Rx 400h Ethanol Usage Reducing Gas Mileage?

[JoeRX400h]

Over the past few months I’ve noticed my gas mileage decrease from 29 MPG to 27 MPG. My RX has 5000 miles on it, and this reduction in fuel economy exists before and after the first oil change. After the first tank full with reduced gas mileage I noticed a sticker on the gas pump stating Contains up to 10% ethanol. I exclusively use 93 octane fuel as I consistently get better gas mileage over the 91 octane. I live in South Florida and it has been warm here for a while, so the air conditioner has been running all along. I know there are a lot of factors, just curious if anyone else has noticed this. I can't complain about 27 MPG as my driving pattern includes 20 miles on I95 at south florida I95 speeds 5 days a week.

[SOMEONE ELSE'S GOT MY NAME]

Over the past few months I’ve noticed my gas mileage decrease from 29 MPG to 27 MPG. My RX has 5000 miles on it, and this reduction in fuel economy exists before and after the first oil change. After the first tank full with reduced gas mileage I noticed a sticker on the gas pump stating Contains up to 10% ethanol. I exclusively use 93 octane fuel as I consistently get better gas mileage over the 91 octane. I live in South Florida and it has been warm here for a while, so the air conditioner has been running all along. I know there are a lot of factors, just curious if anyone else has noticed this. I can't complain about 27 MPG as my driving pattern includes 20 miles on I95 at south florida I95 speeds 5 days a week.

Welcome!

Ethonol with worse mpg's? Well yaaaah, it's pretty common knowledge that there is less energy per gallon in alcohol fuel, just as there is 20% MORE energy per gallon in diesel. What ever you do, don't run E85 in your 400h ~ or ANY car not specifically designed for it. Being more corrosive, special parts are required.

[Jim Clark]

I thought pretty much all gas was up to 10% ethanol these days. Your gas engine may be running more in the very hot weather. The A/C is electrically driven off the main battery packs. I believe the separate liquid cooling system for the front electric motor is also electrically driven. This may be draining the batteries faster and require the gas engine to run more for charging the batteries.

27 mpg average is very good.

[Statman]

I use 91 octane with 10% ethanol (by law in CO)...get 28 mpg.