AquaVault

Subsurface pumped‑hydro energy storage that creates artificial head with a deep shaft.

The need for offshore energy storage

In 2017, I came across the Ocean Grazer project at the University of Groningen — an academic initiative focused on wave energy, with a little-noticed seabed storage concept that I recognized as the real breakthrough. My prior market research for the EBRD had shown a global blind spot: while offshore wind and solar were scaling rapidly, no one had a solution for grid stability at sea. Experience with Li-ion markets confirmed their strengths for short-cycle storage, but also their fundamental limitations for long-duration applications. This raised a strategic system question: how can we store energy over hours to days, at the scale and speed the transition requires? Traditional pumped hydro was too slow, costly, and geographically constrained — which made Ocean Grazer’s modular pumped hydro solution for offshore, coastal, and flatland settings not only innovative, but urgent.

Modular pumped hydro for scalable energy storage

AquaVault is a modular pumped hydro system that stores surplus energy by pumping water into sealed underground or underwater shafts, and releases it on demand to stabilize the grid. Its design decouples power (MW) and capacity (MWh), allowing flexible scaling from local to utility scale. With fast response times and proven materials, it delivers critical grid services such as curtailment relief and congestion management, while remaining a safe, low-visibility solution suited for offshore, coastal, and flatland markets.

Unlocking pumped hydro where mountains don’t exist

The energy transition faces a structural challenge: balancing offshore renewables and avoiding curtailment requires long-duration storage solutions that go beyond lithium-ion. AquaVault addresses this gap by enabling pumped hydro storage without mountains — a breakthrough for offshore and flatland regions. With its unique technical and ecological profile, Ocean Grazer has emerged as a deeptech innovator, putting offshore balancing firmly on the agenda for industry and policymakers. This urgency has been recognized in national and EU programs such as DOSTA, OESTER, and OASIS, positioning AquaVault as a cornerstone in the search for robust system integration for the North Sea Energy Hub and beyond. ↗

From lab to market: scaling AquaVault as the missing link in energy storage.

I identified the strategic potential of Ocean Grazer’s storage component and led its transformation from academic research into a market-ready company. By reframing the technology as a core product rather than a by-product, I positioned it as the missing link in offshore integration and long-duration storage. Leveraging my international market experience across 49 countries, I built the business case and guided the spin-out into an independent company with its own IP structure, vision, and strategy. Under my leadership, the Ocean Battery scaled into what is now AquaVault — a modular pumped hydro solution suited for offshore, coastal, and flatland applications.

Transfer

Recognition

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