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Greenergy Data Centers
ET Eesti keeles

About

Built where the digital state was born. Expanding for the AI era.

Greenergy Data Centers was established in Estonia in 2020 to give the region's most digital society the physical infrastructure it had been missing. Six years on it runs 2 MW of colocation and a 22 MW built-to-suit hall, and is expanding towards 200 MW.

The Greenergy Data Centers campus in Hüüru, seen from above.

Why we exist

99% of government services online, and nowhere purpose-built to run them.

“Everything that is on the internet has to physically be somewhere.”

Üllar Jaaksoo, founder of Greenergy Data CentersÜllar Jaaksoo, founder of Greenergy Data Centers

By 2020 Estonia had built an efficient, secure and transparent digital ecosystem in which almost every public service is delivered online, and had grown more technology unicorns per capita than any other country. What it lacked was a data center designed and certified for the systems that ecosystem depends on. Across Central and Eastern Europe, sustainable and reliable data centers were in short supply.

With the support of the Three Seas Initiative Investment Fund, Greenergy acquired MCF Group Estonia, which had run into the same gap and was already building a world-class data center outside Tallinn. Joining forces combined the best technical knowledge, management and skilled people to raise the largest and most power-efficient data center in the Baltic region, on a site next to Elering's Harku 330 kV substation. It opened in 2022 and has run at Level 3 availability since.

In July 2026 Tensor Estate, a developer of AI factories, became a shareholder and fit-out of a 22 MW built-to-suit hall for the latest NVIDIA generation began inside the existing building, alongside the colocation halls. The long-term objective is broader still: a network of sustainable data centers across Central and Eastern Europe.

Guiding principles

Four commitments from day one.

Reliable

Multi-layered security on the grounds and inside the building: round-the-clock armed surveillance, several hundred cameras and graded security zones. Every visitor is identified and moves only in the rooms designated for them. Redundant power and cooling systems are maintained and tested on a schedule, and the NOC serves customers 24/7.

Efficient

A full-load PUE below 1.2: for every kilowatt-hour that reaches your equipment, less than 20% is added for cooling, connectivity, security and reliability. The global average in 2025 was almost 60%.

Sustainable

Your equipment runs only on electricity from renewable sources, cooled on a closed loop that consumes no water, and the cooling plant is optimised continuously by Siemens AI.

Customer-focused

A solid foundation for your IT infrastructure and a working relationship built around business continuity: no wondering whether power, cooling or security will hold, or whether there is room to grow. Experienced specialists design custom solutions for large projects, with the interests of other customers in mind.

Ownership

Our shareholders.

3SIIFTensor Estate

The Three Seas Initiative Investment Fund (3SIIF), advised by Amber Infrastructure, invests in critical infrastructure across Central and Eastern Europe and sits on the joint Supervisory Board with Tensor Estate.

Tensor Estate develops AI factories across Europe and brings international AI cloud and hyperscale customers to its sites. It became a shareholder in MCF Group Estonia in July 2026 and sits on the joint Supervisory Board with 3SIIF.

MCF Group Estonia builds and runs the facility. Day-to-day operations remain with the team that built it, led by CEO Kert Evert.

amberinfrastructure.com tensor.estate

Who is involved

Timeline

From a gap in the map to a 200 MW campus.

  1. 2020

    Founded in Estonia

    Estonia had built a digital ecosystem in which 99% of government services are online, yet the region lacked a purpose-built, high-security data center. Greenergy was established to close that gap.

  2. Dec 2020

    MCF Group Estonia acquired

    The Three Seas Initiative Investment Fund took a controlling interest in Greenergy, which in turn became the full owner of MCF Group Estonia and its data center project outside Tallinn.

  3. 2022

    Campus opens in Hüüru

    The 14,500 m² facility goes live next to Elering's Harku 330 kV substation, built for expansion from day one. EN 50600 certified; level 3 availability from commissioning.

  4. Jul 2026

    Tensor Estate joins; expansion starts

    Tensor Estate becomes a shareholder alongside 3SIIF. MCF Group starts building the 22 MW built-to-suit hall with Caverion as main contractor, on a campus with a 200 MW grid connection.

  5. Aug 2026

    22 MW built-to-suit hall announced

    An AI cloud customer, Nebius, takes the 22 MW built-to-suit hall for an NVIDIA GB300 cluster: the region's first AI factory. Together with 2 MW of colocation, the current campus is almost fully leased.

  6. Late 2026

    The 22 MW hall goes live

    The built-to-suit hall enters production, direct liquid cooled on a closed loop, alongside the colocation halls.

  7. Early 2028

    Next capacity

    A further built-to-suit phase opens beyond the 22 MW hall, designed for NVIDIA Vera Rubin. Reservations are open now.

How we operate

Five commitments to all customers.

The Greenergy operations control center, staffed around the clock.
Security
Multi-level access control with anti-passback, palm biometrics, AI-driven security systems and CCTV with analytics, operated on a zero-trust philosophy. ISO 27001 and PCI DSS AOC certified.
Connectivity
Cloud- and carrier-neutral, with eight fibre backbones entering from four directions, logically and physically redundant networks and optical connectivity from anywhere to anywhere inside the building.
Reliability
Redundant power, cooling and connectivity throughout; Level 3 availability since commissioning in 2022. EN 50600 and ISO/IEC 22237 Availability Class 3 certified by TÜV NORD CERT (certificates 661370.26 and 661469.26), ISO 27001 and ISO 9001; Drees & Sommer operational maturity 83%.
Scalability
A modular structure that grows, with headroom built into power distribution, backup and cooling, so capacity can be added without disturbing what is already running: from 24 MW today towards a 200 MW campus.
Sustainability
PUE below 1.2, certified renewable energy and closed-loop cooling that uses no water.

Fibre-optic cable routes

The fibre-optic cable routes of MCF Group Estonia OÜ (operating as Greenergy Data Centers) are managed and maintained by Lansec Tele OÜ under a cooperation agreement. Lansec coordinates projects in the protection zone of the routes, issues technical conditions and work permits, and repairs faults.

Questions, applications and requests about the routes: mcf@lansec.ee, +372 503 8713

Careers

Greenergy Data Centers is a company with international ambitions and a green vision. There are no open vacancies at the moment; send your CV or questions to info@greenergydatacenters.com.

Visit

See the campus before you decide.

Alajaama tee 1, 76911 Hüüru, Harju County, Estonia. Twenty minutes from Tallinn city centre.

Book a site visit
The Greenergy Data Centers campus lit up on a winter night.