unIT-e² – living lab for integrated e-mobility

Project Structure

At the heart of the unIT-e² project are 4 Germany-wide field trials, the so-called “Clusters”. Supported by the FfE, the partners developed within the Clusters different Use Cases that will be implemented in field trials during the project. The implementation will take place in the urban areas of Munich and Düsseldorf (cit-E-Life) as well as in rural areas of eastern Bavaria (sun-E), Lower Saxony (Harmon-E) and northern Hesse (Heav-E). The Clusters will be accompanied throughout the entire project by the academic research efforts of the FfE and other research institutes, in the context of the Subproject “Research”. Within the Subproject “Grid” instead, the partners bring forward new concepts and components for the successful integration of the electric vehicles into the energy system. Each Subproject and Cluster is briefly presented in the following section. Thorough descriptions of their activities as of December 2023 can be found within the unIT-e² Operations Report (DE).

Harmon-E

Within the Harmon-E Cluster, the whole process chain is developed and demonstrated, from the markets for electricity and ancillary services all the way to the flexible (dis)charging of electric vehicles. The goal is to achieve an interaction of the overall energy and grid management system that works seamlessly for the users. Since all the field tests to this aim are in progress, some first preliminary results are already available. In the Harmon-E Cluster the focus is on a charging concept for electric vehicles that is at the same time optimal for the market and supportive of the grid and the system. In total, six different Use Cases are developed, tested and showcased in the context of three field tests. These field tests differ in terms of the geographical location, the inclusion of various flexibility aspects, and the differently prioritized implementation of the Use Cases. Additionally, the Use Cases are tested in a laboratory environment not only for unidirectional applications, but also for bidirectional cases.

Heav-E

The Heav-E Cluster is embedded in northern Hesse and focuses on the charging behavior of users, in the context of a field trial with the participation of several regional partners. Next to the analysis of the status quo of the grid load due to electromobility (how vehicles are charged today), the main focal point is on investigating how the load peaks due to charging can be shifted with the help of targeted incentives for the users. The field test in Cluster Heav-E started in July 2023 with a test group of 68 people that are able to charge their vehicle at their place of residence. The acquisition of test participants and their coordination are managed by the Regionalmanagement Nordhessen GmbH. The field test is carried out with the participation of EAM Netz GmbH, Flavia IT-Management GmbH, the University of Kassel and Volkswagen AG.

sun-E

The sun-E Cluster set itself the goal of investigating unidirectional smart charging solutions with a focus on private homes. To this aim, the companies Bayernwerk, Lechwerke, TenneT, PPC, Kostal, EEBus, Consolinno, and BMW work on the technical and operational implementation of the Use Cases, supported with scientific research from the Forschungstelle für Energiewirtschaft (FfE) and the University of Passau. The test field, with 20 planned pilot vehicles, covers the entire grid area managed by Bayernwerk and thus a large part of Bavaria’s surface.

Cit-E-Life

The Cit-E-Life Cluster is characterized by a diverse network of partners. Participants of this network are the “Stadtwerken” (municipal utilities companies) of Munich and Düsseldorf, the TSO TenneT as well as the component manufacturers Consolinno and PPC, the EEBus Initiative, the FfE, and international OEMs like Ford and Schneider Electric. The broad base of this Cluster allows different perspectives on the challenges and possible technical solutions for the integration of electric vehicles into the existing power supply systems. In the second quarter of 2023 two more partners were welcomed to the Cluster: the metering point operator Thüringer Mess- und Zählerwesen Service GmbH (TMZ) overtakes a central role in the field tests, and the cooperation of Stadtwerke under the Trianel GmbH makes use of its network to incorporate the feedback of small and medium-sized municipal utilities into the solutions developed in the project.

SP Grid 

Within the Subproject „Grid“, procedural and technical solutions for the integration of electric vehicles into the energy system are elaborated by the energy industry partners. This lays the groundwork for the hardware and software components utilized in the real-world tests, as well as for the control and regulation strategies. For the integration of decentralized small-scale flexibilities into the electricity grid, the project also investigates the points of interaction among the respective stakeholders, the process towards the provision of ancillary services and the development of grid-supporting coordination mechanisms. Here a close exchange with the FfE activities within the Subproject “Research” takes place, on one hand to bring scientific evidence into the discussion, and on the other hand to challenge these academic results together with the partners from the practical side. One goal of the Subproject Grid is, among others, to derive basic recommendations for action for the policy makers and the standardization organizations, to reach the overall goal of interoperability between the energy system and the automotive industry.

SP Research

The scientific support to the project is provided entirely by the FfE together with other universities and research institutes. This gives the four real-world laboratories a stable scientific foundation. The FfE focuses in particular on the study of energy systems and distribution grids, on the development of approaches for future grid management and on the academic support of the field trials. The obtained results are synthesized together with the practical findings from the monitoring of the Clusters and of the SP Grid, in order to formulate the relevant options for action from a research perspective.

