mpg numbers are shown on website for 2016 Prius

I agree with everything you're saying. Depending on traffic I change my acceleration style. I don't know what it's like in Canada, but here in large metro areas everyone is in a rush and there is road rage and sometimes murder that does with it. Just yesterday my wive was moving more slowly then a "road rage" guy thought she should. He managed to get in front of her and slammed on his brakes, and she locked up her's, just narrowly avoiding an accident.

This is why I accelerate the way most drivers expect me to. It's not worth the 10 dollars a month I may save in gas to be stressed about road rage. I see it regularly, and not directed at me. Every time I get safely to work and back I am thankful. We have a lot of red light cameras and I brake on yellow. One day I'm probably going to be rear ended. Run light running is a sport here in Orlando.

 

The rating stayed the same; the guidelines on application changed but rating did not. It is not like they changed formula in 2006.

This is a good question, it depends to what extend Gen4 was optimized for JC08 (and as a result for NEDC). Aqua/Prius C was much better in JC08, but end up barely on par on EPA. The real life data (links to Fuelly) suggest EPA is much more realistic.

Toyota Prius Mileage | Fuelly
Toyota Prius C Mileage | Fuelly

before you go and say look Prius has about -1MPG less than Aqua, keep in mind that A) some of the Gen3 came with 17" wheels (not used for EPA rating), B) Prius is a bigger car and more likely to be used for long distance travel. EPA is not perfect but much closer to actual.

There could be some higher real life results, so Fuelly will actually show 52MPG average for 2016 when it is rated at 52, not 48 as it shows now for car rated at 50, but do not expect the miracles. It will not be 30%, 8% at most.

Get dashcam.

 

Yup, same collective insanity up here. I just try to keep a good space in front, keep my cool.We had a nutcase on our back bumper, maybe 6 months back. He continued weaving up the road, tailgating various cars. We got his plate, talked to the cops. The said they'll log the plate, and if they catch him on anything that previous incident would have bearing. One thing they told me: don't hesitate to grab your cell phone and call 911, a road rager trumps cell phone rules.

 

Don't be so catchy...you have misunderstood the word adjusted (as used by EPA) which is, as far as I understand: the raw city / highway cycles results adjusted for the sticker rating. Nothing to do with 'guidelines'...move-on.

 

when you say adjust, do you mean #1 or #2? as modify, alter, regulate, tune, fine-tune, calibrate, balance; or something else? because EPA haven't done any of that. They just explained how the tests procedures should be interpreted.

 

Only if they send magic ones to Europe and duds to the USA

Your model is a useful way to look at things.

It presumably applies only where the battery is not in play.

If I understand things correctly, the battery is in play much of the time to permit optimization of engine efficiency and/or to restore battery charge to the desired range?

Have you estimated the efficiency along the engine to generator to battery to motor path and what portion of overall energy delivery can be expected to follow that path?

 

One of the first things I had to learn. which took a couple of years:

• Below the hybrid threshold, ~42 mph - the battery holds the excess power generated by running the engine at a high BSFC point. Then the engine is turned off, saving engine overhead, and the traction battery maintains speed. The 'round trip' losses are << than the cost to keeping the engine running, ~2-3 wasted HP.
  
• Transition events - the transmission has two primary modes: (1) ordinary generator to motor, and (2) "energy recirculate mode" when the motor (MG2) is generating electricity to apply anti-torque to the ICE by MG1. In the past this was called "heretical mode" before a Toyota SAE paper explained what is going on.
• Burst power when exceeding ICE power - seen primarily when doing a maximum acceleration, hill climb, the traction battery can provide additional energy . . . BUT DON'T DO THIS!!! It is wiser to follow a semi-trailer truck up a hill as their power-to-weight ratio exactly matches the Prius engine power to weight.

One of the hardest things to master is the role of the Power Split Device which is a torque splitter to the engine. The magic is Toyota only applies as much counter torque as needed to get the 72% of power to take the more efficient, mechanical path. This 28% counter torque is not necessarily the same as the actual energy that takes that path. However, measurements suggest it is close enough.

Bob Wilson

 

I was quite clear - move on.

 

no you were not. If you were there wouldn't any questions.

