Data center campus

A data center campus is a group of data center buildings on a single plot, often around one shared utility substation, so that one loss event can hit several of them at once. On March 10, 2021, in Strasbourg, the fire that started in SBG2 destroyed that building, damaged part of SBG1 and forced the shutdown of SBG3 and SBG4, which had not burned but shared the same site and the same power supply. OVHcloud sold those buildings as separate facilities; the fire treated them as one risk. Besides the substation, the buildings share roads and often a fuel reserve. Developers save on grid connection and construction cost, and hyperscalers now build campuses of several hundred MW (megawatts). The underwriter has to decide what a single loss is. If the policy covers the whole site with a per-occurrence limit, a fire that spreads from one building to the next, or a flood that drowns the shared substation, uses up the entire limit in one go. Hence per-building sublimits, required fire separation distances between buildings, and the question of availability zones: a cloud provider that places several zones on the same campus advertises redundancy that the first site-wide loss wipes out. Accumulation is then measured on the footprint and the substation rather than the street address. One caveat: a well-designed campus, with spaced buildings, dual utility feeds and separate fuel reserves, can keep its maximum foreseeable loss close to that of a single building.