When he squints, he can see, maybe 30 years down the road, Africa’s coast dotted with supertankers, docked at offshore rigs. But they wouldn’t be filling up with oil. Seafloor powerlines would carry renewable electricity to the rigs from wind and solar farms on shore. On board, one device would use the electricity to desalinate seawater and pass the fresh water to electrolyzers to produce hydrogen. Another device would filter nitrogen from the sky. Reverse fuel cells would knit the two together into ammonia for loading on the tankers—a bounty of energy from the sun, air, and sea. Ref
It’s probably not effective at a micro scale, but may be possible:
1, Make hydrogen using electricity from your PV system
2, Make Nitrogen from your PV System
Ref: http://homemadeliquidnitrogen.com/
3, Feed the Nitrogen & Hydrogen into a PV powered a reverse fuel cell.
http://www.sciencemag.org/news/2018/07/ammonia-renewable-fuel-made-sun-air-and-water-could-power-globe-without-carbon
4, Store the Ammonia for months or years. Or ship it around the world (in Ammonia powered ships) or through undersea pipelines
Then use the Ammonia as a fuel