Adding an EV (electric only) mode to the 2010 Prius has been quite a tease for 3rd Generation owners over the last year. You get in your Prius, press the EV button, and the computer goes "beep beep", telling you that the car isn't ready to jump into EV mode because the engine isn't warmed up yet. Once the engine warms up, you press the button again - "beep beep!" This time either your Prius' battery State of Charge (SOC) isn't high enough, you're accelerating too hard, or you are driving faster than 24 miles per hour. I now see why Toyota programmed the EV button this way: They want you to fall in love with the Prius PHV Plug-in. Guess what? Their sinister plan worked.
This week Toyota has been hosting a Sustainable Mobility Seminar here in sunny San Diego, and one of the perks for coming to the Seminar has been test driving the Prius PHV. In fact, several of the featured speakers at the seminar are from Boulder, Colorado where 18 of the Prius PHV demonstration vehicles will live in the SmartGridCity project. Overall there will be 150 Prius PHV vehicles in the U.S. during a two-year test phase. Each car is outfitted with systems from Qualcomm that record and send back information on how the Prius PHV is being used. Information including how often a Prius PHV driver charges the car, how long each car is plugged in, driver behavior such as the % of time the car is in EV mode vs traditional Prius HV mode, overall MPG, and range are all being reported back to Toyota and in turn Toyota will share that information on their http://www.toyota.com/esq site for everyone to see. All of this information will help Toyota tweak and refine the Prius PHV before it hits the consumer market in 2012.
So, what's it like to drive one of these Prius PHVs? Thankfully, it's pretty much exactly like driving a 2010 Prius but without having the engine kick on. Depending on driving conditions (including the driver themselves), the engine will never kick on over its 13 mile EV range. After its 13 mile range is depleted, you're out of the heavenly land that is EV driving and back into driving the trusty and efficient 3rd Generation Prius.
The official numbers from Toyota say that the highest speed you can achieve in pure EV mode is 62 MPH. During my drive on the interstate, I was able to "stealth" at up to 70 MPH. It's an odd but awesome feeling to accelerate onto the I-5 freeway without the gas engine ever kicking in. As you'll see in the photos, Toyota has replaced the "ECO" indicator on the Hybrid System Indicator screen with the little Prius leaf icon we're all familiar with. When it is lit up, it says "EV" and indicates that you are driving without any assistance from the engine.
Prius PHV Plug-In Test Drive Gallery
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When the engine does kick in, it feels like Toyota has refined the Prius' software even further to make the transition from EV to HV more seamless. At one point while driving up a lengthy, steep hill, the Prius' engine kicked in to help me crest the hill without me even noticing. Had I not been paying special attention to the "EV" indicator on the HSI (Hybrid System Indicator), I would have never known.
The Prius PHV demonstration program vehicles have several changes that you're probably already aware of from previous stories on PriusChat, but I'll run through them again for those of you who haven't been keeping up. The PHV has a special Blue Mica Metallic paint that is unique to the Prius PHV. You won't find it on any other Toyota, Lexus, or Scion anywhere in the world. It has special badging and decals to indicate the fact that it's a Plug-In. It even has special floormats with "Prius Plug-In" embroidered on them. Any member of the public is going to see one of these demonstration vehicles on the road and know exactly what they're looking at. Any current Prius owner will also notice that the rear cargo area is raised up about two inches, though I don't think it's very obvious to non-Prius drivers. The storage under the cargo area is gone to make room for the extra 220+ pounds of lithium-ion batteries and the new fans and ductwork required to keep the batteries cool. The battery pack is separated into 3 separate modules: 1 for HV mode (replacing the current NiMH battery in today's Prius), and 2 separate modules for EV driving each having about 6.5 miles of range. Why was the system designed this way? Not sure, but I certainly don't think it's the way the production PHV will be laid out. Toyota has placed a tire "fix-it" system in the cargo area since you won't have a spare tire, and all of the Prius PHVs will have access to a 24-hour roadside assistance program (SOS).
Back to the driving. After the city route I pulled back into the hotel with the Prius' screen showing 99.9 MPG. What was my true MPG? Who knows. That's one of my complaints in the PHV that you'll read about in an upcoming article. The new screen on the Prius showing your percentage of driving in EV vs HV mode tells the real story. With the city route I averaged 84% of the time in EV mode and 16% in HV, or traditional Prius mode. I'm proud to say those numbers were the week's best. In the mixed city/interstate route I pushed the car a little harder and ended up doing a little bit of my own route which inadvertently included lots of hard La Jolla hills (to my MPG's detriment). Even while doing some hard accelerating, testing Power mode, and seeing how hard I could push it until it came out of EV mode, I ended up averaging about 79 MPG over a 20 mile stretch.
That brings me to my conclusion on the Prius PHV: It's not a car for everyone, just most of us. I'll steal a line from Ed Begley, Jr. when he said, "The electric car is not for everybody. It can only meet the needs of 90% of the population." If an EV can meet the needs of 90% of the population, that means that the Prius PHV can meet the needs of 99% of the population. Instead of needing one car for shorter, less than 100-mile trips and another for extended trips, the Prius PHV will cover both needs. Price and availability are still unknown, but Toyota has 2 years to work out the kinks and perfect their battery technology before coming to the public market. And when they do, I'll be the first in line with my hand up, saying "I want one."
