Brief overview
- Definition: A VINK is a network component that is firmly integrated into the transmission or distribution network and serves solely for the safe and reliable operation of the network. It is not used for regulating power or for congestion management.
- Why the term is important: Network operators are generally not allowed to own or operate energy storage systems (unbundling). The VINK is one of the two legal exceptions.
- Battery storage: According to the current practice of the Federal Network Agency (BNetzA), battery storage systems cannot be VINKs.
- Power Booster: A network booster serves to relieve network congestion and is therefore not a VINK.
Anyone who deals with battery storage systems and grid operators sooner or later comes across the abbreviation VINK. It appears in legislative texts, in grid development plans, and recently also in studies on the expansion of the distribution grid, often with different meanings. This article explains what a fully integrated grid component is, why it is associated with the separation of the grid and the market, and how it differs from the grid booster.
What is referred to as a VINK?
VINK is the abbreviation for „fully integrated network component“. The term originates from European law (the Electricity Market Directive (EU) 2019/944) and was incorporated into the Energy Act (EnWG). The Federal Network Agency describes a VINK as a network component that is integrated into the transmission or distribution network, including energy storage systems, and serves solely to maintain the safe and reliable operation of the network.
Three characteristics are crucial:
- Integration into the network: The component is part of the network infrastructure, not a separate market participant.
- Exclusive network purpose: It serves solely to ensure network security and reliability, such as maintaining voltage levels or providing reactive power.
- No market function: It is not intended to be used for providing Balancing energy and not used for bottleneck management.
The BNetzA cites capacitors and flywheel or flywheel-mass storage as typical examples. These devices stabilize the grid without trading electricity on the market.
In practice, network operators VINK primarily use it for system services such as Reactive power and Inertia (instantaneous reserve) One. Basically, each network operator is responsible for covering its peak power demand on its own, and can rely on its own reserves to do so. Transmission system operator VINK increasingly sees this as a fallback level: If the market does not provide a system service at reasonable costs, the network operator can provide it itself. This also sets a price cap for market procurement.
Why are VINKs being introduced? Unbundling for network operators
Anyone who wants to understand VINK should know about unbundling.
What does unbundling mean?
Unbundling (decoupling) refers to the legal and organizational separation of network operation from generation, trading, and distribution. The goal is to achieve a non-discriminatory access to the network. A network operator should not have an incentive to favor its own market activities over those of competitors. In Germany, the de-coupling is regulated in §§ 6 ff. of the EnWG.
Why does this affect the energy storage?
A Battery storage It buys and sells electricity. It is therefore a market participant, not just an infrastructure operator. The BNetzA therefore makes it clear: Energy storage systems in principle may not be owned, built, managed or operated by network operators. This contradicts the provisions of the Deregulation Act. Juridically speaking, this constitutes a preventive ban with a permission requirement.
The two exceptions under § 11b EnWG
The BNetzA may only grant permission to a network operator to own an energy storage system in two cases:
| Gone | Prerequisite | Is market testing necessary? |
| Approval after unsuccessful market test | The network operator points to the energy economic necessity, excludes a market use of the storage and has previously unsuccessfully tendered for it (§ 11a EnWG) | Yes |
| Approval of a VINK | The system is a fully integrated network component | No |
The VINK is thus the special route without a market test. This is only logical: A component that serves solely for network security and does not participate in the market does not distort competition. A network operator that wants to have the VINK approved must technically and legally explain to the BNetzA why the planned installation is a VINK.
The normal case: tender under § 11a EnWG
For storage facilities that are not VINKs, the law provides for an invitation to tender. Network operators may tender the construction, operation and management of an energy storage system as a service if they can prove that the system is necessary to fulfill their legal obligations. The owner of the storage facility remains a third party; the network operator only purchases the service. Market-based procedures for procuring system services (tenders) take precedence in this context.
VINK and Net Booster: the difference
Both terms are often confused because they appear in the context of network operators and storage providers. However, they denote different things.
A Network booster is a concept developed by transmission grid operators to relieve grid congestion. Large storage units at network nodes are designed to take or release power in a short time in the event of a disruption, thereby reducing redispatching and grid expansion. We explain how network boosters and system boosters work in our article. Power supply boosters and system boosters.
