The missing link here is in total embodied emissions that go into production of corn. There's data available to help piece together a comparison [1, 2], and I'd love to work through this and get back to you with what I find. At a high-level, CO2 production from corn isn't net-neutral because the production of a corn, and then ethanol from that corn, is a fairly carbon-intensive process in terms of the energy it requires. Our process doesn't require most of the transportation corn does, and since the cooling tower is already operating, we don't have to incur any additional costs to capture the CO2. Our main costs are in the energy required for regeneration, and depending on the facility we're at, we may even get that for free in the form of waste heat/steam.
If you want to send me an email at josh [at] noyalabs.com, we can talk more about this there!
[1]: https://www.attisbiofuels.com/by-products/carbon-dioxide
[2]: https://watermark.silverchair.com/55-7-593.pdf?token=AQECAHi...
It'll also be interesting to balance the use of that land for trees vs. solar/wind as well. We'll need to put a lot of land to use to generate electricity, and some of corn's space might be occupied by that instead.
I thought that most ethanol is made from fermentation of corn, sugar, or whatever, and the carbon in that process came from the atmosphere originally. So, environmentally whether you make CO2 as a byproduct of ethanol production from CO2-absorbing crops or you extract CO2 straight from the air, it seems essentially the same because in both cases the carbon came from the atmosphere originally. What am I missing?