Transmission system operators 2027 to 2031: six deadlines from the system stability report to the plan-value model

Six deadlines from 2027 to 2031

Five of the six dates fall in 2027 and come round again afterwards: the system stability report every two years, the network development plans in every odd year, and the redispatch forecast, EEG outlook and surcharge every year. Only the sixth is a one-off, aimed at distribution system operators, who are to move plants into the plan-value model of Redispatch 2.0 by 2031. All six rest on law in force or on adopted rulings; none comes from a draft.

These reports build on each other: the redispatch forecast takes onshore wind and solar expansion from the previous year's EEG outlook, and the 2025 system stability report drew on the scenario framework that also underlies the network development plan. A DSO that sends data to its TSO is therefore rarely sending it for one report only.

System stability report on 1 January 2027

By Friday, 1 January 2027, the four TSOs with control area responsibility report to the Bundesnetzagentur on the security, reliability, stability and performance of their network and of the electricity supply system. It is the second report under Section 12i EnWG; the first was due on 1 January 2025, and a two-year cycle applies from then on. System stability here is meant technically: whether frequency and voltage stay within limits after a short circuit or the loss of a power plant.

Subsection 2 is unusually precise about the content. It requires the report to set out the status of every area of system stability, identify the need for action even with electricity generated entirely from renewables, and quantify needs for the next ten years. From that, the TSOs derive options, rate them by effect, implementation time, cost and suitability, and present at least one transformation path with concrete measures. They also have to account for progress: the report must state how far the options named in the previous report have been implemented and explain any delays.

According to the Bundesnetzagentur, the 2025 report covered the years 2027 to 2037. As summarised by the trade paper ZfK on 1 August 2025, it dealt with the loss of inertia and reactive power as conventional plants close, grid-forming support from battery storage, rotating synchronous condensers and STATCOMs (static reactive power compensators), and grid restoration without classic black-start plants. In July 2025 the Bundesnetzagentur published its assessment and added regulatory points, such as targeted procurement of system services. For the 2027 report it has six months from receipt; it then submits its assessment and monitoring report to the Federal Ministry for Economic Affairs and publishes both together with the report (Section 12i(5) and (7)).

Two subsections matter for DSOs. Under subsection 4 they must help prepare the report when a TSO asks, and under subsection 6 they provide the regulator with information for its ongoing monitoring of system stability. We expect these requests to get more specific with each report, because reactive power and inertia are increasingly meant to come from plants connected to distribution grids.

Network development plans: drafts by 31 May 2027

By the end of Monday, 31 May 2027, the TSOs are to publish the draft of the next electricity network development plan, and the coordination office of the gas TSOs must publish the draft gas and hydrogen plan on the same day. Only the wording differs: Section 12b(3) sentence 3 EnWG says "should" for electricity, Section 15c(4) sentence 4 says the gas and hydrogen draft "is to be published". Both drafts go out for consultation; for electricity that means the public, grid users, downstream network operators, public bodies and the state energy authorities.

How much a "should" date can bear is visible in the current cycle. On 30 April 2025 the Bundesnetzagentur approved the scenario framework for the 2037/2045 (2025) plan; the TSOs published the first draft on 10 December 2025 and the second on 16 March 2026. Its consultation on the second draft ran until 24 August 2026, and we had found no confirmation by 27 October 2026, although Section 12c(4) EnWG provides for confirmation by 30 June of even years. For the 2027 cycle, the draft scenario framework has been with the Bundesnetzagentur since 30 June 2026 and its consultation closed on 28 September 2026; no approval had been published by 27 October 2026. Whether the electricity draft appears on 31 May 2027 depends on how early that approval comes, given that a little over seven months passed between approval and first draft in 2025. What the 2027 scenario framework contains is covered in our article on the 2027 scenario framework after the consultation.

DSOs feel the plan in two ways. They must give the TSOs the information needed for the plan without delay when asked (Section 12b(3) sentence 4), and as downstream operators they can comment on the draft. For the gas and hydrogen plan, Section 15c(4) expressly lists gas distribution system operators as affected operators, as well as operators of hydrogen networks that are not transport networks. What the 2025 gas plan contains is covered in the article on the integrated gas and hydrogen network development plan.

Redispatch forecast by 1 July

By Thursday, 1 July 2027, the TSOs jointly send the Bundesnetzagentur their forecast of how many congestion measures under Section 13(1) and (2) EnWG will be needed over the next five years and what they will cost. Its assumptions come from that year's system analysis and the supplementary analyses under Section 3(2) of the Grid Reserve Ordinance; the Bundesnetzagentur publishes the result (Section 13(10) sentences 1 to 4).

