Comment by dredmorbius

I'm not familiar with the projects you're referring to, any links?

What I particularly like about the US NRL research is (pardon if I'm repeating myself):

• It's based on two very well-established technologies: hydrogen electrolysis and the Fischer-Tropsch process. I suspect other power-to-gas processes are based on this or similar (Sabatier process,

• The novel techology is reasonably minor: CO2 extraction from seawater. Much of the research involves improving the efficacy of this process.

• It addresses the feedstock challenge: CO2 content of seawater is relatively large.

• It is a good match for sustainable energy sources, both base-load (geothermal) and intermittent / variable (solar, wind, tidal).

• It produces well-understood liquid hydrocarbons for which we have considerable experience in utilization.

• Costs and scale appear reasonable.

• It appears highly sustainable.

Dropping birthrates is indeed another positive, though that's got to move far further.