In the following sections, the five areas of interoperability, distribution grids, forecast and commercialization, KOALA, and energy system are described in more detail.

Interoperability

Within the unIT-e² project, interoperable solutions are developed for every step of the operating chain, which is why partners from all industries that interact with electromobility are involved: automotive industry, Smart-Meter-Gateways (SMGW) manufacturers, grid operators, energy suppliers, charging infrastructure manufacturers, aggregators, software developers, charging station operators, and academic researchers. The creation of interoperable solutions without “Lock-Ins” or “Walled Gardens” opens the door to a competition of ideas and services that represents a fundamental basis for a successful ramp-up of the electromobility market. For Germany to remain a central location of the automotive industry within the international context, interoperability and a goal-oriented standardization are of paramount importance at the industrial and the political level. The goal of the System Architecture working group is to develop a contribution from the unIT-e² consortium by investigating the connections among different agents and systems, and working out an overall architecture across all clusters.

To this aim, the group relies on the previously developed system architectures of the four clusters and develops in a three-phase process a new, all-encompassing architecture. The focus would then be on the Use Cases tested within the field trials. To ensure the interoperability among different Clusters’ solutions, a two-day “Plug fest” is held. The main goal of this event is to demonstrate the interoperability solutions among Clusters through comprehensive interoperability tests. The results of these tests not only allow to evaluate and improve the interoperability of the overall unIT-e² system, but also offer valuable insights into the quality of the employed standards and norms, and the possible need for further developments in this area.

Publications:

• Interactive System Architecture of the Harmon-E Cluster
• From Electromobility Use Cases to an Interactive System Architecture: the Harmon-E SysArc in the unIT-e² Project 

Distribution grids

As part of the studies on the integration of bidirectional electric vehicles into the energy system, the FfE addresses research questions about the true intersection point of the energy system: the distribution grid.  Simulations are used to analyze whether and how the distribution grids, in particular at the low voltage level, can withstand the increase in flexible consumers under different conditions. The analysis of the interplay between distribution grids and electromobility is done within the project through the framework of four key research areas:

1. Simulation of grid-supporting and market-oriented Use Cases for bidirectional electric vehicles
2. Assessment of the representativeness of characteristic distribution grid topologies for real grids
3. Analysis of grid limits in terms of the maximum amount of integrable electric vehicles
4. Evaluation of the resulting need for grid expansion

The implementation of Use Cases simulations is done in order to analyze the effects on the grid load of different market-oriented and grid-supporting operating strategies for flexibility. Additionally, research is conducted on whether the topological diversity of German distribution grids can be modeled and categorized into typical grid structures, and on how accurately these reproduce the real topologies. Grid limit analyses are used to determine the maximum capacity limits of the current distribution grids at different sensitivity levels, in order to derive some reference values for the planning of grid expansions. The need for grid expansion due to the integration of numerous new electricity consumers is also analyzed.

Publications:

• Series of articles on the characterisation of low-voltage grids (EN)
• In progress: „Case study: dynamic pricing vs. bidirectional charging” (DE)

Forecasts and commercialization

In the area of forecasting and commercialization we find the following three key elements:

• Forecasts
• The added value of smart charging strategies from the user’s perspective
• The repercussions of user behavior on the power system

Forecasts

As part of unIT-e², different methods for the forecasting of variables relevant to the energy system were examined, as well as how time series can be characterized in general. There are several metrics to evaluate and compare forecasting models. A selection of models and different metrics, as well as an example including code, are described in three articles on the Website linked under “Publications” below. For the Use Cases of electromobility, particularly interesting is the prediction of short-term charging behavior of electric vehicles (especially plugging and unplugging time as well as energy consumption). For this purpose, the FfE is developing the predictive model EVision, which serves as the basis to determine the available flexibility of charging processes and their commercialization. In this case the focus lays on the forecasting of parking duration, energy consumption, and the combination of the two at company locations and for private customers, based on real data. On top of this, the FfE developed a model for the short-term forecasting of the German CO2 emission factors. The method and results are described in the linked Publication (EN). The goal is to transfer within unIT-e² the application-related models into a generic model. Further publications on the topic are in preparation for 2024 and will be added below as soon as they are released.

