Data4 breaks ground on its mega data centre campus in Paiania

The approval covers a campus comprising three data centres (DC01, DC02 and DC03) on a 7.48-hectare site at 33 Agiou Louka Street in Paiania. The project will have a total installed capacity of 80 MW and has been designed to support large-scale cloud computing, data storage, artificial intelligence and telecommunications services.

The project is being developed by DATA4, one of Europe’s largest independent data centre operators. Backed by Brookfield, the French company has an established presence in France, Italy, Spain, Poland and Germany, and has now expanded into Greece.

The Paiania investment was announced in 2024 with an initial budget exceeding €300 million. According to the company’s management, the development forms part of DATA4’s €7 billion European investment programme through 2030.

From 15 MW to an 80 MW Campus

The ATH01–HERMES project does not start from scratch. The new environmental approval effectively authorises the expansion of the already licensed 15 MW DC01 facility, transforming the original project into a fully integrated data centre campus.

The development will comprise three two-storey buildings with underground facilities, equipped with advanced energy management systems, telecommunications infrastructure, data storage equipment and AI-ready infrastructure.

Power infrastructure is one of the project’s defining technical features. Plans include a 150 kV transmission substation operated by the Independent Power Transmission Operator (IPTO), a 5.5-kilometre underground transmission line, multiple high-voltage transformers and rooftop photovoltaic systems.

To ensure uninterrupted operations, the campus will also be equipped with 60 backup generators and 16 double-walled fuel storage tanks.

The location was carefully selected. DATA4 has secured a 7.5-hectare site within an industrial zone just 20 minutes from central Athens, offering access to critical power and telecommunications infrastructure. The campus has been designed to accommodate up to 90 MW of capacity, placing it among the largest data centre developments in the Greek market.

Greece’s geographical position also provides a significant strategic advantage. New subsea cable systems linking Europe with the Middle East, Asia and Africa are strengthening Athens’ role as a key regional data exchange hub. DATA4 expects the capacity of the Greek data centre market to more than double by the end of the decade as demand for cloud computing and AI infrastructure continues to grow rapidly.

A New Real Estate Asset Class

Beyond its technological significance, the investment underscores the transformation of data centres from specialised industrial facilities into a distinct real estate asset class.

Across mature European markets, data centres are increasingly attracting institutional capital alongside logistics assets and prime office developments. Their value is no longer determined solely by land or buildings, but by access to electricity, fibre-optic connectivity and interconnection capabilities.

This is precisely where Paiania’s competitive advantage lies. The area combines three of the digital economy’s scarcest resources: available land, robust power infrastructure and proximity to a major metropolitan centre.

With environmental approval now secured, the ATH01–HERMES project moves from the permitting phase into implementation. More broadly, it reflects Greece’s ambition to evolve from a consumer of digital services into a producer of critical digital infrastructure serving Southeastern Europe and the wider region.