• FRA03 provides 7,680 square metres of IT space across three floors and six data halls
  • Phase 1 is complete, while Phase 2 must still be delivered before the full site is finished

The fact

German data-centre operator Maincubes has completed the first construction phase of FRA03 in Schwalbach am Taunus, near Frankfurt. Work began in the fourth quarter of 2024, and Phase 1 ended in June 2026. The company says customer capacity will be available from the third quarter. Construction of Phase 2 began in the third quarter of 2025 and is expected to finish in 2026 or 2027.

FRA03 is designed to provide 16MW of IT capacity and 7,680 square metres of IT space across three floors and six data halls. The site supports air and liquid cooling and is aimed at hyperscale and high-performance computing workloads. Maincubes says it will use renewable electricity and feed waste heat into a local heating network.

The assessment

Completing Phase 1 gives maincubes space that can begin accepting customers, but it does not mean the whole 16MW site has been delivered. The operator must commission the available halls, connect customer equipment and complete Phase 2 before FRA03 reaches its full design.

Customers therefore need capacity information at module level. They must know which halls are ready, how much power and cooling each can provide and when later space will become available. The same distinction applies to heat reuse: FRA03 can supply waste heat only when the data halls are carrying load and the connection to the local heating network is operating. For BTW readers, FRA03 is moving from construction into phased service. Customer handovers and commissioned megawatts will show how much usable capacity Phase 1 provides while maincubes finishes the rest of the site.

What to watch

Maincubes has not disclosed how much IT capacity will be available when customer service begins. Initial customer handovers, commissioned megawatts and the completion date for Phase 2 will show how quickly FRA03 progresses from its first finished module to the full 16MW design.