Publications

• Predictions in Energy Economics – Which Error Metrics Are Suitable? (EN)
• Predictions in Energy Economics – Which Methods Are Suitable? (EN)
• Predictions in Energy Economics – Tutorial on Household and PV Load Forecasting (EN)
• Short-term forecasting of German generation-based CO2 emission factors using parametric and non-parametric time series models (EN)
• In progress: “EV Energy Forecast and Energy Procurement”

The added value of smart charging solutions from the user perspective

Here, the costs, revenues and resulting profits for agents and customers are analyzed for different Use Cases from the Clusters and within unIT-e². To determine additional benefits for the customers, not only individual Use Cases are considered, but also a combination of multiple ones. The revenues are determined with eFlame (agent-based model to evaluate flexibility in the energy system – DE). For this, a combination of multiple Use Cases is implemented, allowing gradual commercialization on several spot markets as well as the combination of time-based arbitrage / tariff-optimized charging and PV self-consumption optimization. Considering the relevant Use Cases and combinations thereof, realistic scenarios (for today and 2030) are modeled to evaluate the economic efficiency and the operation-related emissions of smart charging strategies. Aside from the possible monetary value, it is also relevant for the customers to know how big the potential of a Use Case is – for instance, whether saturation would be reached quickly, so that entering the market is only worth it as a First Mover. Considering a possible overloading of the distribution grids due to the rapid scaling of electromobility (see also the section about distribution grids simulations), the DSOs have the possibility of “dimming” (§14a Law on Energy Economics – “EnWG”) in case of emergency. The effect that dimming would have on the customers’ use cases is also taken into account, to determine as realistically as possible the possible added value of the different Use Cases.

Publications 

• Synergies of Electric Vehicle Multi-Use: Analyzing the Implementation Effort for Use Case Combinations in Smart E-Mobility (EN)
• Smart e-mobility: User potential in Germany today and in the future (EN)

Repercussions of user behavior on the energy system

The influence of market design on revenues

To determine the potential of the market-oriented Use Cases, as well as the revenues on different marketplaces, an analysis of the markets (national and international) is necessary. This includes the mid- and long-term developments at the electricity exchanges, short-term price developments especially on the Intraday markethttps://www.ffe.de/en/publications/intraday-price-forecast/, and also the markets for ancillary services, for instance for the balancing energy market. Also considered are potential changes in the market design, as they are for instance currently discussed in Germany for capacity mechanisms.

Influence of agent-side Use Cases on the energy system – e.g. PV self-consumption optimization

The economic analysis of smart electromobility Use Cases for customers is often approached from the customers’ perspective. However, this also influences the energy system as a whole, which in turn can result in changes for the customers. Accordingly, this interdependency is analyzed in unIT-e² for the Use Case of PV self-consumption optimization with electric vehicles.

Publications

• IEWT 2023 at TU Vienna (EN)
• Marketing of Small-scale Assets in Germany (EN)
• Comparison of European electricity market designs (EN)
• The European balancing energy market (EN)
• What is the balancing energy market (RAM)? (DE)
• How does the Merit Order work? (EN)
• Merit order shifts and their impact on the electricity price (EN)
• Intraday price forecast – FfE (EN)

KOALA: Coordination and allocation algorithm

An emergency mechanism as defined in the current version of the § 14a EnWG by the Federal Networks Agency (Bundesnetzagentur) is designed to stabilize the grid in the short term, but it doesn’t consider any opportunity costs on the side of the connection user nor does it take on a coordination role, thus accepting the possibility of an inefficient allocation. Because of this, within the unIT-e² project a market-based coordination and allocation algorithm is developed, to be used as voluntary and complementary Add-On for the decisions of the Networks Agency (BNetzA).

The core of the mechanism is based on the idea that the limited grid capacity in case of a bottleneck situation is distributed as needed, or rather allocated, among all affected asset operators (e.g. within the same low-voltage line) through an auction system. This also explains the project acronym: “Koordinations- und Allokationsalgorithmus“ (Coordination and Allocation Algorithm) for flexibility. In a bottleneck situation, the auction leads to the creation of a scarcity price, that reflects the state of the grid with a mechanism similar to that of dynamic grid fees. However, the price is not determined by the grid operator, but it is rather the direct “bottom up” result of the bids and thus of the opportunity costs of the asset operators. Even in the case of a bottleneck, a predetermined basic contingent, for instance of 4.2 kW per controllable consumer unit (“SteuVE”), remains reserved and is not included in the auction.

The concept also reflects the fact that within the framework of § 14a EnWG the provision of flexibility through controllable consumption devices is generally rewarded with a “stability premium” in the form of reduced grid fees. On top of this, it would be possible to distribute the total auction proceeds among KOALA participants equally, to add a financial incentive to the mechanism. This means that particularly flexible asset operators that shift their power consumption to times without congestion are additionally remunerated. Less flexible connected users, instead, gain through the auctions a tool to reduce control interventions by the grid operator in case of need, but they may need to pay a high scarcity price for this.

