Seems like US average is 0.855 pounds of CO2 emissions per kWh so this process looks like a significant win. Also grinding a ton of rocks doesn't use much energy if its just 14 kwh...
grinding: ~14 kWh/tonne olivine
absorption: 1.25 tonne of CO2 per tonne of olivine
emissions: 0.855 lbs CO2 / kWh
emissions: 5.4 kg CO2 per 1.25 tonne CO2 (1250 kg) absorbed
Why do there have to be CO2 emissions?
If this is to be an industrial mining scale operation that goes in with a 600 million tonne per annum target (similar scale to iron ore for steel mining operations) then the company building out the capital assets will setup EV's and solar on the grounds of both economy and PR.
You can see this with Rio Tinto Iron, Fortescue Metals, etc.