I just made a trip from Hollywood FL to Ocala FL on the Florida Turnpike which was 284 miles. I managed to hit 70.5 MPG on the tripometer. I'm sure this isn't a record in this forum but I was pretty impressed in my 2016 Two Eco. At four gallons of gas, I paid more tolls on my SunPass.
What speed were you traveling at? Also was it moderate to heavy traffic? That is very good mileage on the interstate.
I have found that if I'm not in stop and go traffic, it's a moderately warm day, keep the cruise control on, and keep it under 68, I get great mileage. My mileage has gone down about 5 MPG with cooler temperature. Mind you, it's not "cold" here. It's usually in the low fifties.
I have done some smaller runs in florida ~10 miles with warmer weather but mine was no where near as good as OP's. This was taken in the Wee hours of the AM, no drafting, no lights or stops. Reset trip computer after about 7 miles warm up between two cities on my commute home. One note this is with climate control set at auto AC ~ 70 degrees and mine is not an ECO, but using ECO mode
Just picked up my 2016 Prius two and I feel my average mpg is not as great as others. Right now I got about 6,200 miles on it. Avg temp here in San Jose, CA is about 65 degrees. I get on freeway on avg 61.5mpg. I drive with Normal mode. Tried Eco mode and it was pretty much the same. i hear many of you guys getting sub to high 60s. I checked my tire psi and I made sure the psi is 1 above what is recommended on sideslip of the car.
I found it interesting that at the Prius mileage challenge yesterday they set tire pressure at 45. I set mine to the higher pressures used by the Eco. Front 39 Rear 36.
45psi seems a bit high IMO. I set my fronts at 39 and 38 rear. I have noticed a bit difference in MPG vs. the recommended psi.
It's how you drive the car as much as the tyre pressure that affects your mileage, but yours is a good ball park figure IMHO. The high sixties are probably from experienced Prius hypermilers, slow speed, gentle acceleration and braking. Yours will get better as the warmer weather comes back again.
I love going somewhere and complaining at how the traffic lights were all messed up and I only got 70 mpg instead of 101 in the PiP. They throw such a pity party for me!
LOL...my wife thinks I'm crazy for trying to reach mid to high 60s MPG. And yes, I do live in an area like the autobahn. The SF Bay Area drivers love to go on average 70-75mph. I try to drive 65 to 70 constant yet I still get honked at and get cut off.
If I set the Prius at cruise at 75 mph I get about 48 mpg in the winter and 53 mpg in the summer. I have 14,500 miles since July and I averaged 50.2 mpg of mostly highway driving.
These numbers make me smile! Having driven a Prius for four years, it still is difficult remembering that the car DOES use gas, and that that tank does have to be filled every now and then. Working out of a home office, I drive so few miles that it can take a month to empty the tank. Toyota, thanks for making this a problem! (And I bought my 2013V Three and 2017 Four because they are fun to drive...not because of the gas savings.)
I find with my Gen 2 that the wind direction makes a significant difference to the highway gas mileage. I always check flags along the way to see if I have a headwind or a tailwind.
You suspect correctly. The Prius is optimized for direct head-on wind. Or, highway speed into calm air. When I joined here 8 years ago, one of the threads had a graph of drag vs. wind direction. Front-quarter winds were worse than head-on.