FuelEconomy.gov official ratings posted - 58 City/53 Hwy Prius Eco - 54 City / 50 Hwy for Prius

don't forget, the prius engine is off when coasting, but regen is active.

 

The answer is technical and involved. It might be easier if you have a Scangauge II and see the raw data yourself.

If you still want a technical answer, pose the question here: Efficient driving for a 1,000 mile tank | PriusChat

Bob Wilson

 

I wonder why the gen. 4 Prius didn't get a better EPA rating ?
Wayne Gerdes seems to get fantastic fuel economy even under wintery conditions.

2016 Toyota Prius Review | CleanMPG

 

To be fair, I think Wayne has topped out 120 MPG on a current gen Prius. I don't expect most drivers to get 73.5 MPG during the winter in a snowstorm... That said, Most reviewers have come in above EPA ratings without even trying.

 

Consumer Reports wonders why they didn't get worse.

In reality it takes a standard set of tests. Then you have a VW that codes a cheat.

Still there is enough raw data to make a credible model and metric close to what users report.

Bob Wilson

 

users are losers. the test is just to compare one vehicle to another. ymmv.

 

I hope the new Gen4 will have the same post trip avg mpg / avg speed / and trip time screen once you shift the veh off as the Gen3 Liftback... I really find that screen invaluable, especially for commuting and comparing trips..

I really don't like the fact my v doesn't have that ability with the v you have to push the reset on the touch screen every single time to restart the average.. Kinda a pain and I personally forget to do this except for road trips it seems.

The v also does not have the Gen3 liftbacks monthly mfd fuel savings / fuel cost screen in which one can input current fuel prices... Very nice feature that the Gen3 has...

 

agreed. i hope they took the best of all the screens and standardized it. i think danny said there was a lot of user programmable data.

 

That's wonderful if so!

Starting to like this Gen4 more and more

 

there's a lot to like, despite all the negativity around here.

 

The tail end does remind me of the starship enterprise but yes I am starting to see the light.

And what the heck I have owned my share of weird cars (Scion xb, Nissan Cube, subarus's, VW wagons, etc..)...

 

i don't mind the enterprise, but i would prefer the millennium falcon.nd the front on the white ones looks like a stormtrooper. tho car will be conflicted, and we'll be sitting in the crossfire.

 

No it ISN'T!

Monty Python: The Argument Sketch

A man walks into an office.
Man: (Michael Palin) Ah. I'd like to have an argument, please.
Receptionist: Certainly sir. Have you been here before?
Man: No, this is my first time.
Receptionist: I see. Well, do you want to have the full argument, or were you thinking of taking a course?
. . .
M: No it ISN'T! Argument is an intellectual process. Contradiction is just the automatic gainsaying of anything the other person says.
O: It is NOT!​

Bob Wilson

 

Why would they ?
Even they got 66 mpg with the two Eco !

 

Was that on their 'official' test track or from a preview drive?

 

Consumer Reports?

Their highway test is OK. They simply drive 65 mph and adjust for temperature. It is their 'urban' numbers that have always been FUBAR.

Bob Wilson

 

I am reading this thread for the first time today. Reading back several pages, the discussion was about G3 fuel efficiency.

An opinion:
After buying a 2015 Avalon hybrid (TAH), I am convinced that the same EPA fuel efficiency numbers could have been achieved in the G4 simply by installing a higher capacity battery. (size or Lithium). The TAH ICE runs less than my G3 did around town, because the charge has not depleted. It rarely starts at a stop light, or while parked listening to the radio while my wife shops. I rarely used "EV" on my 2010 Prius because it was "unavailable," but I use it routinely on the TAH. The less the ICE runs, the better the fuel efficiency. That is not to say that I don't appreciate all the technological innovations, and the new platform on the G4.

 

I guess I know how they get the MPGs now...

I got EV to work all the way to 70 mph!!!

