Integration des criteres de conception et de l'analyse de cycle de vie simplifiee pour l'ecoconception de produits a usage unique

Nowadays, several available environmental assessment methodologies allow the inclusion of life cycle aspects during the product development process. This practice is commonly called ecodesign. Among them, Life Cycle Analysis (LCA) plays an important role once it enables the evaluation of a product through its whole life, from cradle to gate, providing a comprehensive environmental profile. LCA is an methodological framework regulated by ISO standards which uses natural science based modeling, describing cause-effect relationships, to quantify the potential environmental impacts of a product.;The identification of hot spots can be a starting point to provide simple information to the product designer, considering they help to ascertain opportunities in the environmental point of view, without the need to follow a rigid ecodesign approach. Thereby, the product designer can remain creative, while having access to environmental information. Furthermore, the identification of hot spots avoids product design options that offer little environmental improvement because they do not target the key elements of the life cycle of the product.;Therefore, this research aims the identification of hot spots through several streamlined LCA approaches. In a context of single-use products improvement, it is important to take into account not only the environmental impacts but also the product design criteria which comply with users' expectations. This project will therefore emphasize the environmental hot spots in relationship with the product design criteria.;The research project objectives can be separated into two distinct ones. First, to consider the possibilities of simplifying LCA, thereby reducing the time and effort required to conduct a LCA study. And, second, to develop a matrix (called LCA-functional) to associate the LCA results with the design criteria, the so-called functionalities of the products.;However, other simplified approaches have been developed in order to reduce the time and effort associated with detailed LCA studies. These approaches, called simplified or streamlined LCA, may be qualitative or quantitative, depending on the required data for their implementation and the methods used to assess the environmental aspects or impacts. Such as detailed LCA, simplified LCA can be used to identify hot spots of a product. Under this project, the term hot spots designate the life cycle aspects or the elements of the product (e.g. product components) which significantly contribute to one of the environmental categories evaluated.;In this project, a LCA on a single-use consumer product was compared to three other streamlined LCA methods: I1) Environmentally Responsible Product Assessment (ERPA), I2) Typological Environmental Analysis (TEA), both qualitative methodologies based on environmental rules of thumb and expert judgment, and I3) Material, Energy, Chemicals and Others (MECO), which is based on inventory data. Despite the fact that TEA and ERPA methods are easier to be executed, their application revealed that the data and the environmental rules used are too generic, which can be problematic in the case of a consumer designed single-use products. Results also showed that for an equivalent time and effort invested for the MECO method, LCA is the most reliable option (up to the environmental impacts using indicator based on cause-effect chain) to identify product hot spots.;Then, a matrix-based approach was developed to implement the LCA results (i.e. the environmental profile) into the design criteria (i.e. the functional profile). Two LCA-functional matrices have been developed. The first one assesses environmental aspects and the second evaluates the product components. The results highlight the relationships between quantitative LCA results and qualitative information on product specifications. This leads to a more relevant identification of environmental and functional "hot spots". Both matrices were applied to the case of an absorbent single-use product to show the applicability of the approach as a tool for ecoredesign.