ABSTRACT
Sustainability as defined by the Brundtland commission depends on many factors connected to product development. Materials choice, resource allocation, upgrading, and recycling have strong links to the product structure. Product structures, as means to achieve sustainable products, are the core ingredients in this chapter. Materials are to some extent a limited resource, and metals as an example have been recycled for a very long time since recycling is often cheaper than mining and refining. However, benefits from materials circulation is not obvious, since humankind has been very inventive in substituting different materials. Resources like energy, fresh water, and air are limited and industrial activities, and the products themselves have an impact on these resources that cannot be neglected. The biological circulation (“ecocycling”) in nature, where water, coal, and oxygen circulate, is the basis for life on earth, and it is also an ideal model for the industrial ecology. Upgrading or recycling depends on many factors and is not always the best thing to do. What is the right thing to do under certain conditions can be totally wrong under other circumstances, and suboptimizations must be avoided.