One VINK On the other hand, it is a legal category. It describes which network components a network operator may exceptionally own themselves, and it explicitly excludes congestion management.
| VINK | Network booster | |
| Type of term | Legal category (disintegration law) | Technically-conceptual approach of the transmission grid operators |
| Purpose | Maintaining safe and reliable network operation (e.g., reactive power, voltage control) | Reductions in network congestion, reduction of redispatching and network expansion |
| Bottleneck management | Exclusively excluded | Core function |
| Typical technique | Capacitors, flywheel energy storage | Large battery storage |
| Is battery storage possible? | According to BNetzA practice: no | Yes |
The logic behind it is simple. A storage system that manages bottlenecks intervenes in market processes. That is precisely why it does not fall under the VINK exemption. The network booster is therefore none VINK, even though both components serve the network.
Why the term is often taken too far
The term VINK is not used in a legal sense everywhere. A current example is the study „Cost-efficient expansion of the distribution network“, which Agora Energiewende published together with the Research Center for the Energy Industry (FfE) and Consentec at the end of October 2026. The study concludes that the Expansion costs the distribution networks by 2045 of around 250 billion euros to reduce by about 66 billion euros Let network operators include more flexibility in planning and operation.
In this context, the authors also examine „grid-scale storage (VINK)“ as one of several measures. These are battery storage systems that are specifically deployed by the grid operator to relieve individual bottlenecks. The study classifies them as a temporary solution for networks with few, clearly localized bottlenecks.
Important for the classification: The study is a model calculation for network expansion, not a legal assessment. A battery storage system developed by the network operator to alleviate congestion does not, in accordance with the practice of the BNetzA, meet the legal VINK definition. The BNetzA rejected an application for recognition of battery storage systems as VINK in July 2025 (Decision of the Federal Network AgencyAnyone reading the term in studies, presentations, or tender documents should therefore check whether the legal or colloquial meaning is intended.
What does this mean for battery storage systems and their operators?
For operators of battery storage systems, the VINK regulation is relevant for a particular reason: it ensures that battery storage systems remain on the market.
Network operators cannot operate battery storage systems themselves via the VINK system. If they want to use a storage facility for grid purposes, the path leads through the tender procedure under § 11a EnWG. Third parties, such as private storage operators, can then offer the storage service. This is fundamentally an opportunity for the market, even though tenders for grid services are currently the exception.
Network availability is also possible without VINK. Storage can relieve the burden on the grid without becoming the property of the grid operator. The legislator has created flexible connection agreements (FCA) to enable faster connection of storage even in cases of limited grid capacity, if the operator accepts restrictions in case of congestion. Read more about this in our article. Flexible network connection agreements (FCA). The combination of storage facilities with generation facilities at the common grid interconnection point also relieves the grid, see Co-location of battery storage systems.
For companies planning a battery storage system, a clear guideline emerges: The storage system belongs to the operator and is optimized for the market. The utility-scale effect arises through connection agreements, site selection, and co-location, not through the ownership of the network operator.
FAQ
What does VINK mean?
VINK stands for „fully integrated network component“. This refers to a component that is firmly integrated into the power transmission or distribution network and serves solely for the safe and reliable operation of the network, not for regulating power or for congestion management.
Can a battery storage system be a VINK?
According to the current practice of the Federal Network Agency, no. As examples of VINK, the BNetzA cites capacitors and flywheel energy storage systems. It rejected an application for recognition of a battery storage system as a VINK in July 2025.
Why are network operators allowed to own VINK, but other storage providers are not?
Because a VINK is exclusively intended for grid operation and does not participate in the electricity market. It does not distort competition and therefore does not contradict the idea of unbundling. The ownership ban applies to all other storage facilities; the BNetzA only grants exceptions after a failed market test.
Is a network booster a VINK?
No. A network booster serves to relieve congestion in the network. However, congestion management is explicitly excluded from the VINK definition. VINK is a legal category; network booster is a technical concept developed by transmission grid operators.
Sources
- Federal Network Agency: FAQ on §§ 11a and 11b of the EnWG (energy storage systems by network operators)
- Agora Energiewende, FfE, Consentec (2026): Cost-efficient expansion of the distribution network. A step ahead of the expansion contractors
- Nettransparenz.de: Guide to the operational efficiency of network operators (2024)
- Amprion: Concept paper for the system market