 

When the Prius drive mode when the gas engine is turned off, it is still connected to the transmission - the gas engine pistons are driven not by the chemical explosion of gasoline but the transmission (which is in drive) so the momentum of the car is driving not just the wheels, but the internal power plant at the same time - it gets worst when the electric motors are activated to slow down the Prius producing electricity at a 10% to 50% efficiency ( 90% to 50% energy transfer loss occurs if you allow the regen brakes interfere with the coasting event. When the Prius goes faster than 46 mph - the gasoline engine is turned on just to keep the cam shaft at the same speed as the transmission when in Drive mode. .

The Prius software aggressively actives the regen brakes most of the time which is energy inefficient and the 2010 Prius poorly uses electric motor power - aggressively using electric motors at slow speeds (like in a traffic jam) without thinking it does not have much electric power left in the traction battery and causing the traction battery .to drain to very low levels forcing the gas engine to recharge traction battery recharge while in a traffic jams. A forced traction battery recharge causes the Prius MPG to drop like a rock. One can manage these shortcoming and mitigate the fuel efficiency drops if one has a scangauge II but it is not easy without a scangaugeII its almost impossible - the best solution for those without a scangauge II is to set a 2010 Prius to "power" throttle mode. Just by tweaking the Prius synergy drive software more mpg and do the same thing I am doing with a ScangaugeII manually - and I am not talking about a VW tweak to cheat on exhaust emissions - but threshhold activation controls for the electric motor based on the traction battery state of charge levels and threshhold controls for regeneration. .All this would be made easier if the Prius curb weight was just a tad less. A button to go gas engine only to avoid using the electric motor would to the same but most people probably would not want to manage it and would want the computer to manage it instead - this would lead to lower accelerations speeds but in a traffic jam where everyone is crawling around - it would be a good trade off.

The poor/bad driving conditions can cause a Prius's fuel efficiency to drop or increase more than most other vehicles - energy loss from cold driving temperature affect short trips even more than longer one because the Prius is designed to be low carbon emission vehicle first and it will sacrifice MPG for the first 10 minutes of the trip to make sure its emissions is as low as possible. For example, on a short .8 mile /3 minute drive to the grocery store it is not uncommon during the winter for my 2010 Prius to get 13 mpg. I manually install grill blocking in the winter time to increase my thermal efficiency on a my 2010 Prius but the new 2016 Prius has automatic thermal shutters to increase thermal efficiency in cold driving condition - having automatic grill blocking/thermal management is so much more effiicient when the driving temperature swings wildly as it has been this winter in the Washington DC area ..(. for example having it be 50 degrees in the day 25 degrees at night AND then the next day 35 degrees in the day and 10 degrees at night .- taking on and off the grill blocking manually has accelerated their wear and tear and now I have to replace it)

My 2010 Prius has had three flat tires over five years - due to road hazards/road construction trash damage. The temporary spare tire has come in handy.

In 2015 - I replaced my Yokohama Avid s33d with Michelin Energy Saver All Seasons. My fuel efficiency has dropped slightly with the Michelin Energy Savers All Season so far. - not sure if its my driving patterns or the tires.


Disclosure: I am a skilled hypermiler, I have a Linear Logic Scangauge II connected to my 2010 Prius which I have driven over 5 years, My mileage log for my 2010 Prius (Hyperdrive One, see hotlink below) is on Fuelly dot com and covers 5 years over +68000 miles with an overall fuel efficiency of 59 mpg, My overall mpg beats the 2016 Prius TWO, not II, Eco - but I have had to work at it to make it happen on a 2010 Prius III. - and some of the driving techniques I have used to get 59 mpg does involve rocket science- so there are a bunch of greek variable here and there in a long mathematical formula to explain it - so rather than make your head spin - I'll say for all intent and purposes I achieved 59 mpg by using magic!


Walter Lee

 

Full disclosure: I more-or-less never touch the shifter, leave it in Drive most all the time, never shift to Neutral. But I watched a video with Wayne Gerdes (CleanMPG) giving a guy hypermiling tips in a 3rd gen Prius. Multiple times he had him shift to Neutral.

The why's and wherefores I'm clueless, but he seemed think it was a good idea.