Why depreciate material goods?
In our daily lives, we use many objects and appliances designed to last for several years: cars, refrigerators, computers, washing machines, etc. Their **manufacturing carbon footprint **is significant. According to existing methodologies, this carbon footprint can either be allocated entirely to the year of purchase or depreciated linearly over the lifetime of these objects.
The Nos Gestes Climat calculator applies a **depreciation logic **inspired by accounting:
The impact of an item is spread over several years, based on its estimated lifespan.
Depreciation for cars
**Cars **are treated differently.
- They are depreciated on a straight-line basis.
- Depreciation is calculated based on the number of kilometres travelled rather than their lifespan in years.
Straight-line depreciation for other assets
For all other equipment (household appliances, digital equipment, small tools, etc.), depreciation is **straight-line **and spread evenly over the estimated useful life in years.
| Type of asset | Estimated useful life | Annual charge |
|---|---|---|
| Laptop | 5 years | 1/5 per year |
| Television | 8 years | 1/8th per year |
| Tumble dryer | 10 years | 1/10th per year |
| Refrigerator | 12 years | 1/12th per year |
| This method provides a **more realistic representation **of the annual carbon footprint of your everyday objects. |
Why does this matter in your carbon footprint?
Depreciation allows you to:
- **Smooth out the environmental impact **of an asset over its useful life.
- **Avoid artificial peaks in emissions **in the year of purchase.
- Better reflect the actual share of your items in your annual footprint.
It also encourages people to **keep their assets for longer **and avoid premature replacement, particularly in highly polluting sectors such as electronics and automotive.
A constantly improving model
Lifespans and depreciation methods are regularly **reassessed **based on:
- User feedback
- Technological developments
- New impact studies
This ensures a **transparent, consistent and scalable model **that reflects the reality on the ground.
Conclusion – Making the invisible visible, sustainably
Depreciating assets in Nos Gestes Climat helps to avoid calculation biases and better link our objects to their real ecological cost. It is an essential tool for raising awareness of the impact of sustainable consumption.
To go further:
https://www.ge.ch/teaser/mon-climat/mon-climat
https://www.ge.ch/teaser/consomm-action
https://www.geneve.ch/themes/durabilite/acheter-facon-responsable