The KOALA mechanism, with its auction mechanism, also creates new possibilities for preventive congestion management. The initial plan is that the system operator, based on their Day-Ahead forecasts, is able to issue a congestion warning to give asset operators the possibility to adjust their plans on time. During the announced bottleneck timeframe, capacity auctions would be initiated sequentially for the following 15-minute timeslots. This would minimize forecasting uncertainties, while at the same time allowing participants to bid for their urgent power requirements. Because each bid is linked to willingness to pay, the warning gains more relevance than a pure load forecast.

Publications

• Bridging the Gap between Electric Mobility and the Power Grid: A Novel Mechanism to Tap the Grid Serving Potential of Flexible Assets (EN)
• In progress: „The unIT-e² KOALA – An incentive based mechanism for the coordination of grid-supporting control operations” (DE)
• In progress: „White paper – Grid fees system” (DE)

Energy system

In this area, a future vision for the energy industry is developed. The simulation of the future energy system is realized with the ISAaR tool and it includes the energy market as well as its repercussions on the transmission system. The visualization is realized with ISAaR-Charts, an interactive dashboard based on Plotly Dash.

Scenarios and model extensions:

The base scenario for Europe is developed in 5-year increments from 2025 to 2045. Sensitivities in the context of integrating electric vehicles into the European energy system are also analyzed. These sensitivities are for instance new technologies, such as second life battery storage as competition to smart electromobility, or Use Cases, such as PV self-consumption optimization through electric vehicles.

Repercussions on the transmission grid:

Grid calculations are also carried out to determine the grid loading. These then lead to required redispatch quantities, and allow to investigate alternative market designs, like nodal pricing, and their effects on the energy system. Additionally, the grid model is extended to include overhead power line monitoring.

Repercussions on the energy system:

Thanks to market calculations, for a given scenario it’s possible to determine the status of the European energy system, including generated emissions and resulting costs.

Environmental effects:

In the context of a meta study, the ecological break-even point of electrical and combustion vehicles was examined (https://www.ffe.de/veroeffentlichungen/welche-parameter-beeinflussen-die-oekobilanz-von-elektrofahrzeugen/ – DE). The decisive factor for this is especially the electricity mix used by the electric vehicle in its operational phase. Within the project, not only the emissions at the vehicle level were analyzed, but also the repercussions of different Use Cases on the whole system, which includes the emission factors of electricity generation.

Publications: 

• Welche Parameter beeinflussen die Ökobilanz von Elektrofahrzeugen? (DE)
• Overcoming challenges in life cycle assessment of smart energy systems – A map of solution approaches (EN)
• Assessing Environmental Effects of ICT in Smart Energy Systems – Case of Bidirectional Charging (EN)

Results of the whole project

After the project’s first year, several challenges were identified and specified, which are addressed as the project continues. Additionally, a need for legal or political adjustments was also identified in various areas. These findings (as of November 2022) for different thematic areas of the project are compactly illustrated and described in the unIT-e² Work-in-Progress Report 2022 (DE). As living laboratory, the project places a particular focus on the practical implementation and testing within different field trials of the developed solutions for the optimal integration of electromobility into the energy system. These are then presented and discussed by topic in this Operations Report (DE) (as of December 2023). This unIT-e² Operations Report is the second comprehensive interim documentation after about two years of the project, following the Work-in-Progress Report (DE) published after the first year. In addition to the field tests, interim results from the accompanying scientific and legal analyses are presented, and options for action are derived with regard to the political and regulatory frameworks.

A joint FfE project

Thanks to the cooperation of the FfE with additional partners from the energy industry, more companies are involved in this research project. These “cooperation partners” gain, among other things, the opportunity for direct contact and exchange with the partners implementing the project. Additionally, regular workshops allow for a comprehensive transfer of knowledge from and within the project. The following partners support the research efforts of the FfE, both financially and with data from individual, practical experiences:

• Energielösung4all GmbH
• ENERVIE Vernetzt GmbH
• Illwerke vkw AG
• N-ERGIE Netz GmbH
• Netze BW GmbH
• Stadtwerke Rosenheim Netze GmbH
• TEN Thüringer Energienetze GmbH & Co. KG
• Trianel GmbH
• TransnetBW GmbH
• Voralberger Energienetze GmbH

Funding

The research project is financed by the German Federal Ministry for Economic Affairs and Climate Action (Bundesministerium für Wirtschaft und Klimaschutz – BMWK, Project ID: 01MV21UN11 FfE e.V., 01MV21UN01 FfE GmbH). The sponsor / responsible body for the 3-year joint project is the German Aerospace Center (Deutsches Zentrum für Luft- und Raumfahrt – DLR).

Further information:

• Project unIT-e² Website (EN)
• unIT-e² E-Mobility & Grid Talks (DE)
• Save the Date: 11. Juli 2024 – Berlin! (DE)