With the increasing share of electric vehicles (EVs), numerous issues arise for the power sector regarding grid integration:

• Integrating EVs into grids: Hosting capacity of distribution networks and optimal locations for (rapid) charging stations?
• Alternatives to grid expansion: buffer storage and controlled charging?
• System serving and cost-efficient use of EVs with minimum user restrictions: Self-consumption optimization, vehicle to grid (V2G)?
• Bundling of EVs and communication with grid operator?
• Grid connection rules (grid codes): Which rules and intervention options should apply? How to prove the compliance of an EV with effective rules?

Different questions are relevant for different actors and there are different approaches to solve them:
»For grid operators
»For manufacturers
»For regulators
»For EV fleet operators

For grid operators:

Distribution grid operators in particular are the first to be affected by the increasing number of EVs. With many EVs in the low-voltage grid, there is a risk of grid overload if a large proportion of the cars are charging at the same time. The number of electric cars at risk of overloading the grid can be calculated with an analysis of the hosting capacity. Assuming simultaneity factors for EV charging, Energynautics can provide appropriate analyses. For grid simulations, we typically use DIgSILENT PowerFactory and also link our models to GIS data so you can see exactly where which elements are overloaded.

We will be happy to advise you on possible remedial measures such as grid expansion or possibilities to intervene in charging, which will become more important in the future due to §14a of the EnWG (in Germany). Interventions in controllable consumers should be non-discriminatory, safe and with minimal user restriction. To ensure this, the interventions should be as automated as possible by a smart algorithm. In previous projects, Energynautics has already implemented various algorithms for this application. Together with you, we will find the best solution for your network, taking into account both technical and economic aspects!

Other challenges arise when planning new, public charging stations. Very large capacities are required, especially at rapid charging stations (e.g., on highways). It must be kept in mind that electrification is not limited to passenger cars, but that trucks will also increasingly drive electrically in the future. Charging capacities in the megawatt range can be expected for freight traffic. A future-proof network must therefore be capable of providing such charging capacities. We support you in the search for suitable locations, in checking the suitability of a grid connection point and in innovative solutions, such as buffer batteries!

For manufacturers:

The use of the flexibility of EVs is increasingly being discussed in the energy industry. The focus is also on bidirectional charging (vehicle-to-grid, V2G) and the first manufacturers are equipping their vehicles with this functionality. However, local grid connection guidelines must be considered when using bidirectional charging. Although the grid codes of the European countries are harmonized by the RfG (Requirements for Generators), they differ in details and especially in the proof of compliance. In Germany, for example, the same requirements apply to cars with V2G function as to stationary battery storages. This includes, for example, requirements for harmonics, fault ride-through capability (FRT), reactive power, and more. Compliance with the Grid Code is verified by measurements and manufacturer declarations and recorded in a unit certificate. Certificates can only be issued by accredited certification institutes.

We will be happy to advise you on the country-specific requirements for V2G or vehicle charging in general, as well as on the necessary proof of compliance.

For regulators:

For some time now, grid connection rules around the world have been changing to reflect the new reality with more and more variable renewable generators connected in a decentralized manner via converters. In recent years, the topic of grid integration of electromobility has also become increasingly important. Here, a variety of questions arise from different areas:

• Which charging plugs should be used?
• How should grid operators communicate with charging EVs?
• What rules apply to bidirectional charging?
• What functionality is needed to not jeopardize safe and stable grid operation, e.g., response to frequency deviations, FRT capability, requirements for harmonics and unbalances, etc.?
• How will grid code compliance be demonstrated?
• What tariffs, billing models and electricity meters make sense?

We can help you revise your grid code and determine appropriate guidelines for your country.

For EV fleet operators:

Electrification of vehicles does not only concern personalized mobility, but also fleets in particular, e.g. the vehicles of logistics and bus companies. The challenge in fleet electrification is that most vehicles are on the road during the day and only return to the depot or logistics center in the evening and are then charged at the same time. This can easily lead to grid connection point overloads and even grid congestion.

In situations where a truck is only in one place for a short time, e.g. for unloading cargo, but the battery still needs to be charged as fully as possible during this time, the high charging power required is the biggest challenge.

In addition to expensive and lengthy grid expansion, innovative solutions are available, such as buffer batteries, smart controlled charging of EVs or a combination of several solutions. We provide you with neutral and manufacturer-independent advice in order to find the technically and economically optimal solution for your fleet or your business together with you!

Your challenge or project idea is not included? Contact us and we will find an individual solution for your questions!