those obstacles. Two possibilities are presented to facilitate the participation of AD. One is a regulatory change allowing smaller resources to participate. The other one is the creation of a flexibility market pooling the capacities from various flexible resources. The "pay-back" effect, which occurs at the moment that the flexible resources return to their normal state, is an additional risk for the resource operator. The paper proposes a new bid type including both the flexibility and its "pay-back" effect. The paper presents existing mechanisms to deal with grid constraints at the transmission level, such as capacity auctions and the re-dispatching in case of other network problems. Possibilities for the distribution system operator (DSO) to adapt them to the distribution level are proposed. The DSO could set up bilateral contracts, calls for tenders or an open market to deal with local constraints. Bilateral contracts would be the first option; other potential solutions could become available as the amount of local resources increases. In cases where these market based mechanisms are not sufficient, the DSO may need to curtail the use of some resources, particularly the flexible ones. The paper proposes a simple curtailment, without any form of compensation for the owners of resources and a redispatching option inspired from the transmission system level.