Comment by pbmonster

As long as you have well suited oil/gas wells to put compressed CO2 into, you'd much rather do that.

DAC of a ton of CO2 costs around ~2 MWh. Compressing it into a well costs ~0.5 MWh, but low temperature reduction to solid graphite costs ~10 MWh.

Solid storage in soil is much more interesting in bio char applications, because the char is full of nutrients and a good water absorber.