Avoided burden


Avoided burden is an approach used in life-cycle assessment, especially in the context of allocating environmental burden in the presence of recycling or reuse. When determining the overall environmental impact of a product, the product is given "credit" for the potential recycled material included. For instance, PET bottles may be given environmental credit for the PET they contain, as this material will eventually be recycled back into further PET products. This credit is termed "avoided burden" because it refers to the impact of virgin material production that is avoided by the use of recycled material.

Material displacement

The extent to which recycled material displaces production of virgin material of a similar or different type is the subject of current research. In case studies, practitioners typically utilize heuristic, arbitrary rules, such as assigning 100%, 50%, or 0% displacement of virgin material by recycled material. However, accurate information on the displacement rates of various materials is largely unknown. This information is important to LCA practitioners, as it can often tip the balance between two compared alternative products or materials.

Calculation

Although the calculation of avoided burden is not without some degree of subjectivity, it is usually calculated as follows: