Re: Climate Remediation Engineering - Size of Problem

On 7/05/2025 7:10 pm, Liz Tuddenham wrote:

Bill Sloman <bill.sloman@ieee.org> wrote:
 [...]

an e-bike doesn't
generate any CO2.

 I am surprised that someone with your intelligence and knowledge should
repeat such a fallacy.
 Manufacture of vehicle

It doesn't have to generate any CO2.

Manufacture of batteries

That doesn't have to generate any CO2

Consumables (tyres, battery etc.)

That doesn't have to generate any CO2. Use natural rubber in the tyres, and you are extracting CO2 from the atmosphere.

Electricity generations (and the cost of making and maintaining the
plant)

Renewable energy generation is all about generating electricity without generating any CO2.

Road making and maintenance (tarmac refining, transport & installation;
road 'wetal'; concrete; street furniture; lighting )

It doesn't have to generate any CO2. Making concrete without emitting any CO2 isn't a problem that we have solved yet, but we haven't done much work on the problem so far.
Any solution it likely to involve capturing the CO2 emitted from carbonate rocks as they get processed, and burying it deep underground where silicate rock can soak it up by turning into carbonates. You can see that as kind of emission, but it keeps it out of the atmopshere
Making steel without emitting any CO2 is possible - you could electrolyse iron oxide in the same way that you electrolyse aluminium oxide - but the development of any kind of industrial scale process is still a long way off.

Disposal

That doesn't have to generate any CO2.
And the aim is not to eliminate CO2 generation - it's just to reduce emissions to a level that natural processes - mainly the weathering of silicate rock - can deal with.
The last big CO2 emission event (actually methane, but it got turned into CO2 within a few years of emission) - the Paleocene-Eocene Thermal Maximum from  55 million years ago - got cleaned up by natural weathering over about 200,000 years. As Joe Gwinn has pointed out, we could speed that up a bit, but that would cost serious effort.
--
Bill Sloman, Sydney