MPG on cross-country road trip

I'm on long trip across country and thought I would post my results. I've been driving relatively modestly, but not hypermiling by any means - basically just riding EV whenever I can, using ECO mode on highway, pump and glide down hills 50% of the time. I don't have the tire specs on me, but I am running lower profile tires (std for the premium wheels of the Prius five) at Toyota's suggested psi .

• NYC --> DC: 52 mpg (avg for entire trip). I really took it easy and used ECO mode the entire time. No AC. I'm really surprised I didn't get more, I've heard that 55 mpg is easy if you pump + glide, have an easy foot, and average 55 mpg.
• DC --> Charleston, WV --> Lousville, KY --> Nashville, TN --> Memphis, TN --> St. Louis, MO --> Kansas City, MO: 47 mpg (avg for entire trip). Not as conservative w/ gas pedal (highway speeds of ~ 65mph) and used AC 60% of the time.
• Kansas City, MO --> Dodge City, KS --> Boulder, CO : 45mpg (avg for entire trip). AC here and there but definitely gunning it more often across KS and up mountains in CO. I did have one night sleeping w/ the AC to keep moisture down during a severe storm, but outside temp was relatively the same as what the inside was set to.

I know for a fact a few things contributed to the reduction in mpg: the rolling hills of Kentucky and WV, STRONG headwinds along most of the Kansas prairie, and having to gun it up mountains in Boulder, CO. Are these results decent for a 2013 w/ ~75k miles?

 

true dat

 

That’s pretty comparable. 47 sounds about right given those speeds. I’ve been fortunate that I can take things slower at around 60-65 on the highway. I’ve also noticed that it really helps going slower up hills and then coasting down the other side of the hill, it doesn’t seem to disrupt traffic to do it this way as long as you were in the slow lane when you’re climbing.

 

I’m just using regular 85 octane fuel. It seems a little counterintuitive, but I’ve noticed the car is at its best at around 60 to 65, any slower and the engine seems to work just as hard if not harder to maintain the same speed. I do understand irresistible and how anything over 50 to 55 mph generally reduces efficiency, but for some reason the momentum of this car seems to play a major role add around 60 to 65

 

I am now at 4300 miles and averaging 46.2 mpg for the entire trip. Up and down Colorado Rockies, through Utah national parks, and mostly highway speeds.

It seems that the mpg gains while coasting outweigh the losses from climbing mountains oddly.

 

• NYC --> DC: 52 mpg (avg for entire trip). I really took it easy and used ECO mode the entire time. No AC. I'm really surprised I didn't get more, I've heard that 55 mpg is easy if you pump + glide, have an easy foot, and average 55 mpg.
• DC --> Charleston, WV --> Lousville, KY --> Nashville, TN --> Memphis, TN --> St. Louis, MO --> Kansas City, MO: 47 mpg (avg for entire trip). Not as conservative w/ gas pedal (highway speeds of ~ 65mph) and used AC 60% of the time.
• Kansas City, MO --> Dodge City, KS --> Boulder, CO : 45mpg (avg for entire trip). AC here and there but definitely gunning it more often across KS and up mountains in CO. I did have one night sleeping w/ the AC to keep moisture down during a severe storm, but outside temp was relatively the same as what the inside was set to.
• Boulder, CO --> Grand Junction, CO --> Arhces NP --> Zion NP --> Bryce NP ---> Salt Lake City, UT : 46.2mpg (avg for entire trip). LOTS of mountain climbs in Colorado & Utah. Sleeping every night w/ the AC to keep moisture down. Outside temp was relatively the same as what the inside was set to. ECO mode as much as possible, gliding down hills, but still maintaining ~65mph on highways. Mostly highway miles overall on this trip.

Seems like I can't update OP, so I'll just keep an updated log with new posts. Already at ~4,100 miles for this tripe - sounds like 46.2 mpg ain't too bad for this type of driving.

 

The mpg I am quoting is for the total trip, not individual segments. I am showing various segments of the trip to note specific environment/trip factor that could contribute to a rising or lowering total mpg.

Really interesting things you are pointing out - I’ll have to read up more on the Atkinson-cycle as it relates to altitude

Yeah, the folks that argue against downhill never makes up for uphill would be ignoring the range that EV can enhance a coast on gradually flattening downhill and flat land after the descent. It’s basic physics, they would also be correct in other circumstances.

 

I'll also add - I've been running the heat at night (all night) for the past few days since I am now up North where it is snowing and the average mpg goes down 0.2 each night (currently at 46.1mpg for 4800 miles). The gas guage doesn't move

This car is growing on me. Incredible machine.

 

Well said . The Prius definitely has to be put to use and experienced to be truly appreciated.