Doesn’t it also wear down engines more quickly?
It's not a total myth per se, because it once was and sometimes still can be true for engine components that are simply not designed to handle ethanol.
Such is not the case for pretty much every car built after the year 2000, roughly speaking. Every soft component in modern cars is designed to handle at least 10% ethanol, and effectively handle 100% ethanol.
Corrosion is not really an issue either. The E85 you get from a pump is anhydrous, and the only way you'll get things like phase separation is if water is added deliberately. Ethanol doesn't pull water into gasoline. That's a myth. It's not a dessicant. This topic has been studied and it's simply not worth worrying about.
Most cars on the road today, including those that aren't Flex Fuel, can run somewhere between E30 and E50 with no problems whatsoever. They can even run on E85 or E100 with either a software update or a piggyback device between the ECU and the fuel injectors, everything else remaining OEM.
A car running on ethanol won't rust, fall apart, or blow up. If anything, ethanol can be better for engines given that it burns cooler and leaves way less carbon deposits.
If a small engine today has seal failures or other issues, it's more likely to be the BTX (benzene, toluene, xylene) in gasoline and not the ethanol component.
By the way, I'm speaking from direct experience. Not only have I converted small engines to run on ethanol, but I converted my 2013 Hyundai to be a flex fuel vehicle.
[1] Because that's what's available around me, not because that's what they should be getting.
> Most cars on the road today, including those that aren't Flex Fuel, can run somewhere between E30 and E50 with no problems whatsoever.
That's straight up not true if we define "run" as "run as well as on E10" (granted I wish it was so I could save money on having to upgrade fueling for my cars).
With the huge focus on MPG manufacturers generally aren't overbuilding their fueling systems: My 4 series will "run" on E30 with a stock tune, but logging AFRs and fuel rail pressure will show it's a dangerous game where the ECU is pulling a ton of timing as the fuel system struggles to keep up.
Even with a tune, E20 is the maximum the fueling system can maintain without straight up running out of fueling and going into limp mode under heavy load
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The more balanced truth is: ethanol for vehicles is a complicated topic, because modern ICEs are complicated beasts.
Cars are designed to not break down on E10, but you will find some people argue (imo validly) that part of why car reliability dipped around the turn of the century was all the changes needed to support that kind of flexibility. Materials changed, engine management got more complicated (the fact that a car will run at all on E30 while clearly exceeding its fueling limits is a testament to that), etc.
Ethanol can be better for sure, my car is a million times more enjoyable on a simple E20 blend than California's awful 91 blend, but at the end of the day, ethanol fuel is a bit of a farce (and again, I'm someone who'd have a terrible day if we actually stopped producing it).
We're having the public pay to prop up our energy independence, and producing more emissions along the way. E85 prices don't reflect the difference in energy content, and the cost at the production side to make E10 blends. Gas would be cheaper for most people if we didn't have that requirement, hence why in times of economic need we've suspended the requirement.
Ironically the people who I personally see benefit most from E85 are people who are well off enough to use it for a performance boost, or businesses taking advantage of how much artificially cheaper E85 is. Average people get the short end of the stick and few to none of the benefits.
Variances between vehicles will always be a factor. This doesn't mean that most of them won't run sufficiently or even well with a higher ethanol ratio. Your experience with your 4 Series is interesting, and you seem to know a lot about ICEs, but all the research I conducted before I even considered trying E20 convinced me that the possibility of engine failure or damage is extremely remote.
I'll have to find them when I get home, but there were at least 2 studies I came across where researchers tested (I think) E20 on several vehicles from different years and manufacturers to see what would happen. The only issues the vehicles encountered were ones that had nothing to do with the fuel system.
In any case, it is a nuanced topic, though I struggle to say it's quite as complicated as your perspective.
> Even with a tune, E20 is the maximum the fueling system can maintain without straight up running out of fueling and going into limp mode under heavy load
That's very interesting. With my vehicle, it ran almost identically to E10 on E50 (yes I made sure that was roughly the ratio present in the tank), and on E60 it started to run rough and showed a lean condition code but was still perfectly driveable.
> Ethanol can be better for sure, my car is a million times more enjoyable on a simple E20 blend than California's awful 91 blend, but at the end of the day, ethanol fuel is a bit of a farce (and again, I'm someone who'd have a terrible day if we actually stopped producing it).
In any case, I find it an amazing fuel. Although my vehicle isn't optimized for the higher octane rating of ethanol, I experienced an obvious performance improvement on even E20 in terms of power. My bias was low in that case because at the time I was certain I wouldn't see greater power.
> Ironically the people who I personally see benefit most from E85 are people who are well off enough to use it for a performance boost, or businesses taking advantage of how much artificially cheaper E85 is. Average people get the short end of the stick and few to none of the benefits.
Do you think that's a limitation based on the availability of Flex Fuel vehicles, or the price of the fuel itself? Even when adjusting for the energy-per-volume using the most pessimistic calculation, E85 shouldn't be more expensive than gasoline. At current prices, E85 should be ~$0.50 less per gallon than regular gas when adjusted. At least that's how it is for the fuel prices near me.
But let's say that E85 and gasoline cost exactly the same per joule. All that would mean is that E85 has less range. If EVs have taught us anything, it's that many people don't mind having less range.
But modern engines will happily run like that for a long with no outward issue (especially if you're not someone that strains them), so some might argue that it's "running just as well".
I strain my engine, so it's not what I'd consider running well.
(Also all that is about E20-E30. "technically it's running well" won't continue all the way until E50 when at E30 you're already seeing the ECU needing to cope in the logs, and that's across many cars, not just my 4 series) -
And when I say ethanol as a fuel is a farce, I mean zooming out at the whole exercise, not on a personal level. It's amazing in my tank, easily providing as much of a performance boost as much more drastic options like messing with emissions equipment. Even adjusting for energy, it is still cheaper than 91...
But again, zooming out, for most people the performance difference is negligible because for them it'd be E10 vs E0, not E10 vs E30+. And they're paying a lot of money into the ethanol system for this marginal benefit:
- Ethanol is heavily subsidized by taxpayers at production, at its "natural cost" the energy difference would make it more expensive gasoline: https://afdc.energy.gov/fuels/laws/ETH?state=US
- Ethanol is subsidized again when its blended into E85 instead of E10, but most consumers are only even able to get E10. Even the physical pump dispensing E85 gets an additional rebate!
- Because some of the subsides are only for fuel over 10% ethanol, E10 which most people have no choice in taking actually ends up more expensive than both E0 and E85! In times of need we end up dropping the E10 requirement because of that: https://www.cnbc.com/2022/04/12/biden-waiving-ethanol-rule-i...
- The food that they do need, regardless of what they drive, competes with biofuel for farmland which is absolutely insane:
https://www.technologyreview.com/2011/03/23/196198/ethanol-b... https://www.reuters.com/markets/commodities/exclusive-britai...
- And then as this article shows, we're not even getting an environment
So at the end of the day, regular people using E10 are seriously getting nothing positive from it, but paying into it in multiple ways.
Overall I'm happy I can fill up my tank with E85, but the machinery around it is the literal definition of a frace.