Nautilus Data Technologies

Status: Alive — but pivoted. The floating-datacenter thesis is dead; the company now sells liquid-cooling hardware. The most instructive commercial data point in the segment: they actually built a barge, actually leased it to real customers, and still exited the business.

What they built

Founded ~2015 (Pleasanton, CA; founder Arnold Magcale, US Navy vet). Colocation datacenter on a moored barge, cooled by drawing water from the adjacent water body through heat exchangers and returning it ~4°F warmer — no cooling towers, no water consumption. The patented cooling system (TRUE, later productized as "EcoCore") was the core IP; the barge was the demonstration vehicle.

Stockton 1 (the only one ever built): converted 235-ft barge permanently moored at Port of Stockton, CA. Commissioned 2021. ~7 MW critical IT load, ~20,000 sq ft, four data halls, Tier III-level, claimed PUE 1.15.

Funding

Roughly 300Mtotal(equity+debt,trackerfiguresapproximate): 35M equity through 2019 (Keppel, Emerson Collective, Ireland Strategic Investment Fund), $100M debt facility from Orion Energy Partners (2020), $50M convertible round led by UIL (2021), and a Jan 2026 "strategic Series B" led by Pangaea Ventures — for the cooling-product business, not barges.

Customers — real, but modest

This is the segment's only confirmed Western paying-customer evidence, and note what it is: City of Stockton and San Joaquin County (backup/disaster recovery), Backblaze (storage, 2022), Cerebras (AI hardware deployment, 2024), plus a 2.5 MW AI-company contract (Dec 2023). At sale listing: 86% occupancy, 5.58 MW leased. Government DR and cold storage — not hyperscale, not premium workloads.

How the barge business died

• Stockton 1 put up for sale at $45M (~Nov 2024), still on the market. Remaining pipeline described by trade press as "conceptual" and partner-dependent.
• Maine (Millinocket, 60 MW, ~$300M) cancelled April 2025 — reported reason: couldn't land an AI anchor customer because the site couldn't deliver enough power. Site owner called it "dead."
• Los Angeles (AltaSea/Port of LA) and Marseille barges (announced 2022, 7.5 MW each): never built. No formal cancellation — quietly stalled.
• No bankruptcy, no layoffs reported, no acquisition. The company recapitalized around the pivot: EcoCore CDUs (direct-to-chip/immersion cooling for AI datacenters), marquee product customer Start Campus (Sines, Portugal), active hiring through Jul 2026.

Lesson for the segment

Nautilus is the strongest evidence that the water-cooling technology has value but the floating-venue wrapper doesn't: the same company, same IP, found more demand selling cooling into land-based AI datacenters than operating the barge that proved it. Also note the Maine failure mode — power delivery, not cooling — which is the binding constraint in the AI era.

Sources

DCD: barge for sale at $45M · DCD: Maine cancelled · WABI: Millinocket cancellation · Backblaze deployment · Gov Tech: Stockton tenancy · DCF: LA + Marseille announcement · Series B (Pangaea, Jan 2026) · Baxtel facility profile