The high-value hydrocarbons combust to produce CO2 and energy. So at least as much energy is needed to turn that CO2 back into useful hydrocarbons. Where is tha

The high-value hydrocarbons combust to produce CO2 and energy. So at least as much energy is needed to turn that CO2 back into useful hydrocarbons. Where is that energy going to come from? I believe so far digging these hydrocarbons from the earth is still cheaper than using any energy source to turn CO2 back into useful hydrocarbons.