Putting the PHV through it's paces in the hot desert... (Rick's turn for the PHV)

On August 19, a Toyota Prius PHV will land in my driveway for a week (poor guy is driving it out from CA, then flying home), with someone more local coming to collect it sometime Aug 25th. My use case will be slightly unique as my commute is a bit longer than some of the previous testers who have reported in. I live 23 miles from work with my typical circuit being ~26 miles (including taking my oldest to school "on my way"), but my "current" routine is nearly 27 miles as I make an additional residential stop for my wife.

What that adds up to is ~6 miles of suburban driving (25-45mph speed limits), followed by 10.5 miles of suburban/rural driving (45-50mph speed limits), then 8 miles of freeway (65mph), finalized by 2.5 miles of rural/industrial (45-55mph) to the large warehouse where I work.

Sadly, there is no accessible power outside where I work that wouldn't violate Toyota and my employer's "no extension cord rule" (and even if there were, the chances of reserving such a parking spot would be slim to none). Even if there were power, the high A/C load after the heat of the day, combined w/ freeway driving would likely exhaust the EV packs before I got off the freeway during my return 25ish mile commute (pick up the family, then home).

My charging plans are to charge after 9pm or anytime on weekends, when the power is ~4.2¢/kWh (not considering taxes, etc.). On-peak power (9a-9p) is metered at ~7.5¢/kWh, but also contributes to a demand charge that's calculated based on the highest number of kWh used in any one peak hour period (last month was 8.2kWh at $13.372/kWh - mostly thanks to two A/C units set at 78˚F). Considering other charges, that works out to about 15.2¢/kWh. Needless to say, 10-14 miles on ~15¢ of electricity is more attractive than ~55¢ of the same juice for a mid-day boost. In mileage terms, that's 1-1.5¢/mile vs 4-5.5¢/mile for a 10 to 14 mile expected range. Considering 48 real-world mpg at $2.70/gallon yields 5.6¢/mile in my 2010 Prius, the electricity offset should "help" some, but it's impact will be most noticeable with off-peak charging.

I think the bigger impact would be if my wife could use such a car fetching the kids to/from school, cheer leading, etc. In our 2004 Prius, such driving yields mid 30mpg due to stop and go, high A/C load, and short trips. With the plugin on the newer 12p-7p peak system the power company offers (more expensive peak power, but a longer non-peak period that's only a fraction of a penny more expensive than current), she could plug-in after the morning trip, and have enough power to complete the afternoon trip (or most of it w/ the "idle" waiting w/ A/C) before peak rates kicked in. Some of the evening trips may be in hybrid mode, but that's ok as the peak electricity per mile would likely be just as expensive (though potentially less polluting considering most of our power is nuclear generated) as gasoline. After 7pm, she could plug in for the evening for the next morning, and we'd have a solid nearly all-electric routine with a car that had the flexibility to go further.

The only thing working against that type of plan is the desire for a hybrid mini-van in the family - the Prius (plug-in or otherwise) is cramped for a family of 5 on extended trips. We couldn't sustain 3 cars (a commuter for me, a 'round town runner for her, and a whole family comfort vehicle) for a variety of reasons, so adapting plug-in technology to larger hybrids would be a win-win for us.

I'll have more once I get the car in-hand, but I'd be curious if anyone has any questions or scenarios for me to try in my situation. I do plan to run the Kill-a-watt to determine the power-draw for "remote A/C" which can be used while plugged in.

 

Another couple of "observations" I'll be making will be the interior temperature difference (mostly seat of the pants) between my 2010 Blizzard Pearl solar and the PHV, both in "sitting out all day" situations and remote A/C differences at home. The PHV can run remote A/C from house power far longer than the solar package can off of it's hybrid batteries. I'm curious to note the real difference the PHV's extended A/C can make in an AZ summer - the 3 minutes of A/C in my car makes only a small dent.

