Grid fees for generators from 2029: what Germany's planned feed-in charge costs a solar park and who is grandfathered

Today a solar park pays for its grid connection once: the line to the connection point and the equipment there. Ongoing grid fees are paid only by consumers at the other end. The German grid fee ordinance (Stromnetzentgeltverordnung) puts it in one sentence: no grid fees are payable for feeding in electricity. That rule expires at the end of 2028. In August 2026 the Bundesnetzagentur published a draft that replaces it.

For investors this is not a distant regulatory question. A solar park built or bought today will run well beyond 2029. Whether it pays a feed-in charge, from when and how much therefore belongs in every revenue model. The good news first: the draft protects existing and well-advanced plants generously. The task: that protection depends on dates and evidence you need to know.

Will solar parks have to pay grid fees in future?

Yes, if the draft is adopted as it stands and the park is not grandfathered. Operators of generating plants whose installed gross capacity exceeds 30 kilowatts according to the market master data register must pay (Tenorziffer 9.1). The 30 kilowatts are a threshold, not an allowance: anyone above it pays on the full capacity (Rn. 332). Plug-in solar devices are exempt, as are prosumers at low voltage with consumption below 100,000 kilowatt hours, who pay a surcharge on their standing charge instead.

For a solar park this means: every ground-mounted plant is far above the threshold. Whether it pays depends solely on the transitional rule. The new grid fee system applies from 1 January 2029 (Tenorziffer 1.2); before that, nobody pays a feed-in charge.

Why is the exemption for generators ending?

Because the ordinance that provides it expires at the end of 2028 and the decision now lies with the Bundesnetzagentur. The exemption is in section 15(1) sentence 3 of the Stromnetzentgeltverordnung. That ordinance ends on 31 December 2028, as the legislator decided at the end of 2023 (Art. 15(3) of the Act of 22.12.2023, Federal Law Gazette 2023 I No. 405). The background is a judgment of the Court of Justice of the European Union of 2 September 2021 (C-718/18): Germany had laid down too much of the methodology for grid fees itself in ordinances, although EU law assigns it to the independent regulator.

Since then the Bundesnetzagentur sets the grid fee system itself, based on section 21(3) of the Energy Industry Act (EnWG). The proceeding is called AgNes (Allgemeine Netzentgeltsystematik Strom, the general grid fee system for electricity) and has been running since May 2025. The agency justifies involving generators by arguing that the grid must also be sized for feed-in peaks; if consumers alone bore those costs, the generation side would be artificially subsidised (Rn. 365). Whether one agrees or not: the draft does not extend today's full exemption beyond 2028.

How is the feed-in charge calculated?

As a fixed amount per kilowatt and year, uniform across Germany, billed on the contractually agreed feed-in capacity of the grid connection. What counts is neither the kilowatt hours generated nor the module capacity, but the capacity the connection agreement grants the park (Tenorziffer 9.4). The connecting grid operator collects the money and passes it on to the transmission system operators. There it lowers the nationwide transmission grid fees that all consumers pay.

The four transmission system operators set the rate using a formula in the draft (Tenorziffer 9.3). The numerator has three items: a base component of 0.50 euros per megawatt hour fed in, half of the cost of balancing energy and half of the cost of grid losses in the transmission grid. The denominator is the sum of the agreed feed-in capacities of all plants concerned. The calculation uses actual figures from two years earlier, smoothed over a rolling five-year average. The transmission system operators must publish the rate for the following year by 15 October (Tenorziffer 9.2).

Why exactly 0.50 euros? Because EU law caps transmission charges for generators. Under Annex Part B of Regulation (EU) No 838/2010, the annual average in Germany may range from 0 to 0.5 euros per megawatt hour fed into the transmission grid. Charges for ancillary services and specific grid losses are excluded. The Bundesnetzagentur therefore sets the base component at exactly these 0.50 euros and adds half of balancing and loss costs, which fall under the exclusions (Rn. 375 to 383).

For investors one detail matters more than the formula: the connection agreement becomes a cost item. Agreeing more feed-in capacity than needed costs money every year. Exceeding it risks, according to the agency's considerations, a penalty payment or curtailment without compensation (Rn. 385). And installing more modules than the connection takes costs nothing extra, as long as the agreed capacity is never exceeded (Rn. 386).

How high will the feed-in charge be?

