Lower Use of Material & Energy

Nanotechnology offers two ways to reduce material and energy use. First, nanomaterials are generally more active than bulk materials, and so either less material is required or the abilities of that material (e.g. insulation) are greatly enhanced. Second, more abundant materials can often be converted into excellent substitutes for rare materials through the application of nanotechnology (e.g. replacing platinum in catalytic convertors with nanostructured metal oxides).

These new applications can often be more energy efficient, both in manufacturing and in ultimate use. However, there needs to be a life cycle analysis approach to this to determine whether the new application is sustainable and whether it will actually reduce or increase the burden on the environment. This means determining the total material and energy use from product development through manufacture, use, and final recycling or disposal. For example, indium is used extensively in LCD screens and in new solar cell technologies. However it is only ever used in small amounts: a laptop screen for example contains 50 milligrams of indium. Indium is only mined in 6 places around the world and at only 350 tonnes each year; so it is clear that there is only a limited supply (e.g. compared to iron). What happens when it runs out? How can indium be recycled effectively when it is so widely dispersed? There is obviously a real need to develop new nanomaterials that can take the place of materials such as indium, and that are more abundant. In the case of indium, nanostructured zinc oxide shows great promise, at least for certain applications.