🌏 PLANET Catering Impact Estimator

Methodology & sources

Food emissions are estimated on a cradle-to-gate basis. We multiply a per-100 g factor (kg CO₂e / 100 g) by the (adjusted) portion size to get per-meal emissions, then scale by the number of meals. Diet groups: Beef/Lamb; Other meat & fish; Vegetarian; Vegan.

TRACE provides benchmark portion weights (e.g., sit-down mains 412 g; bowl food 300 g; buffet 600 g), which drive the default portion selector here. This tool keeps those benchmarks but lets you adjust portion size ±25% to explore under‑/over‑serving effects.

• TRACE methodology (Food & Beverages module; portion weights; cradle-to-gate factors): weareisla.co.uk/trace
• Our World in Data overview of Poore & Nemecek (2018) meta-analysis (alternative preset): ourworldindata.org/environmental-impacts-of-food

Baseline splits (90/10, 70/30, 50/50) are indicative only. Use a custom baseline that reflects your event.

Real-world analogies

To help producers visualise the impact of shifting menus, the estimator converts total emissions savings vs baseline into simple analogies:

• Driving: ~0.192 kg CO₂e per km (average petrol car). Total CO₂e savings (kg) ÷ 0.192 → “km of driving avoided”.
• Trees: ~25 kg CO₂e per mature tree per year. Total CO₂e savings (kg) ÷ 25 → “equivalent number of trees absorbing that CO₂ in a year”.
• Analogies are based on emissions saved vs the selected baseline menu, not the absolute footprint of your event. If the scenario is more carbon-intensive than the baseline, savings are treated as zero and analogies are shown as 0.

These figures are indicative only and intended for comparison and storytelling – not for precise carbon accounting or offsetting claims.