2.18 Summary

We have seen in this chapter that materials are used for everything we do, that use of materials has increased steadily over time and the trends are set to continue to increase.  The impact of this material use is in the embodied energy of the materials, the waste created by them and the depleting resources seen as a result.

It has been shown that engineers can reduce the unsustainable nature of material production by having a holistic view of materials from the outset, and incorporating sustainability into produce design.  This can be done by reducing consumption through longer life design, design for re-use at the end of life, and design for recyclability. We have also considered designing to incorporate sustainable materials as substitutes to traditional materials.

It is clear that more needs to be done in the field of sustainable materials, reducing the energy in manufacture, reducing the amount of materials used and research into natural substitutes.  As demonstrated in most cases, the leading impetus is the business case, and usually the cheapest option will be the driving force.  In the same way, it is the scale of consumption driving by thirst for profit through continuous sales that is the cause of the impact of material use, and consumers only pay for the end product – they don't take account for any “externalities” such as social or environmental harm.  It is this deeper issue that needs to be addressed in society to implement a more sustainable trajectory.