An acid that is produced through cellulose fermentation is acetic acid. It runs about 65 cents a pound. If this is the acid the article is talking about, then it is fairly cheap and abundant. The Chinese have been inflating the cost over the last several years due to its use of acetic acid in manufacturing.
That’s pretty expensive as I have to guess the energy density is lower than oil. Crude oil weighs about 302 lbs a barrel. At $100 a barrel that is about $0.33 a pound.
White vinegar is diluted (5%) acetic acid.
Acetic acid is vinegar.
We could easily manufacture the stuff by the boatload - near cheap as dirt.
Correct me if I’m wrong, but acetic acid is merely vinegar.