How to Select Relevant Indicators for Decision Making in Sustainability
Though many companies are increasingly assessing the impacts of their products, the focus is often only on climate change. Yet, decisions made solely on the basis of a carbon footprint may result in the shifting of burdens.
How to select relevant indicators for decision making in sustainability? For example, the combustion of biofuels compared to fossil fuels results in lower impacts on climate change, but larger impacts on land use and eutrophication, the latter caused by the use of fertilizers. For this reason, it is very important to consider all relevant environmental impacts when making product sustainability decisions.
Searching for impact relevance
State-of-the-art, comprehensive impact assessment methods such as ReCiPe cover about 20 indicators. The problem is identifying which impacts are the most relevant. Given the large number of impacts covered, each with a different unit, companies are faced with a very difficult task when making product development decisions. It is hard to know which impact is the most problematic, and therefore which should be resolved first.
Normalization: Maximizing change by minimizing indicators
In LCA, a common approach used to reduce the number of indicators and therefore more easily identify the most relevant impacts is known as “normalization”. Normalization allows for the impact of the product(s) under study to be compared to a reference situation. The reference commonly used is the average annual impact of a citizen of a certain region, for example Europe.
Unifying units under normalization
The advantages of using normalization is that all results are displayed in the same unit, e.g. capita·year, enabling the comparison between different indicators. This type of comparison provides insight into which environmental impacts are large in comparison to the reference situation. This comparison, however, does not provide insight into which environmental impacts are largest overall.
A solution for easier decision-making
There is a consensus that normalization is a good way to reduce the number of indicators, but different approaches using normalization can be applied. A couple of years ago, Gert Van Hoof, Maria Gausman, and Annie Weisbrod from Procter & Gamble and I from PRé started discussing the decision-making challenges of indicator selection in LCA. We reached a solution. The result of this collaboration was published in the International Journal of Life Cycle Assessment.
Senior Technical Consultant and Lead trainer