Uniper gas storage totals 7.2 billion cubic metres (bcm) of working capacity across Germany, Austria, and the United Kingdom — 5.9 bcm in Germany alone, more than any other single operator in the country. Uniper SE reported adjusted EBITDA of €1.097 billion and adjusted net income of €544 million for full year 2025, meeting its financial guidance and proposing the resumption of dividend payments at €0.72 per share for the first time in four years. Uniper’s current structure is the product of one of the largest industrial rescues in European history: a €13.5 billion German state bailout in 2022 that left the federal government holding 99.12% of the company, and a restructuring programme the company is now actively unwinding on the path to reprivatisation by 2028.
How Uniper Became State-Owned: The 2022 Crisis
Before 2022, Uniper was a Düsseldorf-headquartered energy company majority-owned by Finnish utility Fortum, operating across gas storage, power generation, and commodity trading in Europe. When Russia curtailed gas deliveries to Germany following the invasion of Ukraine, Uniper — which had built substantial exposure to Russian pipeline supply — faced losses running into tens of billions of euros as it was forced to replace contracted volumes at spot market prices orders of magnitude above contracted rates.
The German federal government intervened in stages through mid and late 2022, ultimately acquiring a 99.12% stake through capital injections totalling over €29 billion in combined stabilisation measures. It was the second German industrial nationalisation since the post-World War I railways. The European Commission approved the package in December 2022 under state aid rules, imposing a series of conditions: mandatory divestments to be completed by end of 2026, a prohibition on dividend payments, and a requirement to reduce the state’s stake to no more than 25% plus one share by 2028.
By March 2025, Uniper had repaid €2.551 billion to the federal government — fully settling the reimbursement claims from the bailout — and finished 2025 with an economic net cash position of €2.823 billion. The December 2025 amendment to Germany’s Energy Supply Security Act (EnSiG) restored Uniper’s ability to pay dividends, with the €0.72 per share proposal put to shareholders at the Annual General Meeting scheduled for May 20, 2026. For the broader context of what the 2022 crisis revealed about European gas storage vulnerability, see our analysis of underground gas storage as energy security infrastructure.
Uniper Gas Storage: Sites, Types, and Capacity
Uniper Energy Storage GmbH operates the company’s underground storage portfolio through a combination of cavern and porous rock (depleted field) facilities. The cavern sites — located principally at Epe in North Rhine-Westphalia — are salt cavern formations capable of rapid injection and withdrawal cycles, making them suited to intra-day and short-cycle flexibility products. The porous rock sites, concentrated in Bavaria, include Bierwang and Breitbrunn, which have larger working volumes but slower injection and withdrawal rates, better suited to seasonal storage programmes.
The Breitbrunn facility drew regulatory attention in 2025 when Uniper Energy Storage flagged difficulty marketing 6.2 TWh of remaining working gas capacity for the 2025/26 storage year, citing persistently unfavourable summer-winter price spreads. The company offered the unsold capacity to Trading Hub Europe (THE), the German market area manager, under Section 35c(2) of the Energy Industry Act — a statutory mechanism designed to ensure system-critical storage fills regardless of commercial conditions. The episode illustrated the structural tension between commercially-driven storage operators and the system security function those assets perform.
Beyond Germany, Uniper participates in the Etzel Gas Storage joint venture in Lower Saxony — nine former oil caverns converted to gas storage between 1989 and 1993, shared with Equinor Storage Deutschland and Total Etzel Gaslager. The combined portfolio of 7.2 bcm positions Uniper as one of the most significant gas storage operators in Europe, behind only Snam in absolute European capacity terms.
HyStorage: Testing Porous Rock for Hydrogen
Uniper’s hydrogen storage research programme, HyStorage, is running at a designated drilling site within the Bierwang facility in Bavaria — independent of the main commercial gas reservoir. Led by Uniper Energy Storage as consortium operator, with partners including NAFTA, SEFE (Securing Energy for Europe), RAG Austria, and OGE, the project injects natural gas-hydrogen mixtures at progressively increasing hydrogen concentrations: 5%, 10%, and 20% in successive phases, rising to 100% hydrogen in the final test phase.
