Grid connection for large battery storage, from the request to the offer
For a large battery, the grid connection often decides earlier than the hardware. I sort the preliminary enquiry, the formal request and the connection offer before a reservation or a construction-cost contribution becomes expensive. I do not build the plant and I do not file the request as the network operator.
What should be clear before the first enquiry
Network operators do not ask for a product name. They ask for the site, the voltage level, active and reactive power, whether the battery imports, exports or both, and how it will be operated. Clarifying that after the enquiry produces questions, not a usable answer.
A preliminary enquiry is not a reservation and not a connection offer. It shows whether capacity at that point is even conceivable. Forms and deadlines differ between the transmission grid and the distribution grid, and again from one network area to the next.
From the request to the offer
The usual path runs from the preliminary enquiry through the formal connection request to a reservation and only then to a connection offer. Evidence of project maturity sits in between. Since April 2026, transmission operators, described publicly by TenneT and Amprion among others, use a maturity process for this. Distribution operators have their own conditions.
An offer names capacity, the connection point and usually conditions. It is not a construction contract and not a marketing contract. Whether a construction-cost contribution is then charged, and on what basis, is decided by the responsible operator. There is no national price list on this page.
What the mandate covers
I read the operator’s conditions against your project: site, mode of operation, timetable, and whether the battery stands alone, behind demand or next to generation. The result is a sequence, not a template to file on your own.
Filing with the operator, plant design and construction stay with you and your planners. I advise. I am not a network operator and not an installer.
In the same context
Not legal advice and not an operator’s offer. Conditions, deadlines and costs are those the responsible operator publishes.
Common questions
Is a preliminary enquiry enough?
No. It only tests whether capacity is conceivable. Reservation and the connection offer are separate steps with their own evidence. The responsible operator’s conditions say what is required.
Does the maturity process apply to every battery?
The process transmission operators describe from April 2026 applies to requests on the transmission grid. Distribution grids follow the local operator. Site and capacity decide which one you are in.
Do you file the request?
No. I sort the request and say which documents and which order I see. The connecting party files it, not me as a network operator.
How does AgNeS relate to the connection?
AgNeS (case GBK-25-01-1#3) was still a draft determination on 7 October 2026, not a decision. A connection offer and the draft’s grandfathering rules are two different questions.