Data centres used to be built from the ground up on site, over two to three years. AI has changed that. More and more of the building is now made in a factory, shipped as modules and connected on site, because AI operators need capacity faster than traditional construction can deliver it.
For the people who build, commission and run these facilities, that shift changes where the work happens and which skills are in demand.
What is a prefabricated data centre?
A prefabricated, or modular, data centre is built from large modules made in a factory instead of being assembled piece by piece on site. Typical modules include:
- Power modules: switchgear, UPS and distribution, tested before they leave the factory
- Cooling modules: chillers, pumps and the liquid cooling plant that AI racks need
- IT modules: white space with racks, containment and controls already in place
The modules are built while groundworks, permits and grid applications run in parallel. On site, the job becomes connecting, integrating and commissioning them.
Why is data centre construction moving into the factory?
It comes down to two things: density and speed.
- Density. The newest GPU racks for AI draw around 120 kW or more each, while a conventional enterprise rack draws a fraction of that. Most existing buildings were never designed for that load.
- Speed. A traditional build takes 24 to 36 months to design, permit and deliver, according to DCD. Some prefabricated AI modules can be delivered in three to nine months, Computer Weekly reports.
This is no longer a niche method. McKinsey estimates that prefabricated and modular work makes up 40 to 60% of a typical data centre project, and that standardised prefab can cut delivery timelines by up to half.
How big is the modular data centre market in Europe?
According to Fortune Business Insights, Europe's modular data centre market is worth around 9.6 billion US dollars in 2026 and is growing by about 14.6% a year. The main drivers are:
- cloud and AI workloads
- colocation demand
- data sovereignty, with more data kept inside Europe
Globally, the same research puts the market near 35 billion dollars this year, rising to about 117 billion by 2034.
Does prefabrication solve the grid problem?
No. A module can be ready in months, but a site still cannot run without power, and the grid connection is the slowest part of many European projects.
- Ireland. New data centre connections in the Dublin area were effectively on hold for years. In December 2025 the Commission for Regulation of Utilities (CRU) set out a new route: new data centres can connect if they bring generation or storage that matches their demand.
- The Netherlands. Grid congestion means many large users face long waits for a new or heavier connection.
What prefabrication does change is what a project can do while it waits. Prefabricated power modules and on site generation let a site energise on its own schedule instead of the grid operator's. That is why power modules have become as important as the IT modules themselves.
Why does the cooling arrive ready built?
AI density makes liquid cooling a necessity, and liquid cooling is hard to retrofit on site. Modules arrive with the cooling plant already integrated and tested, which makes installation faster and more predictable.
Regulation pushes in the same direction, especially in Germany:
- Under the German Energy Efficiency Act (EnEfG), data centres that start operating from 1 July 2026 must reach a PUE of 1.2 or better and reuse at least 10% of their waste heat.
- At EU level, the Energy Efficiency Directive requires larger data centres to report their energy performance every year.
Factory built and tested modules make it easier to hit speed and efficiency targets at the same time, instead of trading one against the other.
What does this mean for data centre jobs?
The work is splitting in two.
In the factory
- module engineering and design
- assembly, testing and QA
- factory acceptance testing
- logistics for moving large modules across Europe
On site
- shorter, more intense installation windows
- integration of power, cooling and IT modules
- commissioning and site acceptance testing, often against a fixed date
Manufacturing discipline combined with data centre knowledge is now a strong profile. On site, the premium goes to people who can take a module, integrate it and commission it fast, without the long runway a traditional build used to allow.
One honest caution. Factory teams often see only their own part of the system. The engineers and project managers who understand the whole build, from factory floor to handover, are the ones who keep these projects reliable.
The short version
AI needs capacity faster than traditional construction can deliver, so more of the data centre is now built in a factory and finished on site. For the people who build and commission these facilities, the work is moving into production halls and into shorter, sharper windows on site.
DC People places engineers, commissioning specialists and project managers on data centre builds across Europe and the Nordics. Browse our open vacancies, or read where the next wave of projects is heading in Helsinki joins EMEA's data centre Powerhouse markets.
Sources
- DCD: Modular by necessity: the shift from site to factory and traditional build timelines
- Computer Weekly: Prefabricated modular datacentres: delivery times for AI modules
- Fortune Business Insights: Modular data center market: European and global market size
- Moduledge: How to build an AI data center: McKinsey prefab share and AI rack densities
- Mason Hayes & Curran: CRU sets out new rules for data centre connections: Ireland's connection policy
- White & Case: Data center requirements under the German Energy Efficiency Act: PUE and heat reuse rules in Germany
Frequently Asked Questions
What is a prefabricated data centre?
A prefabricated or modular data centre is built from large modules made in a factory, such as power, cooling and IT modules. They are tested before they leave the factory, shipped to site and connected there, instead of being assembled piece by piece on site.
How much faster is a modular data centre build?
A traditional data centre usually takes 24 to 36 months to design, permit and build. Some prefabricated AI modules can be delivered in three to nine months, because the factory work runs in parallel with groundworks, permits and grid applications. The grid connection still decides when a site can go live.
Does prefabrication solve grid connection delays?
No. Modules can be ready in months, but a site cannot run without power. What prefabrication does change is what a project can do while it waits, for example installing prefabricated power modules and on site generation so the site can energise on its own schedule.
Which jobs are growing in modular data centre construction?
In the factory: module engineering, assembly, testing and QA, factory acceptance testing and logistics for large modules. On site: integration of power, cooling and IT modules, commissioning and site acceptance testing, usually in shorter and more intense project windows.
What are Germany's efficiency rules for new data centres?
Under the German Energy Efficiency Act (EnEfG), data centres that start operating from 1 July 2026 must reach a PUE of 1.2 or better and reuse at least 10% of their waste heat.
Where can I find data centre jobs on modular projects?
DC People places engineers, commissioning specialists and project managers on data centre projects across Europe and the Nordics. Current openings are listed on careers.dc-people.com.
