Earlier quoted context omitted.
> Can't make fertilizer or plastic out of solar energy. No, but if you're willing to spend a lot of energy you can pull CO2 out of the air and use it as a feedstock to make various fuels or plastics. Right now I think you'd have to burn 10 gallons of oil to make a single gallon so that's not efficient at all. But if you literally had more solar than you knew what to do with (like Germany does on occasion) you could u…
https://www.newlight.com/company claims to produce plastic from CO2 for less cost than from oil https://youtu.be/GlPyDLGKYSQ?t=1m15s
Rather than using natural gas as a plastics feedstock, they are using methane from organic sources (livestock bioproducts, landfills, other agricultural waste). They are using "greenhouse gases" but not CO2.