Prius Plug-in proves Toyota’s commitment to continuous improvement.
Wayne Gerdes -
CleanMPG - April 12, 2010
San Diego, CA -- The largest gathering of Prius PHEV-12/13’s in the history of the U.S. occurred today at a conference dedicated to “Sustainability”. And the gathering proves once again that Toyota is not standing still.
25 brand new, just off the boat Prius PHEV’s destined for the U.S. Fleet trial (previously announced any number of times at CleanMPG) were available for Journalists to drive not only under Plug-in power but in charge sustaining mode as well. And like a child at Christmas, some were more excited to try out the latest wares more than others… I think you all know where I stand
Although I cannot go into the tech detail, I am allowed to discuss the driving impressions. While we wait for LEAF’s to fall, Focus to be attained and Volts to be charged, the OEM 2010/2011 Prius PHEV offers hundreds of thousands already familiar with the icon everything they have come to know and love plus a lot more.
The Drive
Along with the tech detail pronouncements we will have available after 08:30 AM tomorrow morning (you do not dare break an embargo or you will never be invited back
), noticeable improvements were seen from my own short 20 mile drive in a number of areas.
The Prius MFD now includes a few new screens and information on the screens we are all familiar with. On the standard HSI screen, there is now an all-electric countdown allowing one to consider when and where you will run out of juice and the ICE will take over in standard Hybrid mode. This range counter is also shown on the energy screen.
The HSI threshold bar disappears under PHEV “EV” mode and you have the entire range to the PWR section before the ICE will kick on and assist for either power or above 62 mph (see below).
In addition, the EV button is gone and if you have juice available (kWh) in the sub packs, a large EV icon appears in the standard display.
I had 8.5 miles left when I took off and at 8.3 miles, the Prius transitioned into charge sustaining mode or standard hybrid mode. In heavy afternoon traffic on an urban drive route with ~ 500’ descents followed by 500’ climbs again and again, the range counter would climb rapidly under heavy regen and drop precipitously when climbing. If you are on EV, you can regen the Sub-Packs and continue to use it until 0.0 miles AER (All-electric range) appears. I saw the drop out occur during a heavy climb at 1.1 miles left and once the climb was complete, the EV Icon reappeared and I was able to use the remaining charge until 0.0 miles. While the ICE was on for just 30-seconds or so to finish the climb, coolant was dead cold yet the engine shut down and after those 30-seconds and allowed me to finish off the last little bit of charge available in the last sub-pack.
I asked about EPA requirements given the emissions and the engineer said the Prius PHEV passed its cert’s under the FTP75 test cycle and all is good on that front. Finally logic prevails even at the EPA
Charge Sustaining Mode (just like the Prius’ we know and Love
)
If there is charge in the pack, it feels stronger than the std. NiMH pack. Easier to EV while climbing for example. In addition and a downside of the new PHEV, I was told are in Charge sustaining mode, you will only see a maximum of two bars to zero bars as a range of SoC and. Not good… But, just 5-minutes after I was told this while in the car, another 500’ drop occurred and up to 4 bars she went. The Engineer has a call into Japan about that one now that he has seen it
However, I could not find a way to coax the sub-packs to fill even a bit in order to go back to PHEV mode in order to allow regen to fill the “big” subs although I was told that is possible maybe. We’ll get that back as there are places in the country when regening down a mountain would be extremely handy
There is no On/Off button so as to force this situation with .1 miles of AER left or anything so it has to be done carefully if it can be done at all.
While this was an all-city drive with a maximum speed of 40 mph, the kicker is S1 through S4 has been tweaked. I never performed an idle check and out of possibly 50 Cycles (ICE-On to ICE-Off to ICE-On transitions, THERE WAS NO GLIDE FAILURES and that was with coolant anywhere from 125 to 191 degrees F!!! Not a single one no matter the speed, the Coolant temp or the terrain. You let off and she shut down!!! Halleluiah
Finally, the HSI turns back into the standard HSI we know from the 2010 Prius with the EV threshold sitting in the middle of Charge and Power and the car acts just as it does in today’s Prius. Other than the stronger EV, the two-bar indicator vs. Full range.
2010 Toyota Prius - ScanGauge X-Gauges
Unfortunately the CAN Bus traffic has been rewritten again so it will be some time before we will have SoC, Battery Current and Pack Voltage we have in the current Prius. There is still the goofy .02 GPH still being consumed when shut down but given the PHEV works like a PHEV is supposed to work, this is the best of the bunch today. 50 mpg capability on gas and 13-miles of true AER (All-Electric range) is apparently in the cards for just about anybody.
Tonight, Toyota is allowing me to take a Prius PHEV at full charge out on the highway for some of that testing but most here know what we are really after… That 62 mph glide after the sub-packs are depleted (other Journalists have seen as high as 64 mph on a highway loop) and if it can be exploited under charge sustaining mode for higher Highway FE than the ~ 70 MPG peak we can pull today? My fingers are crossed. Even if it cannot, I wish the PHEV logic was flashed to the regular Prius’ for all the reasons above.
Tomorrow’s Agenda
I will hopefully have more after tonight’s including colors choices, trim and equipment levels for the fleet but what I am supposed to be here for is a number of scientists discussing our global climate change, Economics of Climate Change, Urban planning and transportation after Peak Oil, Water Scarcity, Low Caron fuels, Rare earth metals and their use in batteries and finally Biofuels including Algae. Each topic has its own esteemed professor giving the presentation and I will do my best to keep up with all of that as well.
Wayne
I tried a number of times at varying slower speeds and only until she was below 45 mph would the ICE shut down 
Linear Mode