According to the Bundesnetzagentur, probably 4 to 7 euros per kilowatt and year at the start. The range comes from the orientation points of February 2026: 4 euros if only transmission grid costs are included, 7 euros if losses in the distribution grids were added. The August draft only uses transmission costs. Its own model calculation with values from 2020 to 2026 shows how much the annual figure fluctuates and what smoothing does to it:

Two things follow. First, the annual figure fluctuates mainly with the cost of grid losses, which rose with power prices in 2023 and 2024; the five-year average dampens this considerably. Second, the denominator grows with every gigawatt added. If costs do not rise at the same pace, the rate per kilowatt falls. That is no guarantee: the industry had asked for the rate to be fixed for the project lifetime; the agency declined (Rn. 389). For its own revenue forecast it assumes 5 euros per kilowatt (Rn. 369 f.); we use that value as the middle case below.

Which solar parks are spared the feed-in charge?

Solar parks commissioned before the determination is announced, or for which the final investment decision was taken before then, only pay after 20 years from commissioning (Tenorziffer 17.4). The draft sets 1 January 2027 as the day of announcement (Tenorziffer 20). There are two routes to the investment decision:

• With an EEG award: in tenders with a realisation obligation backed by penalties, the bid deadline (Gebotstermin) after which the bid can no longer be withdrawn counts as the date of the investment decision. A longer realisation period provided for in the tender does no harm. A park with an award from a bid deadline up to December 2026 is therefore protected, even if it only connects after August 2029.
• Without a tender, for example a park financed solely through a power purchase agreement: binding orders covering at least half of the investment volume must be in place, from which the operator cannot withdraw without substantial financial loss (Tenorziffer 2 No. 1). In addition, the park must be commissioned by 4 August 2029.

In both cases the operator must prove the investment decision to the grid operator by 31 March 2027. Commissioning means commissioning under the relevant sector law, for a solar park the EEG; a trial run is not enough. Replacing modules or inverters later does not move the date. What counts as commissioning under the EEG and which documents prove it is covered in The commissioning date of a solar park: which date fixes the tariff, the deadlines and the depreciation.

The protection is tied to the plant and its commissioning date, not to the operator. Anyone buying an existing park or a stake in one therefore checks the plant's date, not the date of their purchase agreement. How an existing park and a new build otherwise differ from an investor's perspective is shown in Existing solar park or new build: what changes when the plant is already running?.

One consequence of the rule is easy to miss. For a park with an EEG award, the market premium runs for 20 years from commissioning (section 25(1) EEG); the extension to the end of the calendar year applies only to plants with a statutory value. The grace period for the feed-in charge therefore ends on the same day as the support. From the 21st year of operation, the park loses the market premium and starts paying the charge at the same time. Anyone modelling continued operation, as described in A solar park after 20 years: continued operation, repowering or decommissioning?, has to put both into the same year.

What does the feed-in charge cost a solar park's return?

At 5 euros per kilowatt and full feed-in capacity, around 5,000 euros per megawatt peak and year, just under 10 percent of revenue. That is our own calculation with disclosed assumptions: a park with 1,000 megawatt hours of possible generation per megawatt peak, of which 759 are paid outside negative-price hours; annual revenue is 51,498 euros at an award value of 4.79 cents, calculated with the 2025 generation profile and prices. The revenue side comes from the same calculation as in The direct marketing contract of a solar park: what investors should check before signing.

The biggest lever is the design. Because the charge depends on the agreed feed-in capacity, a park that oversizes its connection with modules pays less per megawatt peak. At a ratio of module to connection capacity of 1.4, it is almost 29 percent less. The price is clipping of the midday peaks. According to our analysis in South, east-west or vertical: which solar park layout pays off for investors, at 1.4 this costs a south-facing plant around 0.8 percent of its yield but at most 0.3 percent of its revenue, because the clipped hours are the cheapest ones.

Over 20 years this adds up. Discounted at 5 percent, 5 euros per kilowatt and year are worth around 62 euros per kilowatt today; at 7 percent, around 53 euros. Across the range of 4 to 7 euros and both discount rates, the charge at full feed-in capacity therefore acts as if the park had cost around 40 to 90 euros more per kilowatt peak. Against construction costs of 600 to 900 euros per kilowatt peak that is noticeable, but no reason to reject an otherwise good park.

It hits the investor harder because the charge is paid before debt service. In our example from Curtailment of a solar park: when the grid operator pays and when it does not, a 5 megawatt park earns 260,000 euros a year. Of this, 156,000 euros go to interest and repayment. That leaves a cash flow to equity of 104,000 euros, before operating costs and taxes. A charge of 5 euros per kilowatt on 5 megawatts of feed-in capacity is 25,000 euros. It reduces this cash flow by 24 percent; at a DC/AC ratio of 1.4 by just over 17 percent, at 7 euros and full capacity by just over a third. For a new park without grandfathering, the charge therefore belongs in the financing model before the bank sizes the loan, not in a footnote afterwards.

