if you solve carbon capture, you solve the problem. efficiency cannot be permanently solved. efficiency is still worth seeking, but if you solve carbon capture you don't have to bother with efficiency
for CO2 to be captured, you need some equivalent of the energy from sunlight in photosynthesis. so build these carbon capture facilities in places with powerful natural energy sources, and build them to last eternity
for CO2 to be captured, you need some equivalent of the energy from sunlight in photosynthesis. so build these carbon capture facilities in places with powerful natural energy sources, and build them to last eternity