It is possible to wonder where some people got their education – even, if they did. For example, it is being seriously suggested that we’d all save money if only we built ships out of aluminium instead of steel. Aluminium costs more than steel – some four to five times more in fact. So quite how this will save money isn’t obvious.
But here it is, here’s the assertion:
Because of the wide availability of cheap (and often dirty) fuel, shipping has traditionally been wasteful. Most merchant ships are made of heavy steel rather than lighter aluminium,
Well, the basic cost of aluminium is that several times that of steel. So, obviously, it’s not all that likely that the fuel savings from the lighter weight are going to be worth it.
We’ve even an interesting test of the proposition – if it were then more ships would be built of aluminium in order to gain the fuel savings, wouldn’t they?
But it’s worse than this for of course it is. The usual mistake of thinking only about emissions from operation, rather than total system usage, is being made.
Each tonne of aluminium – it’s a rule of thumb but a useful one – incorporates $900 of energy. That’s just what it costs in order to turn aluminium oxide into aluminium. Steel, given its lower price in total, quite obviously incorporates less energy than this.
So, the suggestion is that we should be using more energy in our system in order to save energy then, is it?
And people wonder why no one in the metals or mining world takes a blind bit of notice of the environmentalists, do they?