> Norway is now building pipes to pump CO2 down to the old oil wells.

You should know that injecting old oil wells with CO2 helps them produce more oil. The CO2 becomes carbonic acid under pressure, which then dissolves pores in the rock wider, allowing more oil and gas to escape.

Also, it looks pretty doubtful that CO2 will stay in gas wells for a long time. Eventually it'll find some fissure and due to the acidity any crack will be eroded wider till all the CO2 comes out like a fizzy drink.

But don't worry. Oil and gas companies will happily collect government subsidies for pumping CO2 underground to get more oil out to sell, in the knowledge that when the gas escapes in a few decades they can act all surprised...

Yeah, it’s been branded “enhanced oil recovery”, and iirc it’s currently the most economically rewarding use for CO2.

That's interesting, I'd always thought it was more the CO2 acting as a solvent to flush out the oil. Is there any reading material on this?

Note that €30 is obtained with pure CO2 as input. What's the cost of going from air to that? Or even from exhaust to that?

Most developed nations produce circa 10 tons of CO2 per person. Assume €100 to cover capital costs and inefficiency.

At ~€1000 per person we could easilly afford to go CO2 neutral. It's just a question of will