I was today years old when I realised that the purification of silicon — needed for computer chips — is an incredibly carbon intensive process, and that in a post-carbon economy, we may not be able to do it at all.
So — no more computers, at least not with the technology we use now; and, probably, nowhere near as cheap or as ubiquitous.
In Our Time: Silicon
Episode webpage: bbc.co.uk/programmes/m002t2v2
Media file: open.live.bbc.co.uk/mediaselec…

Moz
in reply to Simon Brooke • • •yeah, nah. In a post-civilisation state where we're back to burning wood for heat, possibly.
But just at a basic level, he temperature control on the purification step must be so precise that it has to be electrical heating. Which means 'carbon intensive' isn't really the right word, they mean energy intensive.
Losing that wouldn't be "no computers" it would be close to "no electricity". Incandescent bulbs, resistive heaters, valves in your TV and radio. No internet, obviously
Simon Brooke
in reply to Moz • • •Simon Brooke
in reply to Simon Brooke • • •Moz
in reply to Simon Brooke • • •IIRC there's a whole forest of things, plus there's electrolytic refining as used for aluminium and a couple of other metals.
If you get into the history of metal refining it's kind of interesting, people have done a whole lot of things that are more than "dump in a charcoal furnace and see what happens".
For true insanity, turn it to plasma and fractionally distill that. I don't *think* that's actually done commercially.
Simon Brooke
in reply to Moz • • •if we are to continue to use things which are based on the semiconductor property of pure silicon, we're going to have to find other ways — which may not be economic in today's economy — to purify it.
If there are any.
This feels personal to me. For me, computers have been a liberatory technology — one that transformed a child who could not write into a highly skilled practitioner of a valuable craft. Without them, my life would have been much poorer — in every sense of that word.
Moz
in reply to Simon Brooke • • •this gets back to exactly *why* we are hellforming earth in the first place. If we achieve less than 1B people by 2100 (on current trajectory 'much less than' is likely) we could well struggle to make chips, and be using recycled solar panels for silicon.
I prefer the optimistic view that Trump et all will have their oil wars early and hard, pushing everyone else into sane courses of action. The ideal outcome would be fossil exports from Saud/Iran etc stopping permanently.
Simon Brooke
in reply to Moz • • •Look, the report the UK government is busy suppressing says we have four years left to make effective change. I think that's optimistic. But in any case it was written before Trump started his oil wars, and war (especially oil war) burns a huge amount of carbon to waste.
"Much less than 1 Bn people by 2100" is now extremely likely.
theguardian.com/commentisfree/…
The UK government didn’t want you to see this report on ecosystem collapse. I’m not surprised
George Monbiot (The Guardian)