Metric relating a data centre's CO2 emissions to the energy used by its IT equipment.
CUE relates a data centre's carbon dioxide emissions to the energy used by its IT equipment, expressed in kilograms of CO2 per kilowatt-hour. Unlike PUE which measures raw energy efficiency, CUE incorporates the carbon intensity of the electricity used: two centres with identical PUE can show very different CUE depending on whether their grid is coal-powered or nuclear and renewables. The metric directly links digital infrastructure to sustainable insurance and climate-aligned underwriting issues. For an operator seeking a low CUE, the choice of geographic location, access to a decarbonised grid and recourse to green power purchase agreements become strategic. CUE materialises the tension between the explosion in energy demand driven by artificial intelligence and operators' net zero commitments.
A data centre on a heavily hydro-powered Nordic grid shows a far lower CUE than an equivalent site on a coal-fired grid, at equal PUE.
CUE, efficacité d'utilisation carbone, carbon usage effectiveness