To remove the co2 we put into the atmosphere will always take way more energy than we got out of putting it into the atmosphere in the first place. That is just thermodynamics.
To remove all the co2 we put into the atmosphere would take more energy than we extracted from fossil fuels since the industrial revolution. And all that energy would, of course, have to be produced in an absolutely carbon-free manner.
So this is and will remain an entirely impractical method of combatting global warming. MIT engineers know this. The people who funded this research know this. Why are they doing this?
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