Algae may one day be commercially feasible, but that day ain’t anytime soon, and algae is land and water intensive.
A couple of years ago, before this was an issue for 0bama (and before all the search engine links went to positive sites & articles),
I was watching a show on producing biofuel from algae.
They showed a huge greenhouse full of tubes of algae.
They also showed the test tube a guy was holding between his thumb and forefinger containing the total amount of biofuel they had produced so far.