TenneT invested €14.8 billion in grid investments in 2025

Group CEO, Manon van Beek, commented: “The investments we made onshore and offshore to future-proof electricity infrastructure in the Netherlands and Germany directly contribute to political and societal ambitions, strengthening Europe’s competitiveness, economy, resilience, and long-term prosperity.”

Despite the growing infeed from renewable energy sources and the additional pressure this places on grid stability, grid performance remained high, with onshore grid availability at 99.99977%.

Financial results update

Underlying revenue in 2025 increased by €671 million to €9101 million (2024: €8430 million). This was due mostly to TenneT Holding's higher investments, resulting in a growing regulatory asset base. In 2025, underlying EBIT increased by €1001 million to €2746 million (2024: €1745 million). This is mainly caused by the increase in revenue, alongside gains from the sale of the activities of NOVEC, partly offset by increased depreciation and amortisation. The EBIT for the Dutch TSO and the German TSO amounted to €992 million (2024: €625 million) and €1588 million (2024: €1087 million) respectively. For non-regulated businesses EBIT amounted to €166 million (2024: €33 million) during 2025.

Dieuwert Inia, Group CFO, commented: “Through investments in our critical high-voltage infrastructure, we are strengthening the energy transition and enhancing economic agility. Failing to invest, or investing too slowly, is not an option if we want to power societal prosperity. At the same time, we remain focused on affordability, through efficient management of our CAPEX and OPEX and by advising the governments on innovative and smart system choices.”

New funding structure safeguards TenneT’s financial position in both countries

TenneT Holding achieved a significant milestone in 2025 that safeguards the group’s financial position by implementing a new funding structure, which resulted in a restructuring of the group senior debt portfolio. TenneT Netherlands and TenneT Germany became two independent TSOs, under the ownership and direction of TenneT Holding. This enables TenneT Netherlands and TenneT Germany to focus on national responsibilities while continuing to collaborate and benefit from group synergies.

Under the new funding structure, TenneT Netherlands received an irrevocable and unconditional guarantee from the Dutch state, supporting investments in the Dutch grid over the next decade. In 2026, TenneT Netherlands expects to raise approximately €6 billion to €8 billion of debt to finance the investments in the Dutch grid. The issue volume may vary depending on market conditions and TenneT Netherlands financing requirements.

Furthermore, in September 2025, TenneT Holding announced a structural financing solution for TenneT Germany, with three institutional investors (NBIM, APG, GIC) committing to invest up to €9.5 billion. This secures the equity required for the expansion of TenneT Germany’s high-voltage grid and positions the company for future growth. In February 2026, this agreement was followed by an agreement with Kreditanstalt für Wiederaufbau (KfW), acting on behalf of the German state, on the sale of a 25.1% stake in TenneT Germany for approx. €3.3 billion. To maintain the 25.1% stake of KfW, primary equity commitments are agreed upon of up to €2.3 billion. Both transactions are pending closing, which is expected by the end of the first half-year of 2026.

The organisational changes also led to changes at executive board level in both countries as well as on Group level. Markus Binder (CFO), Kathrin Günther (CTO), and Ina Kamps (COO) joined TenneT Germany’s Executive Board, chaired by Tim Meyerjürgens (CEO). The TenneT Holding Executive Board includes Manon van Beek (CEO), Dieuwert Inia (CFO), and Maarten Abbenhuis (COO), who also serve on TenneT Netherlands’ board. Dieuwert Inia succeeded Arina Freitag as CFO of TenneT Holding and TenneT Netherlands, effective 1 January 2026.

TenneT Netherlands: achievements and challenges

In the Dutch North Sea, the Hollandse Kust (west Beta) project reached grid readiness, bringing the total number of commissioned 700 MW offshore grid connections to seven. The final connection was completed five months ahead of schedule, on time and on budget.

Onshore, TenneT completed two major grid reinforcements in Zeeland: a 150 kV underground link between Goes and Westdorpe and a 380 kV line from Borssele to Rilland. Work continues on the Southwest East connection in Noord-Brabant, with preparations underway for additional 380 kV projects in Flevoland and between Groningen and Flevopolder.

Despite completing more than 70 Dutch grid projects in the past two years, grid expansion is delayed. Around 60% of the Dutch onshore projects are on average 2.5 years behind schedule, mainly due to lengthy permitting, and complex siting and land acquisition.

Grid expansion will be accelerated by the 2025 Acceleration Package agreed with the Ministry of Climate Policy and Green Growth. The package includes over 30 measures – such as streamlined permitting, early project starts and optimised processes – and could cut project lead times by up to 50%. The TenneT part of this Acceleration Package started immediately in 2025 and will continue to be pursued with urgency and priority in 2026. From 2028 onwards, this Acceleration Package is expected to bear fruit in its entirety.