In the version of 30 June 2026, total costs for 2027 come to EUR 4,580 million, including EUR 1,098 million in grid reserve standby costs, with 21.95 TWh of redispatch in each direction. By 2029 the figures rise to EUR 4,866 million and 25.13 TWh and then stay flat to 2031. Behind them is a system analysis that covers only two periods: April 2026 to March 2027 and April 2028 to March 2029. For comparison, congestion management cost about EUR 3,071 million in 2025 for a volume of 30,319 GWh, according to provisional Bundesnetzagentur figures on SMARD.

The forecast explains the gap itself: its system analyses are meant to establish the capacity needed for secure operation in a worst-case view, and the volumes and costs derived from them should be "assessed accordingly". It is not much use as a budget figure. It's still worth reading, because it shows what the TSOs assume about grid expansion, the coal phase-out and market coupling, and because congestion costs end up with every grid user through network charges. How DSOs are to be compensated for redispatch in future is covered in the article on redispatch without balancing.

Outlook on renewables and EEG payments by 25 October

By Monday, 25 October 2027, the TSOs prepare and publish two outlooks for 2028 to 2032: on the expansion of renewables under Section 74 EEG and on the payments due for it under Section 60 EnFG. The first contains at least installed capacity, full-load hours and annual generation, with capacity broken down into nine energy sources from hydropower to mine gas and solar additionally split into first and second segment. A second one forecasts payments to plant operators and avoided network charges under Section 18 StromNEV. Both must reflect the state of the art and disclose their data and assumptions.

For 2026, the outlook was prepared by the Forschungsstelle für Energiewirtschaft (FfE) on behalf of TenneT and is dated 26 October 2026, as 25 October 2026 was a Sunday. In the trend scenario, installed EEG capacity grows from 231.1 GW at the end of 2026 to 364.6 GW at the end of 2031, driven by roughly 41 GW more solar each on open land and on other sites, mostly rooftops, and about 37 GW more onshore wind. Payments rise from about EUR 18.3 billion in 2027 to about EUR 22.3 billion in 2029 and fall to about EUR 20.6 billion by 2031. According to the report, the drop in 2031 comes from solar plants built around 2010 leaving the 20-year support period. What drives the increase is the exchange price, which the report sees falling from around EUR 106 per MWh in 2026 to about EUR 70 per MWh in 2030: the lower the market value, the higher the market premium. Changes from the EEG 2027 could not yet be taken into account.

Its main use is as the basis for calculating next year's EEG financing requirement, which the TSOs have put at EUR 17.524 billion for 2027. For DSOs the second part is more relevant than the first, because it also forecasts avoided network charges under Section 18 StromNEV.

Surcharge for special grid use: two components shown separately

Every year by 25 October, the TSOs show separately on netztransparenz.de what two levy mechanisms contribute to the next year's surcharge for special grid use: the surcharge for special feed-in-related grid use from renewables grid cost pass-through, and the mechanism under Section 19(2) sentence 15 StromNEV (BK8-24-001-A of 28 August 2024, operative point 7 sentence 2). They may bill both to grid users as a single item (sentence 1). According to the reasoning, the out-of-period expenses of each mechanism are to be shown separately as well (para. 130).

The calculation of the 2027 surcharge on netztransparenz.de is dated 26 October 2026. Of EUR 5.063 billion in costs to be passed through, EUR 3.454 billion comes from renewables grid cost pass-through, just over two thirds, and EUR 1.609 billion from the items under Section 19(2) StromNEV and the network charge exemption for electrolysers under Section 118(6) EnWG. At 2.027 cents per kWh, the surcharge applies to final consumers up to 1 GWh per offtake point (group A'), after 1.559 cents in 2026; it stays at 0.050 and 0.025 cents in groups B' (above 1 GWh) and C' (above 1 GWh, electricity-intensive companies). All figures are subject to a federal subsidy of EUR 5.525 billion towards transmission costs: if there is no legal certainty by 7 December 2026, the TSOs expect a higher final surcharge. Other levies published for 2027 are covered in the article on levies 2027.

25 October is the end of a chain that starts with the DSOs. A DSO that wants the compensation notifies its regulator of the calculated amount by 1 October and reports it to the TSO by the last working day before 15 October (operative point 5). A late report forfeits the reimbursement for that year. Our article on the 2026 reporting round covers renewables grid cost pass-through in detail.

Plan-value model: transfer by 1 January 2031

By Wednesday, 1 January 2031, DSOs, in coordination with the TSOs, are to move at least all controllable resources that can improve the efficiency of congestion management in the transmission grid into the plan-value model. That is section 2.3.1 of the BilAReM annex to ruling BK6-23-241 of 7 May 2026, with which the Bundesnetzagentur reorganised balancing in Redispatch 2.0. It is the only one of the six deadlines where the DSOs themselves are the obligated party.

