What Blykalla does

Blykalla AB is a Swedish private nuclear technology company founded in 2013 as a spin-off from the Royal Institute of Technology (KTH) in Stockholm, where its founders conducted lead-cooled reactor research beginning in 1996. The company develops the SEALER (Swedish Advanced Lead Reactor), a 55 MWe passively safe small modular reactor (SMR) cooled by liquid lead, featuring a compact 5x5 meter footprint, 25-year fuel residence time, and proprietary aluminum alloyed steels (AFS) that solve the historical corrosion challenge of lead coolant. Its intellectual property extends to uranium nitride fuel manufactured via Spark Plasma Sintering. Blykalla serves hyperscale data center operators, energy-intensive industries, utilities, and — via co-development partners — the maritime and nuclear-powered data center segments.

The company's business model is project-based with multi-year contracts: revenue will derive from SEALER-55 reactor sales, deployment services, and long-term power purchase agreements, supplemented by Swedish government financing support (loans, Contracts for Difference, and risk/profit-sharing mechanisms). Go-to-market combines direct enterprise sales in Sweden/Europe and the United States (New York office opened March 2026), strategic co-development partnerships (notably Oklo for transatlantic deployment, ABB for electrical systems, and ESAB for materials industrialisation), and direct engagement with regulators (Swedish government for Norrsundet, U.S. NRC for pre-application). The company is pre-revenue with serial production targeted for the early 2030s; near-term milestones include the SEALER-E electrical prototype under construction at Oskarshamn, the FJÄLL demonstration reactor planned with Oklo in the U.S., and the first commercial application for the 330 MW Norrsundet reactor park (six SEALER units). As of April 2026, the team exceeds 100 employees and the company has raised approximately $65M+ in equity from strategic investors including Oklo, Norrsken Launcher, Armada Investment, KDDI, and CoreWeave co-founders.

Name

Blykalla

Legal name

Blykalla AB

Website

https://blykalla.com

Company type

Private

Founded year

2013

Operating status

Operating

Headcount range

11–50 employees

Short description

Blykalla is a Swedish nuclear technology company developing the SEALER, a 55 MWe lead-cooled small modular reactor for hyperscale data centers, industrial facilities, and utilities. The company is pre-revenue, with first commercial deployment targeted for the early 2030s.

Ownership category

akta.pro rank

Product category

Small Modular Reactors (SMRs)

SIC

Cogeneration Services & Small Power Producers (4991)

akta.pro primary industry

Small Modular Reactor (SMR) Power Generation (EUACADAF)

akta.pro secondary industries

Small Modular Reactor (SMR) Platforms & Balance-of-Plant Integration (EUAKADAA), Fast Neutron Reactor (SFR/LFR) Power Generation (EUACADAE), Gen IV / Advanced Reactor Systems (SFR, LFR, GFR, MSR, HTGR, Microreactors) (EUAKADAC)

Keywords

• Small modular reactors
• Lead-cooled reactors
• Advanced nuclear energy
• Clean baseload power
• Nuclear reactor technology

Headquarters

HQ city

Stockholm

HQ country

Sweden

HQ region

Europe

Offices3 records

Markets served

GTM type

B2B

Offering type

Hardware or Manufacturing

Cost components

Personnel, Technology or R&D, Operations, Infrastructure, Supply Chain, Marketing or Sales

Revenue model

1. SMR Reactor Sales and Deployment: Sale of SEALER-55 nuclear reactors (55 MWe capacity each) to industrial customers, utilities, and data center operators. Revenue derived from reactor construction, licensing, and deployment services. Expected to begin serial production in early 2030s.
2. Power Purchase Agreements: Long-term contracts for reliable, continuous baseload power delivery to industrial users and data centers. Aligns with energy-intensive customer demand for predictable, carbon-free power supply.
3. Government Financing Support: Support from Swedish government financing model including government loans, Contract for Difference (CfD), and risk/profit sharing mechanism for first-of-a-kind nuclear projects.

Pricing tiers

Go-to-market motion2 records

Distribution channels4 records

Marketing channels7 records

Core offering

Blykalla develops and commercializes lead-cooled small modular reactors (SMRs) under the SEALER (Swedish Advanced Lead Reactor) brand for clean baseload power generation. The flagship commercial unit, SEALER-55, produces 55 MWe per reactor with passive safety systems and a compact 5x5 m footprint designed for off-grid deployment. The product roadmap spans a research prototype (SEALER-E), a demonstration unit (FJÄLL), and the commercial SEALER-55, targeted at utilities, data centers, energy-intensive industry, and maritime customers.