 

Data &amp; Testing | Fuel Economy | US EPA

"Fuel economy information is required for all vehicles to determine appropriate values for fuel economy labels and for the CAFE program. The regulations clearly specify, for example, that both City and Highway test values are required for labeling and CAFE.The regulations also require that label test results must be adjusted using specified methods in order to reflect real-world fuel economy."

Bolding is mine.

 

You'll see the bar go into PWR zone on cruise, basically whenever it has to. Yeah, it's not like there's a threshold there. I find though, on level roads, I never need to go into that zone, and still have decent acceleration.

I hadn't watched RPM in quite some time, and it was interesting to see how disconnected it was. Standing idle is around 1280. It would just sit there, or drop one or two hundred, under a variety of modest load conditions. I get the impression the car is doing a fair amount of "Volt-like" propulsion, ie: even when the engine's running it's the hybrid motors providing grunt, and the engine sending electrons to the battery to help.

 

Very little improvement from Gen 3 to vanilla Gen 4 (4%) but a lot of improvement to Eco Gen 4 (11%). Interesting.

 

From EPA publication:

"Fuel economy information is required for all vehicles to determine appropriate values for fuel economy labels and for the CAFE program. The regulations clearly specify, for example, that both City and Highway test values are required for labeling and CAFE. The regulations also require that label test results must be adjusted using specified methods in order to reflect real-world fuel economy."

I wish EPA would report true (some will call them raw) non-adjusted city / highway results alongside with the adjusted numbers, at least in their fueleconmy.gov site which has a lot of other data.
These non-manipulated results are the certified ratings used to calculate compliance to CAFE standards.
I can understand the need of the adjustment for labeling (window sticker) and advertising so a potential buyer can know what to expect (very approximately though) in real life, but these are manipulated numbers that not influence the same degree all cars.
EPA claims the adjusted mpg figures are usually 20-25% below the true results of their 2 cycles test, these alone have variations and uncertainty, now take the Gen 3 Prius, the non-adjusted true result is 70.7 mpg (as far as I could find) so the 50 mpg adjusted is 29% below!
Part of the anomaly maybe here:

"While EPA strives to periodically update the regulatory test procedures such that all technologies are appropriately addressed, there may be instances when some emerging technologies or fuels are not able to be tested using existing regulations. Because of this, EPA has special regulatory provisions that allow EPA to direct manufacturers to test such vehicles using methods specified by EPA."

The 'find and compare' section of EPA site has vast information, why not adding this important info as well?
Let us judge!

Data &amp; Testing | Fuel Economy | US EPA

 

keep in mind that the text you are quoting so proudly is many decades old an haven't changed much if any at all for quite some time. Majority of it dates 70s when CAFE and EPA had split and by "adjust" they refer to EPA formula use. The actual test procedures are being added and phased out all the time. There hadn't been any significant changes in procedures for 2016 and neither adjustment formula nor existing procedures have not changed. EPA did issue clarifications on how the tests need to be executed and it may be of concern for those who cheated. The impact of these changes should be minimal.

As I recall initial reports were pinning Gen4 at 8% gain, and it was knocked down to 4% at the end. Coincidentally 4% is what the difference is btw EPA and real life fuelly results, so perhaps with Gen4 we will see it being dead on. But it is up to you if you want to believe into unicorns and 30% NEDC magic, noone stops you.

It is possible that there will be an additional bump to real life MPG of Gen4 due to better heat management. In cold weather it may take 10min for ICE to warm up, so those in cold conditions with short <20min commute will see the most gain. But this is special case and unlikely to have large impact on fuelly data. Unfortunately with first cars being delivered in Feb we cannot expect accurate data for at least until end of summer. More likely we have to wait year or two for cars on the road to break in.

 

what is interesting?

 

Here is Link to an interesting article about fuel economy..

"55 city, 50 highway, and 52 combined for five of the six trims" a little later in the article he said the city would be 54...


2016 Toyota Prius MPG ratings now official

 

Ha ha...EPA site gives data which is many decades old.
The page from this site that I was citing was last updated 9/11/2015 ! Why should we take you seriously?
I thing I speak for many here by saying you are contributing to these forums nothing but hate and false information to back it up.
Stop trolling around.

 

The CAFE values of a model might be found with a search. They just aren't of much interest to most, ordinary car shoppers. Many of them are probably unaware that fueleconomy.gov includes emission ratings for cars.