Solid Oxide at Industrial Scale: What Elcogen's elcoStack E3000 G2 Signals for the Baltics
Elcogen's new elcoStack E3000 G2 pairs 75% fuel-cell electrical efficiency with 33 kWh/kg hydrogen production in a single reversible, mass-manufacturable stack — built in Tallinn. We look at the technology, the 360 MW factory behind it, and what this Baltic deeptech milestone offers regional hydrogen and Power-to-X stakeholders.
NEWS
PtXBaltic
8/13/20264 min read
While still challenged by high costs and low availability, green hydrogen is an increasingly viable route to decarbonising heavy industry and distributed power — and one of the clearest signs of that shift is coming from our own region. In May 2026, Estonia's Elcogen launched the elcoStack® E3000 G2, a reversible solid oxide stack designed from the outset for mass manufacturing, and opened its order book for broader rollout. It is a product announcement, yes. But read closely, it is also a progress report on how far Baltic solid oxide technology has come — from laboratory cells to a 360 MW factory in Tallinn — and a preview of what the region can now offer the European hydrogen economy.
One stack, two directions: the reversible core of the G2
The elcoStack E3000 G2 combines more than 100 of Elcogen's solid oxide cells into a single unit that runs in both directions. In fuel cell (SOFC) mode it delivers 3 kW of electrical output at up to 75% electrical efficiency — rising towards 90% total efficiency when waste heat is recovered. In electrolysis (SOEC) mode the same hardware takes in 9 kW and produces around 3 Nm³ of hydrogen per hour at roughly 33 kWh per kilogram — a figure that puts high-temperature electrolysis well ahead of the low-temperature alternatives, which typically need considerably more electricity per kilogram of hydrogen.
The physics behind that number is worth understanding. SOEC splits steam rather than liquid water, at operating temperatures of 650–720 °C. The heat does part of the work that electricity would otherwise have to do, and reaction losses fall as temperature rises. Elcogen states its electrolyser stacks consume about 30% less power than alternative technologies — which translates directly into less renewable generation, less land and less capital per kilogram of green hydrogen. These are the company's own figures, not independently audited, but they are consistent with what high-temperature electrolysis literature has promised for years. The G2's contribution is packaging that promise into a compact, 33 kg, manufacturable unit.
From bespoke projects to repeatable product
The most consequential line in the launch may be the least technical one. Elcogen's CEO Enn Õunpuu framed the G2 as enabling "a transition from bespoke, project-based deployments to repeatable, industrial-scale rollout." That is the exact transition the whole hydrogen sector has been waiting for. Bespoke projects carry bespoke costs; repeatable products ride a learning curve down.
The G2 was engineered for that curve: a simplified, manufacturing-ready design that reduces cost per kW today and establishes a clear pathway to further reductions through volume production. Behind it stands the ELCO I facility in Tallinn — 14,000 m² of production space that lifted Elcogen's capacity from roughly 10 MW to 360 MW a year, with a stated route to multi-gigawatt scale. Elcogen also offers a licensing model under which partners can reach production readiness in about 14 months, meaning the manufacturing recipe itself becomes an export product. For a technology category long criticised as hand-built and expensive, that is a structural change, not an incremental one.
Durability and dynamics: built for real grids, not lab benches
Degradation has historically been solid oxide's weak point — high temperatures age materials. The G2 targets exactly this, with a longer operational lifetime, slower degradation and better wear resistance than its predecessor. Just as important for systems paired with wind and solar, the stack holds efficiency across a wider load range, with strong partial-load stability and stable performance under thermal and load cycling. In a Baltic power system increasingly shaped by variable renewables — and by the price volatility that follows — equipment that tolerates dynamic operation is not a nice-to-have. It is the difference between a technology that works on paper and one that earns money on the market.
Fuel flexibility opens near-term markets
In fuel cell mode the G2 is notably omnivorous: hydrogen, natural gas, LNG, biogas, methanol, ammonia and other hydrocarbon fuels can all feed it, with most hydrocarbons convertible to electricity when paired with a fuel processing system. That matters commercially, because it decouples deployment from hydrogen availability. A combined heat and power system or off-grid genset can run on biogas or natural gas today and shift to hydrogen or e-fuels as supply matures — lowering OPEX now and futureproofing the investment.
The application list Elcogen highlights reads like a map of the coming decade's demand: onsite power for data centres, green steel, ammonia synthesis and hydrogen-intensive chemical processes, residential heat and power, off-grid EV charging. Several of these are live conversations in our region already — from data-centre siting decisions drawn to the Baltics' renewable build-out, to biomethane resources looking for higher-value uses than grid injection.
This is Baltic deeptech, and it is compounding
Step back from the datasheet and the larger story is regional. A company headquartered in Harju county, Estonia, has moved through the full deeptech arc: cell chemistry, stack engineering, a purpose-built factory, and now a second-generation product aimed at global volume markets — collecting recognition from the Global Cleantech 100 and TIME's top greentech rankings along the way, with support from NextGenerationEU and Horizon 2020 programmes. The Baltics are often described as hydrogen's periphery. Elcogen's trajectory argues the opposite: on solid oxide technology specifically, the region is at the frontier.
For the Latvian hydrogen ecosystem, the lesson is less about copying Elcogen and more about connecting to it. Component and materials suppliers, balance-of-plant engineering, system integrators, research groups working on high-temperature materials and heat integration — all of these can plug into a solid oxide value chain that now has a 360 MW anchor two hours up the road. And the SOEC side pairs naturally with Power-to-X: high-temperature electrolysis can absorb waste heat from ammonia synthesis, methanol production and steel making, pushing overall plant efficiency up precisely where Baltic PtX concepts need it.
The stack at a glance
Power: 3,000 W output (SOFC) / 9,000 W input (SOEC)
Hydrogen production: ~3 Nm³ per hour at ~33 kWh/kg (SOEC)
Electrical efficiency: up to 75% (SOFC); ~90% total with heat recovery
Operating temperature: 570–720 °C (SOFC), 650–720 °C (SOEC)
Size and weight: 189.1 × 229.5 × 283 mm, 33 kg
Fuels: hydrogen, natural gas, LNG, biogas, methanol, ammonia, other hydrocarbons
What this signals for Baltic hydrogen ecosystem stakeholders
Three things are worth taking from this launch. First, high-temperature electrolysis has moved from promising to purchasable — the order book is open and deliveries to key partners are underway, so PtX project developers modelling 2027–2030 plants should be pricing SOEC seriously alongside PEM and alkaline. Second, the cost story now runs through manufacturing scale, not laboratory breakthroughs; the winners will be those who design for volume, and the Baltics have a demonstrated playbook for it. Third, and perhaps most useful: the region's credibility in hydrogen no longer rests on ambition documents. It rests on a factory in Tallinn shipping stacks. That is a foundation the whole Baltic hydrogen and Power-to-X ecosystem can build on — and one worth telling openly when we make the case for investment in this region.
Source: elcoStack® — Elcogen