AgNes: the grid-charge exemption closes on 31 December 2026.

If you operate a commercial or industrial site with on-site generation, a battery, or both, AgNes changes what you pay to be connected to the German grid — not what you pay for power. That distinction is why it has been under-read, and why the deadline attached to it has been missed.

What AgNes is, and who it catches

AgNes is the Bundesnetzagentur's determination proceeding on the design of electricity grid charges. It replaces the StromNEV framework, which expires on 31 December 2028, with a new system effective 1 January 2029.

It is not a solar rule or a battery rule. It is the tariff architecture deciding how the cost of the grid is split, and it reaches consumers, generation plants, storage and electrolysers at once. What is new is that generation and storage start paying a capacity charge at all — historically they have not.

For batteries specifically, the draft has been read by market analysts as close to a best case: the capacity charge is real, but it is roughly a tenth of what household customers pay on the same basis, and the absence of energy-based charges on throughput is the point storage operators had been lobbying hardest for.

The deadline, precisely

Transitional protection does not turn on when your project is finished. It turns on when it is committed.

Protection, once secured, runs for 20 years from commissioning.

What counts as a final investment decision

This is the part that turns a regulatory deadline into a financing one. Under the draft, FID means:

• Binding component orders covering at least half the investment volume — "verbindliche Bestellungen von Komponenten, die mindestens die Hälfte des Investitionsvolumens abdecken".
• Contracts you cannot exit without substantial financial loss. The BNetzA's orientation value is damage exceeding 25% of the investment volume — a cancellation exposure, not a signature.
• Evidence filed with the grid operator by 31 March 2027.

What it costs to miss it

Take a mid-sized C&I site: 260 kW of rooftop PV alongside a 200 kW battery — 460 kW of chargeable capacity.

• At the regulator's worked example of €5.38–5.65/kW/year: roughly €2,475–2,600 a year.
• Over the 20-year protection period that would otherwise apply: approximately €49,500–52,000.
• At the top of the indicated €4–7 band: up to €3,220 a year, or about €64,400 over twenty years.

Fifty thousand euro on a site of that size is not ruinous. It is, however, a cost that appears in no model written before 2026, lands in the years the debt is still outstanding, and is avoidable at zero cost by bringing a decision forward by a few months. That asymmetry is the whole argument.

Scale it and it stops being marginal. The same arithmetic on a 5 MW site is roughly €27,000 a year and over half a million euro across twenty years.

Why we are writing about a tariff rule

Because the question AgNes puts to a C&I operator is one we answer for a living: can this project reach a committed investment decision inside a fixed window, on terms that survive the regime it is being decided under?

• Projects in development have a sequencing problem. Binding orders for half the equipment, with real cancellation exposure, require funding certainty first. Working backwards from 31 December 2026, the financing conversation is not a 2027 problem.
• Existing assets need re-running, not replacing. A site already operating may hold protection. Knowing whether it does, and for how long, changes what the asset is worth and whether refinancing now beats refinancing in 2028.
• Battery storage is not automatically the right answer. The draft is favourable to storage, but a capacity charge is still a charge. Adding a battery to capture the exemption, without a revenue case that stands on its own, is how a good deadline produces a bad asset.
• Lenders are already asking. Banks active in German storage cite regulatory uncertainty around grid fees ahead of merchant revenue risk. A case that addresses AgNes explicitly clears credit committee faster than one that does not mention it.