The Netherlands Sits on a Hidden Green Energy Goldmine — But the Clock Is Ticking
The Hague, Friday, 12 June 2026.
Deep beneath the Netherlands, salt caverns stretching 1.5 kilometres underground could store enough hydrogen to power Europe’s clean energy future. One cavern alone holds 250,000 MWh — 100 times the capacity of a large surface battery. The window to act is now.
A Salt Core and a Billion-Euro Question
On approximately June 8, 2026, engineers working for chemical company Nobian pulled a salt core — one metre long and 15 centimetres in diameter — from a depth of more than one kilometre beneath the village of Zuidwending, in the northern Dutch province of Groningen [1]. The sample may look unremarkable, but a geologist is currently analysing it to determine whether the resulting salt cavern can be shaped precisely enough to store hydrogen under extreme pressure [1]. It is a small cylinder of rock with an outsized economic and strategic significance: if the geology proves suitable, and if the Dutch government moves quickly enough, this quiet corner of Groningen could become the beating heart of Europe’s hydrogen storage infrastructure [1].
What Nobian and EnergyStock Are Building — and Why It Matters
Nobian, a chemical company based in the Netherlands, is planning to open a new salt extraction site at Zuidwending with a very specific goal in mind: to use the caverns left behind after salt extraction for the storage of green hydrogen [1]. The project is being developed in close collaboration with EnergyStock, a subsidiary of state-owned infrastructure company Gasunie, through its HyStock initiative — described as the first large-scale hydrogen storage project in the Netherlands [1]. Since 2011, the two companies have already been using six salt caverns at Zuidwending for natural gas storage, giving the site a well-established operational track record [1].
The trial drilling currently underway at Zuidwending is expected to last six weeks in total, after which the dismantling of the test site will begin [1]. But the data gathered during this period will be critical. As Louwrens op de Beek, director of energy storage at Nobian, has stated: ‘If we don’t already know now that it will later become hydrogen storage, then we’ll make it a regular cavern — the specific requirements needed for a hydrogen cavern make construction more expensive’ [1]. In other words, the design decisions that determine whether a cavern can safely hold hydrogen must be made before extraction even begins — not after.
The Engineering Challenge: Depth, Pressure, and Scale
Storing hydrogen underground is not simply a matter of digging a larger hole. A hydrogen cavern must reach a depth of up to 1,500 metres — deeper than the standard 1,350 metres used for conventional salt caverns — in order to withstand a maximum internal pressure of 200 bar [1]. According to Op de Beek: ‘That shape and that depth are necessary because hydrogen must be stored under high pressure, a maximum of 200 bar’ [1]. The trial boreholes Nobian is currently drilling at Zuidwending reach depths of more than 700 metres and are designed to assess whether the salt layers can support caverns that, at their base, must be 90 metres wide [1].
The capacity figures involved are striking. A single hydrogen cavern of this type holds one million cubic metres of hydrogen, equivalent to 250,000 MWh of energy [1]. To put that figure in context, that is 100 times the capacity of a large above-ground megabattery, which stores approximately 2,500 MWh [1]. For Thijs de Vries, the Gasunie official responsible for HyStock, the role of storage is more dynamic than the term implies: ‘Unlike what the word might suggest, storage plays a very active role in the hydrogen network. Much of the industry that will switch to hydrogen in the future needs a very stable supply of hydrogen to run their systems safely’ [1].
A National Agenda, a 2027 Investment Decision, and the Risk of Waiting Too Long
The strategic stakes are clearly understood at the national level. In July 2025, the Dutch government published its ‘Nationale Agenda Ondergrondse Waterstofopslag’ (National Agenda for Underground Hydrogen Storage), which set out scenarios requiring between 17 and 40 salt caverns — plus depleted gas fields — for hydrogen storage by 2050 [1]. Currently, just one cavern at Zuidwending is ready for hydrogen storage, with plans to expand to four and eventually, potentially, thirteen caverns [1]. Gasunie has announced it intends to make a final investment decision on the HyStock project by the end of 2027, with the goal of having the first of the four planned caverns operational by 2032 [1].
That timeline, however, leaves very little margin for error. Because the process of leaching out salt caverns takes years, any decision to build storage capacity that could be online sometime after 2030 must be made now [1]. De Vries has flagged a worrying gap in the market: ‘What we see is that the market is giving buying signals too late — in our case, those are the hydrogen producers’ [1]. The construction manager at the Zuidwending site, Erik Jager, offered a pragmatic assessment: ‘The expectation is that in a few years there will be hydrogen storage underground here, and it would be a shame to have to drill so extensively again’ [1].
The Netherlands is not alone in eyeing this opportunity. Suitable salt structures for hydrogen storage are found in the subsurface of the Netherlands, Germany, Denmark, and under the North Sea [1]. Germany, for instance, is already assembling a hydrogen core network of 9,700 kilometres, built from converted natural gas pipelines and newly constructed hydrogen pipelines, with projects such as the Energiepark Bad Lauchstädt set to produce, distribute, and consume 27 million cubic metres of green hydrogen annually [2]. In April 2026, research by EBN and TU Delft found that approximately 150 depleted Dutch gas fields — primarily on the western side of the Netherlands — could also be suitable for hydrogen storage [1], and a pilot project to test hydrogen storage in depleted gas fields is planned to begin in 2030 [1]. EBN and TNO had previously reported in 2022 that offshore storage in salt layers beneath the North Sea is also feasible [1].
For the Netherlands, the salt cavern opportunity carries an added layer of complexity. Nobian’s extraction activities are already the subject of community and environmental scrutiny. Since June 1, 2026, residents of Haaksbergen, Buurse, and Sint Isidorushoeve have been able to apply to an independent Environment Fund seeded by Nobian with a starting contribution of €2.6 million, with the company committing over €24 million in total to the municipality of Haaksbergen over the period 2026 to 2056 [3]. Separately, research programmes including DeepNL and the Dutch Research Council (NWO) began new studies in 2026 into the behaviour of rock salt and the sealing of salt caverns, specifically to model the risks of subsidence and seismic activity [3]. These concerns are not abstract: the Dutch State Supervision of Mines has warned that if companies do not reserve sufficient funds for unexpected events and clean-up costs, risks can arise for the safety of people and the environment [3].
Nonetheless, the geological and economic logic of the Zuidwending project remains compelling. Op de Beek noted that Nobian must expand salt extraction to new locations regardless, in order to keep its salt factory operational [1] — meaning that the caverns will be created whether or not hydrogen storage is the end goal. The question for Dutch policymakers is a simple but urgent one: will those caverns be engineered from the outset to serve Europe’s energy transition, or will the opportunity be shaped by inaction into something far more ordinary?