Embodied carbon emissions are the greenhouse-gas emissions produced before, between, and after a device’s use: manufacturing, transportation, and end-of-life processing. They exclude electricity consumed while the device operates. Mining materials, fossil-fuel-intensive manufacturing, global shipping, dismantling, and hazardous-material treatment all contribute. section 8.2.2 section 8.6
Use the metric to reason about hardware lifespan and software’s indirect environmental effects:
- Amortize the initial footprint by keeping devices in service longer through repair, reuse, or repurposing. section 8.2.2
- Distinguish embodied emissions from operational emissions caused by electricity consumption during use. section 8.2.2 section 8.6
- Account for software-driven technological obsolescence, which can retire functioning hardware when support ends or requirements outgrow its capabilities. section 8.2.2 section 8.6
- Treat embodied carbon as an estimate rather than a directly measurable number when using Software Carbon Intensity, which combines it with electricity use and regional carbon intensity. section 8.5.1
Smartphone lifespan
A smartphone may generate roughly 75% of its total carbon emissions before it is turned on. Extending its use from an average of about three years toward its potential seven-year lifespan spreads that embodied cost across more years of service. Servers typically show a smaller embodied share—about 30%–40%—because ongoing electricity consumption dominates over five to seven years. section 8.2.2
