What is that worth
in AI images?

There is no universal energy cost. The central 2.9 Wh estimate follows the mean measured by Luccioni, Jernite & Strubell across image-generation models. We use 0.7 to 11.5 Wh to expose variation from efficient small models through the study’s high observed result. Inference only; hardware, resolution, steps, batching and data-centre overhead can change real use.

Watts describe power. Watt-hours describe energy over time. One kWh equals 1,000 Wh. Carbon is calculated separately: energy × 143.95 gCO₂e/kWh, the 2026 UK grid generation plus transmission/distribution factor. The same image on another grid can have very different emissions.

Simple mode estimates distance at 800 km per flight-hour. Because the calculator does not know the route, it automatically uses 3,700 km as a transparent distance-only proxy for short or long haul. Official UK factors classify haul by destination region, so this is an approximation. Government passenger-km factors include an 8% distance uplift. Cabin class changes passenger allocation. The optional radiative-forcing variant represents additional non-CO₂ effects; UK guidance uses a 1.9 multiplier while noting substantial scientific uncertainty.

Cars use 2026 average-size UK factors and are divided by passengers entered. Public transport is already expressed per passenger-km. EV carbon follows the UK grid; the energy view uses 0.205 kWh/km. Actual vehicle, load, route, driving and occupancy matter.

Electric heat is compared by input electricity. Gas uses 0.18231 kgCO₂e/kWh (gross calorific value). Heat-pump output is contextualised with an illustrative coefficient of performance of 3.2; weather and system design alter real performance.