Product overview

Blykalla is developing and commercializing lead-cooled advanced modular reactors (AMRs) under the SEALER brand. The product portfolio includes SEALER-E (electrical prototype testing platform in Oskarshamn), FJÄLL (first nuclear demonstration reactor in the U.S. with partner Oklo), and SEALER-55 (commercial 55MW units for serial production). The core technology combines proprietary alumina forming steels for corrosion resistance in lead coolant with uranium nitride fuel featuring 25-year residence time. All reactors feature passive safety through natural convection cooling and compact 5x5 meter footprints enabling factory production and flexible deployment.

Differentiator

Problem solved

Functional benefit

Brands

• SEALER: Swedish Advanced Lead Reactor - a 55 MWe lead-cooled advanced modular reactor (AMR) designed for commercial power production in a highly compact format. Features passive safety, 25-year fuel residence time, and proprietary aluminum alloyed steel for corrosion resistance.
• SEALER-55
• SEALER-E
• FJÄLL
• ARTS

Products and services

• SEALER (Swedish Advanced Lead Reactor) Lead-cooled small modular reactor product line delivering clean baseload power for utilities, data centers, and energy-intensive industry. Designed for passive safety via natural convection, a 25-year fuel residence, and a compact 5x5 m footprint.
• SEALER-E

Quantifiable outcome

• 330 MW capacity from six SEALER reactors at Norrsundet, producing 2.76 TWh annually (13% of Sweden's 2035 nuclear target)
• +7 more outcomes

Named customers2 records

Segments5 records

Ideal customer profiles4 records

Technology focussed Yes

API detail

Has API

No

API docs

API detail

Core technology

AI maturity

App detail

Feature4 records

Partnerships

14 partnerships are on record, tiered strategic, core and minor.

• Hitachi EnergystrategicTechnology or Integration · 3 July 2026Partnership to develop standardized electrical systems for advanced modular reactors. Focus on creating repeatable frameworks for grid connections, on-site electrical systems, and digital tools to reduce custom engineering at each installation. Targeting data centers and energy-intensive industries.
• ABBcoreTechnology or Integration · 29 April 2026Joint Development Agreement signed April 2026 formalizing partnership from October 2024 MoU. Jointly developing key elements of electrical prototype reactor and establishing framework for demonstration and commercial units. ABB serves as key partner for automation, control systems, and control room equipment. Joint Steering Committee and formalized IP ownership principles established. Also collaborating on maritime sector applications.
• ESABstrategicTechnology or Integration · 5 March 2026Joint Development Agreement signed March 2026 to industrialize Blykalla's proprietary Alumina Forming Steels (AFS). ESAB leads formulation, production, and optimization of alloy-matched filler metals and welding parameters for reactor internals. Combines Blykalla's materials innovation with ESAB's manufacturing capabilities.
• Oklo Inc.coreStrategic or Co-development Partner · 18 December 2025Strategic transatlantic partnership for fast reactor commercialization. Oklo invested $50M co-leading Blykalla's December 2025 funding round. Expanded partnership involves $100-200M investment and 30-40 engineers from Blykalla supporting Oklo's DOE-authorized reactor pilot project, including neutronics and thermohydraulics analyses. Oklo CEO Jacob DeWitte appointed to Blykalla's Board of Directors in April 2026. Joint work on fast-neutron irradiation testing and potential fuel needs.
• evrocstrategicStrategic or Co-development Partner · 6 October 2025MoU signed October 2025 to explore development of Sweden's first nuclear-powered data centers. Evroc building hyperscale cloud/AI infrastructure, combining with Blykalla's SMR technology and Studsvik's licensed nuclear site.
• StudsvikstrategicStrategic or Co-development Partner · 6 October 2025Partnership with Blykalla and evroc to explore nuclear-powered data centers at Studsvik's licensed nuclear site in Nyköping. Studsvik provides site infrastructure and nuclear competence.
• UnipercoreTechnology or IntegrationOne of world's largest power producers (~22.5 GW capacity) partnering on electric research reactor in Oskarshamn. Together with OKG, KTH, and Swedish Energy Agency, constructing electric test reactor with 99 MSEK grant support.
• KSBstrategicTechnology or IntegrationEngineering collaboration on key reactor component (lead pump) for SEALER technology. LOI signed January 2025. KSB brings pump technology expertise for liquid metal coolant systems.
• RISEstrategicStrategic or Co-development PartnerStrategic partnership announced August 2025 to support SMR development in Sweden. RISE (Research Institutes of Sweden) brings research infrastructure and testing capabilities.
• IFEstrategicStrategic or Co-development PartnerPartnership announced April 2025 to advance key primary systems for scalable SMR deployment. IFE (Institute for Energy Technology) brings nuclear research expertise.
• newcleostrategicStrategic or Co-development PartnerPartnership announced February 2025 for R&D collaboration on lead-cooled SMRs. Also considering co-investment in Oklo/newcleo $2B U.S. nuclear fuel fabrication project and procuring fuel services.
• Norsk KjernekraftstrategicStrategic or Co-development PartnerMoU signed February 2025 and joint SMR site project launched June 2025 in Norway. First joint SMR site project for Blykalla outside Sweden.
• Hörby MunicipalityminorStrategic or Co-development PartnerAgreement signed June 2025 for SMR feasibility study in Hörby municipality, southern Sweden.
• Kärnfull NextminorStrategic or Co-development PartnerSMR project developer that submitted Sweden's first SMR application in April. Studsvik acquired Kärnfull Next, with Blykalla also planning SMR park applications - different projects but same ecosystem.

