[DesertVarnish]

For hydrocarbon synthesis, hydrogen production from electrolysis dominates the energy usage, along with driving the Sabatier process. DAC might be like 5-10%.

Higher CO2 concentration is better but certainly not needed, it doesn't make or break the economics.

[VBprogrammer]

I'm not going to argue over the numbers but any business which ignores such an obvious upside / upside scenario is not really serious about achieving economic criticality. It would allow a power plant, iron ore plant, cement producer, what have you, to make claims about their environmental credentials while simultaneously improving the efficiency of the process.