Use-phase carbon footprint

The use-phase carbon footprint represents the GHG emissions generated during the utilization phase of a product or asset, excluding manufacturing and end-of-life. It is especially relevant for goods with prolonged energy consumption, such as household appliances, vehicles, or buildings.

Main components

- Energy consumption: electricity, fuels, or heat during operation.

- Maintenance: replacement of components and spare materials.

- Operational inputs: hot water, cleaning chemicals, lubricants.

Calculation

- Determine usage patterns: hours/year, service intensity.

- Measure or estimate consumption: kWh, liters of fuel.

- Apply emission factors: local electricity mix, IPCC values for fuels.

- Multiply by projected service life (years).

Reduction strategies

- Energy efficiency: high-efficiency motors, insulation, LED.

- On-site renewable energy: solar self-consumption, heat pumps.

- Behavioral programs: standby modes, efficient driving.

Indicators

- kg CO₂e/year of operation.

- kg CO₂e per service unit (e.g., wash cycle, km traveled).

- % reduction vs. benchmark (Energy Star, EU Ecodesign).

Relation to other footprints

- Complements embodied carbon to obtain total carbon footprint.

- Essential in product decarbonization and efficiency labeling.

Addressing the use-phase carbon footprint is crucial for energy-intensive products, enabling significant reductions throughout their life cycle and improving the user’s total cost of ownership.