 

Yes - we can talk about anything we observe with the current PHV demonstration. I plan to track full week MPG on one trip meter, and per-trip on the other. EV vs HV will be noted at the end of my morning, and at the end of the full day w/o recharge.

I did test full acceleration in Torrance in an onramp and freeway merging scenario and it felt "slower" than my 2010, mostly due to the extra weight in the trunk. Doing such a test in Phoenix wouldn't bode well anyway due to the rather high density altitude during the heat of the day. Additionally, I'd have to go a bit west where the speed limit is 75mph to be anywhere near legal when performing such a test. Even that said, part of my driving agreement is not to race the vehicle, but to drive it in a normal, lawful manner. Legal passing could fall into that category.

Would be interesting to note if passing power is greater w/ EV charge vs. in pure hybrid mode.

 

That could be possible, though being consistent on the gas would be difficult. The trick is to keep the HSI at the peak of it's eco band w/o tapping into the red "Pwr" band (which kicks on the ICE).

For those who have paid attention, the bar does seem to increase toward that limit w/o any movement in the accelerator pedal (at least in Eco mode).

 

I seriously think it'd be closer to 20 seconds. The "oomph" in pure EV is surprising.

 

I doubt it - the ICE would have to be spinning at that point.

 

The PHV is now in my possession. It's the same car that Tony and Evan had. I reset one of the trip meters, but didn't have time to charge before hand (I had to run Frank w/ the ad agency back to the airport ASAP). Despite, using the same route I use to go to work, then continuing down I-10 to PHX airport, then using Buckeye Rd. back to where I work, I managed 65.8mpg over 41.1 miles. My car might have done 55mpg w/ the same non-hypermiler driving style.

This would suggest that even w/o the advantage of plugging in, the Lithium-Ion batteries + inverter changes add more than just extra weight to the car ;-)

 

Yes, A/C was set to 76˚F in Eco mode (Frank had it set to Max, normal, and mid-level fan). Once I dropped Frank off @ the airport, I bumped it to 77˚F. Outside ambient was 100˚F.

 

My trip home didn't fare as well on MPG, because I went out for lunch (2 mile trip w/ lots of AC). Overall MPG is in the 58 range, and trip home was about 53.2mpg (started off in the 30s).

I mentioned lunch - at about 2pm, the car read 115°F sitting in the sun, and settled at 108°F. With my borrowed heat-shield, the car was still significantly hotter inside than my solar equipped standard Prius - enough where I said "woah boy, it's hot".

The charging cable is about 25 ft. I measured this morning and noted that I'd need at least 23ft to reach and still keep the car in my driveway, otherwise my wife would lose her coveted (and cooler) garage spot. The cord reaches with plenty of slack.

After taking a few pics, I put the Kill-a-watt meter on just long enough to get some figures while charging.

The "adapter" saps about 0.03 Amps not doing anything.

Plugging in, the car will ramp up it's usage, 50 watts, then 2-300 watts, then 700, then about 1290, with spikes up to 1300 watts. The cable is rated at 12A, and it's actual usage was 11.87A average. I let it go a few minutes while I took some readings.

I then activated remote A/C. A few things I noted, despite being 102°F after sun-down, the A/C compressor doesn't spin very fast. The air does blow cold, but the blower doesn't race. All that, and the unit is drawing between 1000-1200 watts (fluctuates) while cooling. After 10 minutes it'd be effective - but being before 9pm, I wasn't willing to go very long. Note - the display did note that charging was interrupted - expected and documented side effect of using remote A/C before it was done.

The car will NOT let you start while plugged in - a nice warning message pops up on the MID, reminding you to unplug before you depart.

The 5-10 minutes of charging netted 0.4 miles of EV range on the display. Letting the A/C run for 30 seconds (to compare "compressor noise") knocked 1/10th of a mile off of the range. I can tell already that if I'm not conservative w/ the A/C, 14 miles will be a pie-in-the-sky number.

Now it's 9pm - time to charge at 5¢/kWh instead of 15¢/kWh