Where the Load Sits: data-centre electricity by country

Two metered countries, and models everywhere else

Almost nobody measures how much electricity data centres use. Ireland's Central Statistics Office does, through a survey of metered supply points, and the Dutch statistics office CBS publishes a figure on comparable terms. Every other region on this chart is an estimate built by its author from floor space, installed server capacity, utilisation assumptions and an overhead factor for cooling and power conversion. Solid bars mark the metered figures and hatched bars the modelled ones, because the difference between them is larger than most of the differences between countries.

Definitions vary as much as methods. Some authors count any room with servers in it, including the cupboard in an office; others count only purpose-built facilities above a size threshold; some include telecommunications exchanges, and some count cryptocurrency mining. A country can therefore appear high because its data centres are large or because its statisticians draw a wide boundary, and the source note on each bar is the only way to tell.

The years differ too. Each institution publishes on its own schedule, so one region's latest available year can be several years behind another's, and the year is printed in every label. In a sector growing this quickly, comparing a recent figure with an older one understates the older region by a margin that grows with the gap.

The dots carry the most transferable information. A share of national electricity demand puts a small country with a concentrated industry and a large country with a dispersed one on the same scale, and it is the figure that matters to a grid operator planning connections. Ireland stands out on that measure for reasons of geography, tax and timing. Its statistical definition is also one of the most complete, which raises its figure.