107 MPGe for Prius Plug-In

There's been some discussion of this on the Enginer forum. Enginer kit with the PHV would be a really good combo, the target voltage would be set to the plugin pack max (so as soon as you start depleting it the Enginer kit will just be running constantly) and the 4kwh pack should extend real EV miles out from 13 to about 30. For me, i have a 26 mile commute at an average speed of 32mph. I'd arrive at work with the car telling me i had about 5 miles of EV left. i could leave it in READY for about 30 minutes and be back up to 13 miles EV range, and get home all EV

 

Yep. You can also encourage it a little by pulsing using a certain gas pedal pressure. Normally it does this on and off automatically when the computer gets a chance.

This will be one of the mysteries to me right up to minute someone actually gets a real PHV and reports all the little feedback gimmicks, hopefully, Toyota gives us to monitor the HV.

Weather permitting, I think the best way to get great mileage would be to use the EV mode (if available) 1st during acceleration or during the first part of Stop-n-go so we run the HV battery down a bit. I believe this will leave more room to regen when and if the opportunity presents itself. I'm pretty sure this will be the "normal" hybrid mode of the computer operation, if so desired for people who just want to drive their car. I'm hoping "ECO" mode uses more or less of the power to keep the battery charged from the ICE instead of throttling the ICE RPMs up and down, because we all know any ICE runs much more efficiently at a steady RPM. I also think we'll get the best mileage much like the regular Prius with the battery not in the Green at the end of our trip.

 

I wonder if the Prius PHEV will have a "mountain mode" like the Volt to preserve charge in the battery pack for more performance going up mountains, or to save EV range to use as you near your destination as you re-enter the city?

 

Certainly didn't know that after driving it for past 18 months. My battery is always 2 bars empty from the top before and after my 33mile (55km) trip. My lifetime FE is 54MPG (4.3l/100km). I am guessing you guys perfected a way to use the battery more often... For me, I am happy to "just drive it" and blame the traffic for not letting me P&G

 

The first is not necessary, because Prius PHEV is naturally more ICE-moved when more power is needed. It is a blended hybrid

The latter EV-saver is probably offered, to face ZE zones.

 

How do they come up with 107 MPGe? I mean Opel Ampera (same as Volt) is rated at 147 MPG (1,6 l/100 km) in Europe. In a vehicle with more than one source of energy (gas + el. outlet) is completely useless to state one fixed consumption. I would be OK if they would tell us at least what distance it was driven on one charge.
A normal EU test cycle is performed on dyno driven only ca. 10 km Emission Test Cycles: ECE 15 + EUDC / NEDC

 

Ok have done some research on ECE test cycle and Plug-in Hybrid here is the document in German: http://www.bmvbs.de/cae/servlet/con...1-messung-co2-und-kraftstoffverbrauch-pdf.pdf

Test cycle is 100 km long, Ampera (Volt) used first 77 km 0 l/100 km and 23 km 7 l/100 km so combined 1.6 l/100 km (147 MPG).

Question is how did Prius get to 2.2 l/100 km (107 MPG)? Normal Prius uses 3.9 l/100 km to get that result it should get 44 km on pure electic and 56 km in hybrid mode. But if there are different modes (EV switches) for test is used Hybrid mode with most aggressive battery use. If Toyota is smart they made a hybrid mode in which battery use is so aggressive it uses it's charge in first 100 km.

This is called cycle beating. http://en.wikipedia.org/wiki/European_emission_standards#Cycle_beating

 

I'm sure those "different modes" aren't even brought up in measuring the PHV's mileage because most people, and cars, don't use different modes. And I'm sure Toyota has programmed the "normal" mode for aggressive battery use. Use as much electric as possible when accelerating and when speeds are below a certain speed that matches the power curve of the ICE. I have a tendency to think of the Prius PHV as a "fuel extended hybrid" which uses the battery to extend the gas as much as possible, particularly in "normal" mode or uses the gas engine (or driver) to extend the battery as much as possible, your choice.

 

Yes, but in practice, "mountain mode" and "EV-saver mode" are the same thing. It's just setting the point where the gas engine kicks in higher.

 

That is not strictly true, many Volt owners are asking GM to add a "hold mode" type setting that could float SOC at the current level rather than just setting a different pre-determined floor.

For instance lets say the normal charge discharge range is from around 80% to 30% and then the charge is sustained between 25-35%. Mountain mode changes the SOC floor to maintain it around 40% instead of around 30%. (purely made up numbers for illustrative purposes only).

Now if you happen to be at 40%, then it works exactly like a hold button would, however if you are above that point, say 60% the button does nothing until you deplete the battery down to 40% then it holds SOC there. If you happen to be cruising down the freeway at 70 mph during that time the depletion of the battery from 60% to 40% is not the most efficient use of your energy resources.

On the other hand, if you are already below 40% and put on mountain mode the ICE fires up and uses gasoline to charge the battery back up to 40% (as well as propulsion needs) so it is working harder and less efficient than it would if it were merely sustaining the charge.

What is anticipated with the PHV's button is that you will be able to activate it at any SOC and hold that state of charge while driving in Hybrid mode until you switch back (or even potentially raise it from regen).

 

In fact, switching Prius plug-in for saving EV SOC, would set the point as a regular HV Prius...which should be about 8kw demand to start ICE giving power to wheels.

 

The OP states it was 128MPG in the euro test, estimated 107 US.

 

Thanks for the explanation. This means that the test does no equivalence for electricity, so it is only a measure of the amount of gasoline used on the easier cycle for 100km or 62 miles. The volt gets better mileage since it stores more electricity. This test really doesn't tell us much about the epa mileage on us tests. Hopefully toyota will soon tell us the operating modes and epa estimates.

 

I thought the NEDC was used, but this ECE cycle is *much* better. Little doubt that each car used up its EV range on an easy cycle, since the Volt ran for 48 miles. This implies about 16 miles EV range with the Prius.

Since the cycle is 62 miles, 46 miles were petrol in the Prius, and 2.2 L were consumed = 21 miles a Liter, or 3L/100 km.

There is the magic ratio: PiP CS is 3/7ths the Volt's CS fuel consumption. This sounds *way* too good to be true. Anybody see an error ?

 

In English language, the test cycles/requirements...

(there was a previous link here in German)

http://eur-lex.europa.eu/LexUriServ/LexUriServ.do?uri=OJ:L:2007:158:0034:0105:EN:PDF

I haven't read yet.