I’ve done a bit of googling around about e15 gas, and I’m not gonna lie, I really don’t know what to make of it, there seems to be a whole lot of contradictory info about it out there, some sources say it’s cleaner, others say it’s dirtier, and pretty much all of the articles I can find feel like they’ve been bought and paid for by one big megacorp or another.
When I kind of try to average together what I’ve read, and make no mistake I’m no scientist so I very well may be way off the mark on this, I think what I’ve come up with, is that it’s worse for smog and general air quality, but better in terms of greenhouse gas emissions.
It’s also ever so slightly more renewable, though really that’s kind of a negligible difference, 85% of it is still basically just regular gasoline, and the regular gas you usually buy is probably 10% ethanol anyway, so it really doesn’t make a major change in terms of how much petroleum you’re burning at the end of the day.
As far as saving money goes, you may get slightly worse MPG and/or performance using it, although annecdotally when I’ve used it, any difference was completely unnoticeable to me, YMMV (literally) depending on your car, the kind of driving you do, etc.
There’s also a deep rabbit hole to go down about corn subsidies and such that I’m not going to touch with a 10 foot pole right now.
If, and that’s a big “if,” my assessment is right, which I’m by no means confident about so please don’t take this as anything other than the musings of some asshole on the internet who’s skimmed a bunch of articles and is trying to piece together the facts, I kind of feel like this may be a bit of a wash. Probably something that needs to be really considered at the local or individual level to weigh the pros and cons, taking things into account like what your local air quality is like, how efficient your vehicle is, what you’d do with the money you save, etc.
Of course, everyone should do some research about this, make some informed decisions, seek out more info, be skeptical of claims on both sides, etc. Please do not take my word for it, my words, thoughts, and opinions about this issue aren’t really worth anything.