Probably not a great idea to release a step by step for this on YouTube? Isn't nitric acid a direct precursor to... some very heavily regulated and dangerous things?
I'm sure lots of off grid solar powered independent farmers need a way to nitrogen fix their soil other than just buying fertilizer or growing beans or whatever.
Wonder if Azolla is economical. Its a floating plant, uses its nitrogen fixing bacteria, doubles in mass every few days and is top vegetable source by essential amino acids.