I had left instructions for the dealer to just put in enough gas to drive about a half dozen miles to a station that sells real gas. But they filled it up with E10 that I don't want that sitting in the tank for months. So I started driving in hybrid mode and set to power to get the gas consumption up. Just on a quick lunch trip (4 miles each way) the trip summary indicated MPG in the 70s! It looks like it will be a long time to get rid of that E10 junk.
I wouldn't worry about it. I've seen MPG in the 30's while driving up a mountain (and on the way back down it uses no gas and recovers energy, so the overall average is greater than 60). And the other day I saw around 9mpg after I warmed up the engine to defrost the windshield and pulled out of my neighborhood (maybe 1/3 of a mile). You could use Charge mode and then use the excess electricity to power your house off an inverter (not very practical). Or you could put a large tank of water in the car, up to the payload capacity, and drive it to the top of a mountain for storage. Repeat a few times until you're out of gas. When you want to generate electricity later you could go get the water and regenerate electricity with the extra mass on the way down. Basically pumped hydro storage. Or just go for a really long drive. I could go from Denver most of the way to Salt Lake City on one tank of gas. These cars are meant to be driven.
Or simply not worry. Assuming the Prime is like my 2016 Camry, it is designed for E15. So E10 will not harm anything.
pump it out and put that E10 in two cans. put in $10 of real gas, from the direction your taking in your initial post, $10 worth could last several months.
So how long did the tank last? I would be heavy with EV and I do not want E10 sitting in the tank for months.
The car has seen E10 for at least 38,000 miles. Ethanol doesn't become more corrosive with age. Car fuel tanks are not like the plastic tanks used to fuel lawn mowers. They are well sealed to reduce evaporative emissions. That sealing keeps excess moisture and air out. If it did not, E0 gas would age in the tank, forming gums, varnishes, and dropping in octane. Becoming a potential damage risk to the engine and fuel system. Ethanol is actually a good cleaner of such deposits. It can actually loosen up the crud in older vehicles and equipment, leading to blockages. Any water in the fuel was picked up before it got to your car, and it is in E0 gas too, where it can be more problematic. Besides, water in ethanol has been shown to prevent it from corroding aluminum.
Good to know you're all out of things to worry about. E10 is pretty standard in many, many places. No long-term harm that I've ever seen. In fact, for winter it should be beneficial, right? People pay money for ISO-heet or whatever winter fuel additives, that are just alcohol. Have a drink of real alcohol to cheers with your car - then don't let it bother you. It really is not a big (or even small) deal.
Humm, if I have to pay over 20% mark up for the ethanol free pure gas available in our are, even at our high electricity rate, EV drive may become cheaper mode on my PRIME. Currently, I am paying more on electric drive than gas drive with E10 regular gas costing $2.45. But Nop, I am still going with cheap blended gas.
There are many gasoline additives available to handle the real and imagined problems of ethanol in gasoline.
