Oct 2009

The air we breathe

Ladies and gentlemen, the future.


The Airpod, air-powered car.

That air stuff… it’s great when you think about it. A ubiquitous, but entirely unobtrusive mixture of gases that’s wrapped around our planet several miles deep and provides fuel for many of the processes that occur within our body. It isn’t so much “easily accessible” as it is “impossible not to access” under normal circumstances.

Now before anyone looks at that strange little car and starts thinking either (a) that compressed air is the solution to our energy crisis, or (b) that I’m suggesting compressed air is the solution to our energy crisis, let me please request you stop thinking it. Because it’s not. And I’m not.

What I am suggesting, however, is that compressed air is a far better energy-carrier than batteries (or hydrogen fuel cells).

Let me qualify that statement.

Firstly, I’m not really talking about cars here. I still view the personal car as unsustainable, though there’s no reason compressed-air buses couldn’t be part of a future public transport system.

And secondly, I’m not speaking specifically about the energy-efficiency of compressed air Vs batteries.

What I am suggesting is that a wind-turbine powering your home / apartment building / housing estate (scale up as required) could be connected to an air-compressor during off-peak hours. Then when it’s calm and the turbine isn’t moving (or the sun isn’t shining, if solar panels are your primary generator) the compressed air can be used to produce electricity. It beats almost every other energy system I can think of hands down in the sustainability stakes. As well as the sheer elegance of the idea.

See the trouble with batteries is that they’re pretty short-lived, all things considered. They need to be replaced every few years and disposing of the old ones often involves dealing with nasty chemicals. With a compressed air system, on the other hand, you need a machine-shop and a bit of know-how (or the phone-number of someone with a machine-shop and a bit of know-how… hint: see the Yellow Pages under ‘Mechanic’) and you’ve got something that’ll last indefinitely. I’ve seen compressors in factories that have been lovingly maintained for thirty years and which, given continued loving maintenance, should last at least thirty more. I watched the mechanic in an Egyptian bottling plant manufacture spare parts for his compressor from a pile of off-cuts in the yard. No it wasn’t the prettiest piece of equipment I’d ever seen, with at least half of it having been replaced with local scrap over the years, but it still functioned to a high level of efficiency.

Compressed air is not without its dangers. But as an energy carrier it sure beats hydrogen in that respect. And compressor technology is old and proven. Over the decades we’ve made it pretty damn reliable. I have a hunch that “reliable” is exactly what we need right now.

Posted in: Opinion