Why do some resources have a negative CEII?
If a resource is not consumed but produced in the process, it is assigned a negative impact.
Definitions
PI - Pollution Index. Indication of the amount and severity of the pollution generated during the life cycle of an item. The higher number, the more pollution.
DI - Depletion Index. Indication of the amount of resources used during production and disposal of an item. The higher number, the more resources are used (and the less sustainable the product is).
EI - Entropy Index. - Indication of the amount of energy wasted during the life cycle of an item. The higher number, the more energy is wasted.
CEII - Composite Environmental Impact Index. Indication of the item's impact on the environment, taking into account the resources used and the pollution generated during production, use, and disposal of the item. The higher number, the higher impact.