Can a solar park pass the feed-in charge on?

Only partly, and only if it is in the price from the start. The Bundesnetzagentur assumes that bidders in EEG tenders will price the charge into higher bids and that unsubsidised plants will include it in the terms of long-term power purchase agreements (Rn. 359 and 360). At the same time it concedes that full pass-through cannot always be expected, because sites differ in cost and competition evens this out (Rn. 362).

For an existing award this route does not exist. The award value is fixed with the award; the determination does not change the market premium. For parks bidding from 2027, bidders can build the charge into their bids; whether it is fully reflected there depends on competition in each round. The draft EEG 2027 does not mention the feed-in charge; what that draft changes about the market premium is set out in EEG 2027: what the refinancing contribution means for a solar park direct investment. With a power purchase agreement, the clause decides: a fixed price without adjustment for new grid fees leaves the charge with the operator. What else matters in such agreements is described in Understanding PPAs: how power purchase agreements make solar park revenues predictable.

What applies to a battery storage system at a solar park?

Under the draft, grid-connected storage pays a capacity charge on its agreed grid connection capacity, at the same level as the feed-in charge (Tenorziffer 10.1). Storage coupled with the solar park pays a single uniform charge together with the plant (Tenorziffer 10.2). Under this rule, storage at the same grid connection does not trigger a second charge; what counts remains the agreed feed-in capacity of the connection (Tenorziffer 9.4). Stand-alone storage has its own transitional rule under section 118(6) EnWG; the details are in Grid fees for battery storage: the exemption until 2029 and the AgNeS reform.

What comes after the fixed feed-in charge?

The draft announces two further building blocks, neither of which has been decided. For generators at grid and transformation levels 1 to 5, dynamic charges that vary by time and region are to follow, not before 1 January 2032 and from 2035 at the latest (Tenorziffer 12.2 and 12.3). A separate determination will set out how they work. A park that feeds in mainly when the grid is congested would then pay more than one that shifts generation; east-west layouts and storage would gain additional value.

The second building block is a construction cost contribution (Baukostenzuschuss) for generators, a one-off payment on connection. The Bundesnetzagentur wants to specify it in a separate process from 2027. According to its orientation points, it would require changes to the EEG, the CHP Act (KWKG) and the power plant grid connection ordinance (KraftNAV). Today the operator bears the cost of its own connection and the grid operator the cost of expanding the grid (sections 16 and 17 EEG). How grid connection and connection costs are handled for a solar park today is covered in Grid connection, easement, building rights: how to tell whether a direct investment has truly secured its site.

What should investors ask about the feed-in charge?

• When was the park commissioned or when is it expected to be commissioned? Which document proves this?
• Does the park have an EEG award? From which bid deadline, and is it before 1 January 2027?
• If there is no award: which orders are binding? Do they cover at least half of the investment volume? Is commissioning by 4 August 2029 realistic?
• Who proves the investment decision to the grid operator by 31 March 2027? Do investors receive a copy of the confirmation?
• Which feed-in capacity is in the grid connection agreement? How does it compare with the module capacity?
• Does the revenue model include a feed-in charge for the period without grandfathering? At what rate?
• Does a power purchase agreement contain a clause passing new grid fees on to the offtaker?
• Is the charge included in the model for operation after 20 years, in the same year the market premium ends?

General checkpoints for any provider are listed in How to tell a trustworthy provider of energy direct investments.

How we check projects for the feed-in charge

For every solar park we present to investors, we record its status regarding the feed-in charge: protected by commissioning, protected by bid deadline, protected by documented orders, or unprotected. For the first three cases we want to see the document the protection rests on. For the third, the proof submitted to the grid operator is part of that. For unprotected parks and for the years after the 20th year of operation, we include the charge at 5 euros per kilowatt of agreed feed-in capacity and additionally show the case at 7 euros. As soon as the Bundesnetzagentur adopts the determination, we will align our assumptions and update this article.

We do not promise returns. We show which figure rests on which assumption. What makes a solar park attractive as a direct investment overall is set out in Investing in solar parks: revenues, costs and tax leverage at a glance. That is exactly what we check with you in a no-obligation initial consultation, gladly using a specific offering document.