The scientific objective is to determine how hydrogen behaves in porous rock formations at reservoir conditions — specifically how it interacts with the geochemistry of the subsurface, whether it migrates or degrades, and what the integrity implications are for compressor and surface equipment. The results are intended to inform the broader question of whether Germany’s and Europe’s existing depleted-field storage infrastructure can be converted for hydrogen at scale, and on what timeline. The Bierwang experiment is among the most practically advanced hydrogen underground storage tests running anywhere in Europe, with direct implications for whether the energy transition can reuse existing gas infrastructure rather than requiring entirely new build.
Uniper has committed €5 billion in total investment through 2030, of which over €2.5 billion is earmarked for Germany specifically. The German investment programme focuses on highly efficient and hydrogen-ready gas-fired power plants, with Uniper positioning to bid two projects into Germany’s planned Kraftwerksstrategie capacity auction in 2026 — a mechanism designed to ensure adequate dispatchable capacity remains available as coal exits and intermittent renewables expand. The intersection of uniper gas storage, flexible generation, and hydrogen-ready infrastructure is explored in our overview of EU gas storage conditions and the 2026 refill challenge.
Reprivatisation and the Path to 2028
Under the EU state aid conditions attached to its bailout, Germany must reduce its Uniper stake from 99.12% to no more than 25% plus one share by 2028 — retaining a blocking minority while returning the company to private capital markets. The German government is pursuing options that include a stock market listing of its stake or a negotiated sale, with Reuters reporting in January 2026 that Berlin is actively working on the mechanism for the reduction.
The EU separately accepted that Uniper cannot divest its Russian subsidiary Unipro — a coal and gas power generation business in Russia — because the assets are effectively frozen under the current geopolitical environment. That condition had been a formal requirement of the EU’s state aid approval. Its waiver removes one of the last structural complications from the reprivatisation process, though the Unipro position remains a stranded asset on the balance sheet.
Mandatory divestments required by the EU have otherwise progressed substantially. Completed disposals through 2025 include: the Datteln 4 coal-fired power plant, Uniper Wärme GmbH (district heating), the 18.26% stake in Latvijas Gaze, the Gönyű gas-fired plant in Hungary, and Uniper’s North American electricity portfolio. The helium business — a specialist industrial gas supply operation outside Uniper’s core European energy activities — is in the sale process, with a 15-year supply agreement with QatarEnergy signed in December 2025 providing supply continuity ahead of the transaction. Residual divestments must complete by end of 2026 under EU requirements.
2025 Financial Results and 2026 Outlook
Full year 2025 adjusted EBITDA of €1.097 billion compared to €2.612 billion in 2024 — a decline that Uniper management described as entirely anticipated, reflecting the normalisation of earnings after exceptional crisis-era returns and the impact of a reduced portfolio following EU-mandated disposals. Adjusted net income of €544 million came in at the top of the guided outlook range. Sales revenue for 2025 was €60.955 billion, reflecting Uniper’s large commodity trading and optimisation activities through its Greener Commodities segment.
The Green Generation segment — covering hydro in Germany and Sweden, nuclear in Sweden, and renewables — posted adjusted EBITDA of €626 million, up from €498 million in 2024, partly because a one-off provision for nuclear waste disposal did not recur. The Flexible Generation segment (gas and remaining coal-fired plant) delivered €596 million, down from €998 million as hedging tailwinds from prior years unwound. Uniper’s economic net cash position of €2.823 billion at year-end — maintained after the €2.551 billion government repayment — gives the company material financial flexibility for its investment programme.
For 2026, Uniper guides adjusted EBITDA of €1.0–1.3 billion and adjusted net income of €350–600 million, with Q1 2026 expected to deliver approximately 40% of the full-year EBITDA range. Management confirmed a well-hedged position for 2026 with no direct exposure to the commodity price volatility driven by Middle East geopolitical risk. The €5 billion investment programme through 2030 — weighted towards Germany’s power and hydrogen infrastructure — represents the structural growth layer sitting beneath the stable regulated-like earnings from storage and transmission assets.
