I assume it would be using renewable, non-carbon producing forms of energy to power this; ie. geothermal, solar, wind, heck - even nuclear would be a good power source for this sort of machinery (with a consistent power requirement).
The more pertinent question IMO is, how many of these machines would be need to first bring global net-Carbon emissions to 0 - and the. How many more would we need to reverse the last century+ of CO2 pollution and bring air quality back to pre-industrial revolution levels?
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