michael_nielsen

If the cost of scalable sequestration can be brought down to order $10^1 per tonne, then (US-wide) negative emissions starts to look comparable in cost to the Clean Air Act (according to the EPA's numbers).

Of course, we're 1 to 2 orders of magnitude away from that price point today. But commitments like this will start to drive the price down, underwriting improvement in sequestration technology.

Have you seen any evidence that it would be possible to get near $10/tCO2 for DAC? I’m assuming it’ll end up around $100/tCO2, which is still plenty cheap for producing carbon-negative fuel ($1/gal extra) for aviation etc.

I've no idea - as I think we've discussed previously, the tech is all over the place at the moment (see, e.g., the National Academies Report). My general impression is just that no-one's tried very hard, at scale - it's not a though billions of dollars have been put into this.

All very true. Given the thermodynamics and kinetics, I’m skeptical that even $1B would bring DAC costs below $50/tCO2, but even at $100/tCO2 we‘ll have all the tools we need to cost-effectively solve climate change.

What argument are you referring to?