In Europe, the key data centre regions have been Frankfurt, London, Amsterdam, Paris and Dublin, known as the FLAP-D market. Frankfurt hosts the DE-CIX internet exchange point, London hosts a plethora of high-speed financial trading houses and Amsterdam has another exchange point(AMS-IX). Paris also sits as the heart of key interconnections and Dublin has benefitted from the presence of the American hyperscalers(Boonstra 2023). According to the real estate investor CBRE, London and Frankfurt account for approxi­mately half of total data centre supply in FLAP-D at the end of 2025, estimated to be 1.3 GW and 1.2 GW markets, respectively(CBRE 2025a). The market for European cloud capacity is highly satu­rated. High demand, as well as supply constraints, are demon strated by the vacancy rate remaining below 10 % in 2025(CBRE 2025a). The buildout of new data centres has currently been severely curtailed in the key locations due to considerations over energy and land use. Accord­ing to some commentators, 33 to 45 % of electricity in Frankfurt is spent on data centres, while in Dublin, esti­mates range from 64 % to 95  %(Gröger et al. 2025). This has halted data centre construction in some markets, leading to ­spillovers to other places(Madrid, Warsaw, Milan and Zurich)(CBRE 2025b) with more abundant energy, planning permits, land availability or ambient cooling to help control the costs of running the data centres(CBRE 2025c). AI infrastructure requires a wholly different size of data centre capex in terms of geography, energy and deployed capital (CBRE 2023). Geographically, the large AI data cen ­tres are built outside metropolitan areas and conventional cloud hotspots because of cheaper greenfield land, access to electricity and reduced local congestion. This has impli­cations for energy demand: while a 10 MW data centre was previously considered large and a 100 MW centre a hyper ­scale project, references to projected 1,000 MW(1 GW) sized projects are becoming commonplace. For example, Project Rainier by AWS, currently being built in Indiana to serve AWS AI workloads, is planned to be 2.2 GW when operational. The xAI Colossus data centre draws 150 MW of power and houses 100,000 AI chips 3 , in the range of AI chip clusters forecasted to be built under the EU´s Gigafactories initiative. At their limit, aspirational 3  The Colossus 2 is planned to draw 2 GW of power when ready. European cloud computing market vacancy rates in MW, 2016–2025(Q3, 2025) Figure 6 Percent 45  Forecast 40 35 30 25 1 20 15 4 6 2 5 10 3 5 0 2016 2017 1 Amsterdam 2018 2 Dublin 2019 2020 3 Frankfurt 2021 4 London 2022 2023 5 Paris 6 2024 2025 Secondary markets Source: CBRE, 2025b. Introduction 11