Scale indicators15 records

Recent moves8 records

Expansion highlights8 records

Direct peers

• Oklo: U.S.-based advanced reactor developer building the Aurora liquid-metal-cooled fast reactor. Directly comparable to Blykalla as both pursue compact fast-spectrum SMRs for data center and industrial customers, and the two companies are now active strategic partners with Oklo co-leading Blykalla's December 2025 funding round.
• newcleo: UK/Italian-headquartered developer of lead-cooled fast reactors (LFRs) targeting commercial SMR deployment in Europe. The closest direct competitor to Blykalla's SEALER, with overlapping technology choice (lead coolant), European footprint, and even shared talent lineage (Blykalla's VP Partnerships co-founded newcleo).
• Rolls-Royce SMR: UK-based SMR consortium developing a 470 MWe light-water pressurized water reactor for UK and global deployment. Directly comparable as a European-headquartered SMR targeting utility and industrial customers with serial-manufactured modular units, although at significantly larger output per reactor than SEALER-55.
• Kairos Power: U.S. developer of the KP-FHR fluoride salt-cooled high-temperature reactor with active construction at its Hermes test facility in Oak Ridge and Google as power off-taker. Comparable advanced-reactor developer pursuing non-light-water cooling and industrial/data-center customers, with similar regulatory and supply-chain risk profile.

Broad incumbents

• TerraPower: Bill Gates-backed U.S. advanced reactor developer building the Natrium sodium-cooled fast reactor, with construction underway in Kemmerer, Wyoming. A broader incumbent in advanced nuclear with deeper capital, an operating FOAK project, and Bill Gates' profile, but pursuing a different coolant (sodium) and a larger 345 MWe unit size.
• X-energy: U.S. developer of the Xe-100 high-temperature gas-cooled reactor (HTGR) with Dow as anchor industrial customer and active NRC licensing progress. Comparable as an advanced modular reactor targeting industrial decarbonization and data centers, but uses TRISO fuel and gas coolant rather than liquid metal.
• NuScale Power: U.S.-based SMR developer and the only company with full NRC design certification for its VOYGR light-water SMR. Relevant as the SMR category leader by regulatory milestone, but light-water technology is the conventional incumbent pathway that Blykalla's Gen IV LFR explicitly differentiates against.
• Holtec International: U.S. nuclear equipment manufacturer developing the SMR-160, a 160 MWe pressurized light-water SMR. Comparable as an established nuclear industrial company extending into the SMR category with factory-built units, though based on conventional light-water technology rather than advanced coolants.

Emerging players

• Last Energy: U.S./Polish developer of a 20 MWe microreactor-style SMR targeting European data center and industrial customers with a power-purchase-agreement business model. Comparable as a smaller-output, factory-built SMR pursuing the same data center and industrial baseload thesis, but with light-water rather than lead coolant.
• Moltex Energy: UK/Canada-based developer of the Stable Salt Reactor — a molten salt fast reactor with active engagement in New Brunswick and UK nuclear programs. Comparable as an emerging advanced-reactor player pursuing modular deployment for grid and industrial customers, though using molten salt rather than liquid metal coolant.

Market position

Strengths5 records

Weaknesses5 records

Competitive moat6 records

Key risks6 records

Key highlights7 records

Customer concentration

• YouTubeyoutube.com/@Blykalla
• LinkedInlinkedin.com/company/87388245

Revenue estimate

Valuation estimate

Number of profiles

Profiles10 records

Funding overview

Funding rounds4 records

Investors9 records

Funding detail is available on the Subscription and Enterprise plan.Contact sales →

M&A

Investments

M&A and investment is available on the Subscription and Enterprise plan.Contact sales →

Frequently asked questions about Blykalla