A single product (the small cube) travels a cradle-to-grave line: raw-material extraction, manufacturing, packaging, transport, use, and end-of-life. Each station emits CO2e (visualized as rising particles) at a rate set by its own emission factor; the factor for manufacturing depends on the electricity grid's renewable share, the factor for transport depends on distance and mode (ship < truck < air per tonne-km), and end-of-life emissions are reduced — and partly avoided — the higher the recycling rate. Every time the product completes one full pass, its accumulated footprint is logged as one finished unit and a fresh product starts from raw materials.
stage_kgCO2e = base(stage) × factor(stage, sliders)
factor(mfg) = 1 − 0.75 × renewable_share
factor(trans) = (distance/1000) × mode_intensity
factor(eol) = 1 − 0.8 × recycling_rate
total = Σ stage_kgCO2e (Life Cycle Assessment, cradle-to-grave)
- Transport distance — how far the product travels from factory to point of use; longer supply chains scale the transport slice linearly.
- Transport mode — ship, truck or air freight, each with a very different CO2 per tonne-km (air is roughly an order of magnitude worse than ship for the same distance).
- Grid renewables — the share of manufacturing electricity coming from low-carbon sources; this is the single biggest lever on the production slice.
- Recycling rate — the share of the product recovered at end-of-life instead of landfilled or incinerated, cutting disposal emissions and avoiding some virgin-material extraction next cycle.
Real-world relevance: this mirrors how an Environmental Product Declaration (EPD) breaks a product's footprint down by lifecycle stage under LCA methodology — useful because the biggest lever (manufacturing energy vs. transport vs. end-of-life) is different for every product category.