From "First Come" To "First Ready": Germany's New Maturity-Based Grid Connection Process For BESS And Large-Scale Consumers

Background:

Germany’s framework for allocating transmission grid connections is undergoing a fundamental shift.

With effect from 1 April 2026, the four German transmission system operators (50Hertz, Amprion, TenneT and TransnetBW) have introduced a new, maturity-based procedure (the Reifegradverfahren) for the allocation of grid connection capacity for large-scale consumers and storage projects, including battery energy storage systems (BESS), data centres and electrolysers.

The reform marks a departure from the previously applied "first come, first served" (Windhundprinzip) approach, under which grid capacity was allocated in chronological order of application.

The change responds to a significant increase in grid connection requests in recent years, particularly from large-scale storage projects, which have far exceeded both available connection capacity and planning assumptions under the German network development plan. At the same time, the existing allocation model has increasingly been criticised for enabling early-stage or speculative projects to secure connection positions without a realistic prospect of implementation.

This shift reflects a broader European trend. Across a number of jurisdictions, increasing connection demand and growing queue backlogs have prompted a move towards a more structured approach to managing grid access. In Ireland, EirGrid operates connection windows with defined application rounds, while in Great Britain the "Gate 1 / Gate 2" framework introduces staged access to grid capacity based on project readiness. Germany’s new approach sits squarely within this wider shift towards prioritising mature and deliverable projects.

Against this background, the new procedure is intended to ensure a more efficient and system-oriented allocation of scarce grid connection capacity.

How the new process works in practice:

The Reifegradverfahren introduces a structured, multi-phase process, replacing continuous case-by-case handling with periodic allocation cycles. The new framework formally entered into operation on 1 April 2026, marking the first application cycle under the revised system.

Each allocation cycle begins with a three-month information and application phase. During this phase, TSOs publish all relevant information on requirements and criteria for grid connection applications and disclose available connection capacities at substations. Developers must submit a complete application by the end of the three‑month phase (for the first application cycle, the official deadline is 30 June 2026 at 24:00). Each application is subject to a non-refundable application fee of EUR 50,000, and applicants may request an optional completeness check within the first six weeks of the phase.

Where applications exceed available capacity, a cluster study phase follows, which is expected to last approximately five months. During this stage, TSOs assess all submitted applications collectively. This includes verifying admissibility, evaluating project maturity, allocating available capacity and conducting the necessary grid studies. The projects are ranked according to a scoring system built around four differently weighted maturity criteria:

• proof of site control and status of the permitting progress (30%); 
• technical maturity and feasibility of the project from an electrical engineering perspective, specifically in relation to the proposed grid connection (30%);
• the financial and organisational capability of the developer (30%); 
• and grid and system benefits through sharing a potential grid connection point (so‑called co‑location applications) (10%).

The scoring is granular and rewards projects that have progressed beyond conceptual stages – for example, through secured land rights, advanced permitting strategies, concluded offtake contracts or financing arrangements.

In the final offer phase, successful applicants receive a binding grid connection offer. Acceptance of that offer by the applicant requires the provision of a realisation security of EUR 1,500 per MW, which must be posted within a short timeframe (one month). This amount is subsequently credited against the construction cost contribution (Baukostenzuschuss).

Projects that are not successful in a given cycle do not receive a right to additional capacity but may, provided they meet the formal requirements, be carried forward into subsequent cycles without incurring an additional application fee.

Scope and legal basis:

The legal framework for grid connection requests is set out in Section 17(1) Sentence 1 of the German Energy Industry Act (EnWG). Under this provision, grid operators are required to grant grid access on technically and economically reasonable, non-discriminatory and transparent terms. At the same time, Section 17 EnWG does not prescribe a specific allocation methodology where no special statutory regime applies, leaving grid operators with a degree of flexibility in structuring the connection process. 

In the area of transmission grid connections, specific procedures exist for certain asset classes. Renewable energy installations and conventional power plants – typically above 100 MW – remain subject to a dedicated connection regime under the Power Plant Grid Connection Ordinance (KraftNAV). By contrast, German law does not provide for a specific connection regime for large-scale consumers – such as data centres and electrolysers – or for large-scale battery storage systems. In particular, an amendment to the KraftNAV, which entered into force on 24 December 2025, clarified that electricity storage facilities do not fall within its scope. As a result, these projects are governed by the general framework of Section 17 EnWG.

Against this background, transmission system operators have introduced the Reifegradverfahren as a structured framework for allocating grid connection capacity to large-scale consumers and BESS. The scope of the procedure may also extend to distribution system operators (DSOs) where projects connected at distribution level require reinforcement or connection at the transmission level.

The Reifegradverfahren must operate within the constraints of Section 17 EnWG. In particular, the application of maturity criteria and scoring methodologies must ensure transparency, objectivity and equal treatment. Any lack of clarity or consistency in their application may expose the procedure to legal challenge.

Treatment of existing applications:

Projects that have already received a binding grid connection commitment or reservation are expected to retain their position and proceed under the previous regime. 

By contrast, applications that have not yet resulted in a binding offer will generally not be processed further under the old "first come, first served" model. Instead, they must be transferred into the new Reifegradverfahren or withdrawn.

Where applications are transferred, previously paid fees are typically credited. Where applications are rejected during the admissibility stage (i.e. due to failure to meet minimum requirements), a partial reimbursement – typically 50% of the application fee – may be granted.

From a practical perspective, the transition may nevertheless create challenges for developers, particularly where projects were already well advanced under the previous system but had not yet secured a formal reservation. In such cases, the shift to a maturity-based allocation model may materially affect project timelines and positioning.

Outlook and implications for project developers:

For project developers, the message is clear: grid access is no longer a race to submit applications as early as possible. Instead, developers must now demonstrate a defined level of project maturity in order to compete for available capacity within a given allocation cycle.

In practice, this requires earlier and more coordinated project preparation. Developers will need to advance key workstreams in parallel, including the securing of land rights, the development of a robust technical concept and tangible progress on permitting and financing. The preparation of comprehensive technical and commercial documentation will become a central element of any grid connection strategy. At the same time, the increased transparency around available grid capacity – published by TSOs as part of the new framework – and structured allocation process offer a more informed basis for strategic site selection and project planning.

The financial dimension of the process should not be underestimated. Participation in each allocation cycle entails a material upfront financial commitment, both at the application stage and upon acceptance of a connection offer. While certain payments may ultimately be credited against later connection costs, they nonetheless require early liquidity planning.

As the first allocation cycles progress, the practical impact of the new regime – both on project development and on the broader structure of the market – is likely to become increasingly apparent.

The content of this article is intended to provide a general guide to the subject matter. Specialist advice should be sought about your specific circumstances.