Consultation on the first draft of the Network Development Plan 2037/2045 (2025) of the transmission system operators. Statement — AquaVentus Förderverein e.V.
14 January 2026. Introduction. The Electricity Network Development Plan (NEP) is a central steering instrument for the long-term planning of energy infrastructure in Germany. The present first draft of the NEP 2037/2045 (2025) addresses numerous challenges of the energy transition — yet one decisive technological development remains unconsidered for the time being: sector coupling by means of electrolysis and the associated cost savings for offshore electricity grid expansion. In view of the projected cost developments in transmission grid expansion, a holistic system development is imperative, one that thinks across sectors and incorporates new technological pathways. A central element is hydrogen production at sea by means of offshore electrolysis, which leads to enormous cost savings. It was expressly named in the coalition agreement and is currently the subject of a comprehensive market consultation by the Federal Ministry for Economic Affairs and Energy (BMWE) on the amendment of the Offshore Wind Energy Act. The AquaVentus Förderverein sees offshore electrolysis as a central option for the efficient sector coupling of offshore wind energy and for securing industry's hydrogen supply. In view of the ambitious targets of the Federal Government and the EU for developing an integrated hydrogen market, it is advisable that this technology be taken into account in the NEP draft — more than that: the NEP must reflect certain degrees of freedom in the planned offshore electricity infrastructure so that the door remains open for technological progress and innovation. The AquaVentus Förderverein advocates a staged, regulatorily accompanied ramp-up of offshore hydrogen production — from the demonstrator through the SEN-1 site to scaled implementation in interplay with the core network (AquaDuctus). This statement names the central points of criticism of the draft and formulates proposals as to how the NEP can be developed further in a cross-sectoral, technology-neutral and forward-looking manner.
Statement on the draft of the transmission system operators. The submitted draft NEP leaves one decisive perspective out of account: the systemic integration of offshore hydrogen production, particularly in Zones 4 and 5 of the Exclusive Economic Zone in the German North Sea (EEZ), by means of combined connection concepts. This gap harbours considerable risks for the economic viability and future viability of offshore wind energy in Germany. It weighs particularly heavily that the coordination sought by the Federal Network Agency (BNetzA) in drawing up the scenarios for further development in the fields of electricity and hydrogen has been taken into account only to a limited extent. For the first time, the electricity scenario framework 2025-2037/2045 and the gas/hydrogen scenario framework 2025-2037/2045 contain joint, overarching assumptions on, for example, the locations of power plants and electrolysers, on the basis of which network development planning for the transmission grid on the one hand and for the gas/hydrogen network on the other can be carried out consistently with one another. This required interlocking of the underlying scenario frameworks is reflected in the submitted NEP draft of the transmission system operators only in part and without any spatial localisation of the electrolysers (sections 2.4.6 "Hydrogen and electrolysers" and 3.3.6 "Hydrogen and electrolysers"). Furthermore, findings from current studies regarding offshore electrolysis and the associated efficiency gains for the energy system are not considered either. In the offshore sector in particular, electricity and hydrogen infrastructure must in future be thought of more strongly together and in an integrated way, both for reasons of cost and because of competition for space — whether via combined connection concepts, offshore energy hubs or integrated expansion pathways. This applies all the more in view of the AquaDuctus infrastructure project, which is of European significance and is listed both as an IPCEI project (Important Project of Common European Interest) and as a PCI (Project of Common Interest). AquaDuctus is intended to play a load-bearing role in the future hydrogen core network and connects offshore hydrogen generation in the North Sea with the mainland. Its absence from the NEP draft contradicts not only integrated network planning but also the European objectives on security of supply and resilience. Chapter 5 of the NEP (5.2.1 "Offshore optimisation measures") relies exclusively on overplanting to reduce energy infrastructure costs. Wind farms are to be deliberately oversized in order to increase infrastructure utilisation. However, the market value of the transported energy, and thus the socio-economic viability calculation (electricity price at the time of generation), is ignored entirely. Furthermore, this concept transfers the full risk of revenue losses to the operators of offshore wind farms, who must be compensated in other ways, such as through a higher electricity price for customers, subsidies or contracts for difference. In addition, this approach jeopardises the profitability of the associated offshore power lines.
The danger of "stranded assets" — offshore power lines without a corresponding wind farm operator on the respective sites — thus rises considerably. Voluntary overplanting of offshore wind farms by 5-10 % has already become common practice in order to increase the quantity of energy provided and the hours of feed-in into the transmission grid at full capacity, with the aim of minimising the levelised cost of electricity (LCOE). In this way, well over 1,000 hours per year at full feed-in capacity can be achieved. An obligation to overplant across the board misses this business optimum for offshore wind farm operators, so that the levelised cost of electricity rises and, in return, wind farm capacity must be curtailed for more than 1,000 hours a year. Cross-sectoral coupling — for instance through the simultaneous build-up of hydrogen infrastructure at sea — offers considerable advantages in terms of grid stability, flexibility and economic scaling. Both the Frontier Economics study "Efficient integration of offshore wind energy through offshore hydrogen production" (Nov 2025) and the E-Bridge study "Assessment of connection concepts for distant offshore wind areas in the German North Sea for an efficient energy transition" (Sep 2024) show that an integrated view of electricity and hydrogen infrastructure leads to significant system cost savings of EUR 1.7 billion per year and to increased security of supply, and can thus make an essential contribution to efficient energy system development. Particularly critical is the statement on page 244 of Chapter 10, according to which the NEP assumes "lower domestic and therefore electricity- and cost-intensive generation of hydrogen". This assumption is not only unsubstantiated but contradicts fundamental strategic objectives of the Federal Government to promote domestic hydrogen production, both onshore and offshore. It negates market integration through the merit order prevailing in the electricity market, technological innovation dynamics and the associated cost degression, as well as the envisaged developments around the SEN-1 area and the AquaDuctus hydrogen pipeline. Not least, the methodology for calculating offshore route lengths is problematic and naive: for grid connection systems beyond Zone 3 — that is, particularly in the distant Zones 4 and 5 of the EEZ — a detour factor of only 1.1 is assumed. It is precisely here that route lengths cause enormous costs. This blanket assumption deliberately underestimates the real challenges and spatial conflicts in the German territorial sea and thereby obscures the actual costs of this line infrastructure.
Demands of AquaVentus: requirements for a technology-neutral Network Development Plan and room for technological development. 1. Integration of sector coupling and cross-sectoral storage into network planning, thereby enabling the system integration of electricity and hydrogen. 2. Consideration of offshore hydrogen generation as a systemic component of the Network Development Plan — building on combined connection concepts and in the spirit of coordinated network planning between electricity and hydrogen infrastructure. 3. Review of spatial and route planning for offshore lines, particularly with regard to realistic cost assumptions. 4. Correction of the hydrogen forecast in order to reflect domestic generation prospects realistically — onshore as well as offshore.
Offshore hydrogen production can contribute decisively to the efficiency and resilience of the future energy system — it must no longer be left out of the Network Development Plan.