Scope 1, 2 and 3 Emissions

<p>The Greenhouse Gas (GHG) Protocol defines three scopes for categorising emissions. Scope 1 covers direct emissions from sources owned or controlled by an organisation — diesel generators, refrigerant leaks from cooling systems, on-site gas use. Scope 2 covers indirect emissions from purchased electricity, heat and cooling — for a data centre, this is primarily the carbon intensity of grid electricity consumed. Scope 3 covers all other indirect emissions in the value chain — embodied carbon in equipment (servers, cooling plant), employee travel, waste, upstream fuel extraction.</p><p>For data centres, Scope 2 is typically dominant. CUE measures Scope 2 carbon attributable to IT load. Scope 3 — particularly the embodied carbon in server hardware — is increasingly recognised as material, with server manufacturing estimated to account for 50–80% of a server's lifetime carbon footprint. The Science Based Targets initiative (SBTi) requires organisations to address all three scopes in their net-zero commitments.</p>