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Can ... be recycled?
What's ... made from?
Where does ... come from?
3a Irina, an ecological adviser, is talking to a group of engineers on a training course about
environmentally friendly design. In pairs, discuss the ideas from her slide and give some
examples.
►2.1 Read an extract from the talk and compare your ideas with what Irina says. What
example does she use to illustrate her main point?

Irina: The only way to assess the environmental impact of a given material properly is to carry
out an environmental audit and analyse the total impact of that material on the environment.
I emphasise total impact because it’s all too easy to judge materials and products on single
aspects of their ecological impact. As an example, if we compare traditional and energysaving
light bulbs it’s tempting to say energysaving ones are better because they consume less energy.
In fact, that’s only part of the picture. That’s just the in-use phase. You also need to consider the
pre-use phase - in other words, the environmental impact of mining the materials used to make
the bulbs, of transporting those materials to the factory, of manufacturing them etcetera. Then
there’s the post-use phase. How easy is it to recycle spent bulbs? And when you start to consider
all of these factors, suddenly the comparison between classic bulbs and their energy-saving
equivalents becomes much less clear-cut. Some of the materials used in energy-saving lights are
problematic from an environmental standpoint, both in terms of acquiring them and recycling
them. So the point is, it’s essential to look at the whole picture. And doing that can be quite a
complex task, as we’ll see later on.

►2.2 Irina asks the engineers to do a simplified environmental audit. Their task is to
compare steel and aluminium car bodywork from an ecological perspective. Read Sophia
and Pete, two of the engineers, discussing the topic and make notes of their ideas.

Sophia: OK, so steel bodywork versus aluminium bodywork.
Pete: What about pre-use, then?
Sophia: Well, I think it takes a lot of energy to produce aluminium, compared with steel, because
aluminium's made by electrolysis.
Pete: Yeah. So steel's better, presumably.
Sophia: I think so, yeah. But, hang on a minute, with aluminium, it depends how much is derived
from ore, and how much is recovered from recycled material. As far as I know, recycling
aluminium takes less energy. So I'm not really sure.
Pete: Presumably, it’ll be mixed, won’t it? For a given batch, there'll be so much new material,
and so much recycled material.
Sophia: Probably, yeah. OK, so that needs to be researched, then.
Pete: Is car bodywork galvanised when it's made from steel?
Sophia: Urn ... good question. I'm not sure.
Pete: If it is, if it has to be coated with zinc, then that would take extra material and extra
energy. So that’s an important consideration.
Sophia: Mm, true. OK, so that's another question to note.
Pete: Then there’s the energy consumed when they're transporting bulk metal to the car plant.
Sophia: Presumably aluminium takes less energy to transport, being lighter.
Pete: I'd say so, yeah.
Sophia: OK. What about manufacturing?
Pete: Well, aluminium would be lighter to handle, wouldn’t it? It probably takes less energy to
cut, as well.
Sophia: Yeah. Not sure whether it takes less energy to weld, compared with steel.

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