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These carbon capture and conversion technologies are far more promising as a means of feeding atmospheric carbon dioxide into industrial 'aerochemicals' (to replace petrochemicals) and materials, than as a means of mitigating fossil fuel combustion CO2 emissions.

Obtaining a pure stream of CO2 concentrated from 400 ppm atmospheric sources is the optional approach for industrial chemistry processes (and requires significant upfront energy investment), but from here one can go almost anywhere, to methane or jet fuel or graphite electrodes or carbon fiber building materials or synthetic dyes.

However, it's unlikely these technologies will have much effect on reducing atmospheric CO2 levels. They simply eliminate the need for natural gas / petroleum / coal as raw materials for synthesis of necessary products.