While grid congestion is certainly not a typically Dutch issue, the company is experiencing the impact of capacity shortages first-hand. Recently, TenneT announced the need for powerful interventions in Flevopolder, Gelderland, and Utrecht to prevent large scale disruptions and power outages in these areas. Working side by side with all stakeholders on solutions for grid congestion, connection queues and constrained transmission capacity, particularly during peak periods, remains a top priority.

In 2025, TenneT Netherlands addressed grid congestion challenges through measures such as Time-Dependent Transmission Rights (TDTR), which shift consumption to off-peak hours. TDTR will unlock up to 9 GW of off-peak capacity and enable flexible grid users to reduce tariffs by up to 65%. In Zeeland, new TDTR agreements unlocked capacity for most queued customers in Zeeuws-Vlaanderen and around 350 MW of additional grid capacity.

Much of the company’s work to unlock additional grid capacity and ensure customers wait less time to be connected to the grid is overseen by a dedicated team in the Netherlands. In 2025, their work successfully realised 53 connections for customers.

In October 2025, TenneT Netherlands published its Onshore and Offshore Grid Investment Plans 2026. The plans show that TenneT Netherlands has more grid expansion projects than ever, with 300 projects added to the Dutch portfolio, bringing the total to around 1000. Between 2025 and 2029, TenneT Netherlands plans to invest €43 billion in the Dutch onshore and offshore grid.

TenneT Germany: achievements and challenges

TenneT Germany completed the offshore converter platforms BorWin Epsilon and DolWin Epsilon for the BorWin5 and DolWin5 grid connection systems, increasing offshore transmission capacity to almost 10 GW. Onshore, Germany’s largest energytransition project, SuedLink, reached a major milestone in October 2025 when final construction approvals were granted in all six federal states, allowing full construction of the 700 km underground DC connection to begin.

While extensive archaeological findings and performance issues with one onshore contractor affected timelines in parts of the DC portfolio, TenneT Germany took clear contractual and steering measures to ensure continued reliable and on-schedule delivery. In 2025, TenneT Germany continued to make significant progress in expanding the onshore AC grid, laying the groundwork for the commissioning of numerous AC projects in 2026. Major milestones include projects such as the Ostbayernring and the Industrieleitung Salzgitter, which will further strengthen grid capacity and support Germany’s energy transition and industrial competitiveness. To maintain this momentum and deliver the infrastructure required for electrification and economic growth, planning, permitting, and land acquisition processes must now be further accelerated and streamlined.

Demand for new grid connections, particularly for battery storage, has risen sharply, often exceeding available grid capacity. While grid expansion and regulatory reforms aim to improve efficiency and flexibility, further decisive action is needed to ensure scarce capacity is used effectively and does not hinder key future technologies. This calls for co-ordinated efforts by policymakers, regulators, and grid operators. At the end of 2025, there were still 391 customer requests for a grid connection pending.

TenneT Germany plans to invest €65 billion in grid infrastructure between 2025 and 2029, to connect offshore wind farms, build large scale DC connections, and expand urgently needed AC lines.

Offshore grid expansion continues despite 2 GW programme contractor change

Fully aligned with the political ambitions of the Netherlands and Germany, TenneT is continuing to expand its offshore portfolio in both countries and plans to more than double its North Sea offshore grid capacity by 2032. Offshore expansion is being advanced together with 10 other North Sea TSOs through the Offshore TSO Collaboration (OTC), which presented the first results of a joint study on an integrated offshore grid in April.

CEO and OTC Chair, Manon van Beek, noted: “Offshore wind and the North Sea as our clean energy powerhouse is not just a climate solution, but a strategic instrument for energy independence and economic competitiveness.”

TenneT Holding also faced setbacks. In June 2023, TenneT signed a framework co-operation agreement with Hitachi Energy and Petrofac for six 2 GW grid connection systems under the 2 GW programme. In October 2025, the company partially terminated the contract related to the Petrofac scope, due to Petrofac not meeting its contractual obligations. Pending completion of a due diligence procedure, Larsen & Toubro will take over Petrofac’s portion of the contract.

Looking ahead

Expanding and modernising the electricity grid is essential to strengthen industrial competitiveness, energy independence and economic resilience in the Netherlands, Germany and across Europe. As electrification – driven by political policy – accelerates, the electricity system must keep pace by integrating renewables, storage, and new industrial demand through large scale infrastructure and smarter use of existing assets.

TenneT Netherlands is assessing which new higher-voltage infrastructure is needed to meet future capacity demands, recognising that the existing 380?kV grid may be nearing its limits. This includes both higher-voltage AC connections and DC solutions, such as inland direct current connections combined with an onshore HVDC hub, alongside flexibility solutions like large scale batteries, and new contracts to better match supply and demand. TenneT Germany has been looking into this for some time and is currently building the first onshore DC connections.

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