Company Snapshot
| Founded | 2016 (spun off from E.ON); operations date to earlier E.ON predecessor assets |
|---|---|
| Headquarters | Düsseldorf, Germany |
| Majority Shareholder | Federal Republic of Germany (99.12% — subject to reduction to 25%+1 share by 2028) |
| Full Year 2025 Adjusted EBITDA | €1.097 billion |
| Full Year 2025 Adjusted Net Income | €544 million |
| Full Year 2025 Sales Revenue | €60.955 billion |
| Economic Net Cash Position (Dec 2025) | €2.823 billion |
| Gas Storage Capacity (Total) | 7.2 bcm (Germany, Austria, UK) |
| Gas Storage Capacity (Germany only) | 5.9 bcm — largest single-country operator in Germany |
| Key Storage Sites | Epe (cavern, NRW) · Bierwang (porous rock, Bavaria) · Breitbrunn (porous rock, Bavaria) · Etzel (JV cavern, Lower Saxony) |
| Hydrogen Storage Research | HyStorage project at Bierwang — porous rock H₂ injection testing, 5–100% H₂ concentration phases |
| 2026 EBITDA Guidance | €1.0–1.3 billion |
| Investment Programme to 2030 | €5 billion total; €2.5 billion in Germany (hydrogen-ready gas plant, renewables) |
| 2025 Dividend Proposed | €0.72 per share — first dividend since nationalisation |
Why was Uniper nationalised by the German government?
Uniper was nationalised in September 2022 after Russia’s curtailment of gas deliveries following the invasion of Ukraine left the company facing catastrophic losses. As a major buyer of Russian pipeline gas under long-term contracts, Uniper was forced to replace undelivered volumes at spot market prices that were multiples of contracted rates, generating losses running into tens of billions of euros. The German government intervened with a stabilisation package eventually totalling over €29 billion in capital injections, acquiring a 99.12% stake to prevent the collapse of a company critical to Germany’s gas supply system. It was Germany’s second industrial nationalisation since the post-World War I period.
How much gas storage capacity does Uniper operate?
Uniper operates 7.2 billion cubic metres (bcm) of underground gas storage capacity across Germany, Austria, and the United Kingdom. Of that total, 5.9 bcm is in Germany — making Uniper the largest single gas storage operator in the country. Key sites include the Epe salt cavern facility in North Rhine-Westphalia, the Bierwang and Breitbrunn porous rock sites in Bavaria, and the Etzel joint venture cavern facility in Lower Saxony, shared with Equinor Storage Deutschland and Total Etzel Gaslager.
What is the HyStorage project at Bierwang?
HyStorage is a research project led by Uniper Energy Storage at a dedicated drilling site within the Bierwang gas storage facility in Bavaria. The project injects natural gas and hydrogen mixtures at progressively increasing hydrogen concentrations — from 5% up to 100% pure hydrogen in the final test phase — to assess how porous rock formations respond to hydrogen storage at reservoir conditions. The results are designed to inform whether Germany’s existing depleted-field gas storage network can be converted for large-scale hydrogen storage, and what engineering requirements that conversion would involve. Partners include NAFTA, SEFE, RAG Austria, and OGE.
When will Germany sell its stake in Uniper?
Under the EU state aid conditions attached to the 2022 bailout, Germany must reduce its 99.12% stake in Uniper to no more than 25% plus one share by 2028. The German government is pursuing options including a stock market listing of its stake or a negotiated sale. The reprivatisation path was materially advanced in December 2025 when Germany amended its Energy Supply Security Act to allow Uniper to resume dividend payments — a key step in restoring the company’s capital market viability. The EU separately accepted in January 2026 that the mandatory divestment of Uniper’s Russian subsidiary Unipro cannot proceed, removing that condition from the outstanding obligations.
What are Uniper’s investment plans for 2026 and beyond?
Uniper plans to invest €5 billion in total through 2030, with over €2.5 billion committed to Germany. The German investment focuses on highly efficient, hydrogen-ready gas-fired power plants designed to provide flexible dispatchable capacity as coal exits the German grid. The company plans to bid two projects into Germany’s Kraftwerksstrategie capacity auction in 2026. Renewables — including solar farms in the UK, Germany, and Hungary — are also in active construction or commissioning phases for 2026. The HyStorage research project at Bierwang is running in parallel to assess the longer-term feasibility of converting existing gas storage sites for hydrogen.