IT hardware carbon calculator

In two parts, and they must not be mixed. The operational part is arithmetic: annual kWh × the emissions factor. For UK electricity in 2026 that is 0.13096 kg CO₂e per kWh for generation (scope 2) plus 0.01299 kg CO₂e per kWh for transmission and distribution losses (scope 3), both published by DESNZ. The manufacturing part comes from the vendor's product carbon footprint document, and it is an estimate with a large uncertainty. This tool computes the first exactly, from the power-supply configuration in each model's own technical document, and asks you for the second.

No, and this is the mistake that makes most IT carbon reporting wrong. Dell's PCF documents state a TOTAL LIFECYCLE figure — materials, manufacturing, distribution, use and end-of-life — modelled with MIT's PAIA tool on Dell's own assumptions about product lifetime, use location and annual energy. Treating that whole number as "the carbon of building the server" double-counts the use phase you are also calculating yourself. The published uncertainty is close to ±100% of the value, which Dell states plainly and most citations of it do not.

It depends on the payback, and the answer is not always "replace". New hardware carries a one-off manufacturing impact; it earns that back only through lower operational emissions. If the replacement saves a few tonnes a year and its manufacture cost tens of tonnes, the break-even can be longer than the kit will be in service — in which case extending support on what you have is the lower-carbon choice. This tool shows the crossover year rather than assuming the refresh wins.

SECR requires UK energy use and the associated greenhouse gas emissions, using an emissions factor, with the methodology stated. The operational figures here are calculated on the UK government's published 2026 conversion factors and split into scope 2 (generation) and scope 3 (transmission and distribution), which is the split most reports need. If you buy a renewable tariff, your market-based scope 2 figure will differ from the location-based figure shown here — both have a place, and the guidance expects you to say which you used.

Because the electricity meter does not stop at the server. Power Usage Effectiveness is total facility energy divided by IT energy, so a room at PUE 1.5 burns half as much again on cooling and losses as it does on computing. Setting PUE to 1.0 gives the IT load alone, which is the right comparison for a colocation contract that bills IT power separately; leave it at 1.3–1.6 for a typical UK server room.

The reference figures are Dell's own published product carbon footprint documents: Dell PowerEdge R740 (2U rack) at 8,640 kg CO₂e (±8,480), Dell PowerEdge R640 (1U rack) at 7,730 kg CO₂e (±7,900), Dell PowerEdge T640 (tower) at 8,000 kg CO₂e (±8,130) — each on a 4-year life with EU use and a stated annual energy assumption. Current-generation server PCFs are issued on request rather than published, and HPE and Lenovo publish their own product declarations, so where you can get the document for your exact model you should use that number instead.