Spain wants data centres on 80% renewables every hour, or no grid connection

Spain has drafted a decree that would require new data centres to source at least 80% of their electricity from renewables in every hour of operation, with loss of grid connection as the penalty for failing to comply.

It is a markedly firmer position than the one Brussels has taken, having previously told Big Tech to align data centres with climate goals without much in the way of a mechanism, and it lands in a continent where Denmark has already paused grid connections outright.

The hourly requirement is the technically demanding part. Annual matching, where an operator buys enough renewable energy over a year to offset consumption, is comparatively easy, whereas hourly matching means the power has to be there when the servers are drawing it.

New capacity comes with an additional obligation. Every new megawatt requires matching renewable installations to be in place within 18 months before operation, achieved either through contracts or by building locally.

That effectively makes each data centre responsible for commissioning the generation it consumes, which is the same causer-pays logic Australia has been trying to legislate. The difference is that Spain has a simpler constitutional route to imposing it.

Whether the grid can support it is a separate question from whether operators can. Hourly matching depends on storage, interconnection, and generation profiles that vary by region, and a rule written nationally has to work in places where the sun sets at the same time everywhere.

Operators would have to be established in the EU, with all data and metadata remaining within European borders, access from third countries controlled, and heightened protections applied to data belonging to public bodies or touching national security.

That is a sovereignty measure wearing an environmental decree’s clothing. Requiring EU establishment and European data residency reaches directly at the American hyperscalers who have built much of Spain’s recent capacity.

It is also a rare instance of a member state legislating data residency more tightly than EU law requires. GDPR restricts transfers rather than storage, and a flat requirement to keep data and metadata in Europe goes further than the bloc has been willing to.

Water and efficiency standards would match the highest sustainability label the EU is currently developing for the sector. Spain’s water position makes that unavoidable politically, given how much of the country has spent recent summers under drought restrictions.

Scope is drawn at facilities above one megawatt that are not yet connected to the grid. Projects already in the permitting process would get six months to comply or forfeit their connection rights, without compensation.

Six months is not long for a project financed on assumptions about power costs. Developers who priced their models on annual renewable matching would have to redo the arithmetic or walk away from a queue position that took years to obtain.

Spain has been one of Europe’s fastest-growing data centre markets precisely because it has cheap renewables and available land, which is the combination developers have been chasing as capacity moves away from the traditional big five markets.

Government sources frame the decree as a way of choosing the best and most efficient projects rather than taking whatever arrives.

The risk in that framing is that developers have options. Capacity that cannot clear Spain’s bar can go to Portugal, Italy, or the Nordics, and research has already warned that Europe’s sovereign AI ambitions could stall on data centre constraints rather than on model quality.

Madrid is betting that the projects will come anyway. Spain has what the sector actually needs, which is sunshine, wind, land, and interconnection capacity, and a government that believes it holds a scarce asset can afford to attach conditions to it.

The decree opens for public consultation this week, and the reporting is sourced rather than official, so the text may soften before it is adopted. Consultation is where the industry gets to argue, and the hourly matching requirement is the clause it will argue about.