Plants a DSO has not transferred stay in the forecast model, where the grid operator does not balance redispatch measures at all until 31 December 2031 (section 2.2); the supplier's balancing group absorbs the effect untargeted. Per grid connection point, the TSOs specify how much installed capacity of which plant type is to be transferred. DSOs then form clusters whose plants switch to the plan-value model in full, and a cluster may not mix the two models. Where plants sit in downstream grids, the upstream and downstream DSOs coordinate, and plant operators' wishes are to be considered as long as they do not get in the way of the transfer.

What makes it tight is the calendar of the assignment procedure (section 2.3.2). A transfer only takes effect on 1 January, 1 April, 1 July or 1 October, and not before the nationwide data formats apply; the instructing grid operator must notify the supplier, the scheduling party and the operator of the technical resource electronically at least six months in advance. A DSO that wants a transfer effective 1 January 2031 therefore has to send the notice by 1 July 2030, having tested communication with every affected market role beforehand. A plant cannot go back to the forecast model. That is why we think the deadline is tighter than the year 2031 suggests: for DSOs with many plants behind grid connection points to the transmission grid, the work starts with agreeing the clusters, long before the first notice goes out.

Where DSOs have to contribute

For five of the deadlines the TSOs are the obligated party, but the data often sits in the distribution grid. Three provisions expressly require DSOs to contribute, each for a different reason.

What applies if a deadline is missed

None of the six deadlines carries its own administrative fine. For the duties under Sections 12b, 12i, 13(10) and 15c EnWG, the regulator can enforce compliance under Section 65(2) EnWG with coercive fines under Section 94 EnWG; failing to comply with an enforceable order is an administrative offence under Section 95(1) no. 3(a) EnWG. For the EEG outlook the law sets no specific sanction, and the Bundesnetzagentur can order a remedy under Section 85(3) EEG with Section 65 EnWG. Rulings BK8-24-001-A and BK6-23-241 set no specific consequence either; the Bundesnetzagentur can order their implementation under Section 65 EnWG.

For the draft electricity network development plan and for the transfer into the plan-value model the date is worded as "should"; the 2025 network development cycle shows how far such a date stretches. Consequences built into the rules themselves bite sooner than supervision, such as the lost reimbursement after a late renewables pass-through report and the impossibility of returning to the forecast model. This is a general assessment for roles, not a review of your individual case.

Criticism and open points

Of the six, the surcharge drew the sharpest dispute. In the consultation on BK8-24-001-A, some respondents asked for a separate levy for the renewables costs, arguing that passing them through the existing Section 19 StromNEV mechanism would reduce transparency for consumers. The ruling chamber rejected this:

Yet the overview page on netztransparenz.de shows only the total surcharge per group for 2027; the split in euros is in the linked calculation PDF, and there is no split in cents per kWh by mechanism. Anyone who wants to explain to customers why the group A' surcharge is rising by just under half a cent has to do the maths themselves.

On the EEG outlook, the German Renewable Energy Federation (BEE) objected, according to pv magazine on 26 October 2026, that it was unclear what battery storage build-out had been assumed; more storage could stabilise market values and lower EEG costs. On the network development plan, the TSOs and the Bundesnetzagentur are apart: of 159 proposed measures, the agency considers 118 confirmable and so far sees no sufficient contribution from the rest to the grid reinforcement needed (press release of 12 June 2026). As of 27 October 2026 it is open when the 2027 scenario framework will be approved and whether the federal subsidy towards transmission costs will arrive in time.

What to do before autumn 2027

Most of the work lies with the TSOs; DSOs and suppliers share the consequences. All dates with roles and systems are also in the energy transition deadline calendar.

Next steps by role

1. Name a contact

   DSOs: set up one point that takes requests on the system stability report and the network development plan and pulls the answer together from grid planning, grid operation and plant master data.

2. Plan for 25 October

   DSOs and suppliers: time the price-sheet and tariff calendar so that the 2028 surcharge can be taken over on Monday, 25 October 2027, with slack for a proviso like the one in 2026.

3. Agree plan-value clusters

   DSOs with plants at grid connection points to the transmission grid: obtain the TSO's specification, form clusters, test market communication with every affected market role, and send the last notice for 1 January 2031 by 1 July 2030 at the latest. Transferring earlier spreads the load over several quarterly dates.

4. Ask for data early

   TSOs: send requests to DSOs for the 2027 report and the network development plan early enough that "without delay" stays achievable for grid operators with small teams.

Further reading

Frequently asked questions