// That does not require too much energy // It inherently takes more energy to "unburn" co2 than you got from burning it in the first place. We burn co2-produ

// That does not require too much energy // It inherently takes more energy to "unburn" co2 than you got from burning it in the first place. We burn co2-producing fuels just because of this fact--they give us tons of energy! But it would take yet more tons of energy to unburn it. That is just thermodynamics. There is no magic science wand to wave here.