Dynamic analysis of material-product chains. An application to window frames

Environmental pressure associated with a specific economic service can originate from several stages in the process of production, use and disposal of products rendering that particular service. When alternative products are available to fulfil such a service, an interesting evaluation problem results, because generally such alternatives will differ in terms of materials composition. This means that different or even unique materials flows and environmental stress categories will be associated with each of them. This type of evaluation problem is studied here using a materials-product chain framework, in which links between materials and product flows, and between decision, market and physical processes can be considered. The term 'chain' refers to a sequence of activities, possibly including extraction, production, consumption, materials recycling and re-use of products, and treatment, incineration and dumping of waste. Chain management can then be considered as an overall policy strategy that takes explicit account of the sequential economic and physical linkages between these various activities. A dynamic simulation model is developed for studying the materials-product chain associated with the use of window frames in houses. This provides an interesting example of a durable good, the use of which has important long-run consequences for material flows. A number of environmental and economic indicators are considered in the modelling exercise so that a comparison and evaluation of policies and scenarios from a broad, integrative perspective is possible. Among other things, this allows for a ranking of instruments.