Six areas of methodological debate on attributional life cycle assessment

Abstract

There is a general agreement in the LCA community that there are two types of LCAs: attributional and consequential. There have been numerous discussions about the pros and cons of the two approaches and on differences in methodology, in particular about methods that can be used in consequential LCA. There are, however, methodological aspects of attributional LCA and how it can be used that need further attention. This article discusses six areas of debate and potential misunderstandings concerning attributional LCA. These are: 1) LCA results of all the products in the world should add up to the total environmental impact of the world, sometimes referred to as the 100 % rule. 2) Attributional LCA is less relevant than consequential LCA. 3) System expansion, and/or substitution, cannot be used in attributional LCA. 4) Attributional LCA leads to more truncation errors than consequential LCA does. 5) There is a clear connection between the goal and questions of an LCA and the choice of attributional or consequential LCA. 6) There is a clear boundary between attributional and consequential LCA. In the article, these statements are discussed, and it is argued that they are either misunderstandings or sometimes incorrect.