Modified PHEV Prius setting out on 1,100-mile, one-tank drive - but why?
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File this one under slightly sketchy (AFS Trinity style). A Florida Toyota dealer is taking a Prius on what he calls an "epic" 1,100-mile trip to Washington, D.C. and he wants to do it on only one tank of gas. Since the tank of the Prius is 11.9 gallons, that'd be quite a mileage feat. 92.4 mpg to be exact.
The dealer, Earl Stewart, knows a thing or two about getting the most mileage out of a Prius, and is organizing the drive to demonstrate "that hybrid electric cars are well suited to drivers who daily commute less than 40 miles, freeing them from the worry of ever-escalating gas prices." Well, fine, then, but this stunt isn't the right way to do it. First off, the Prius has been modified with a Hymotion Lithium battery and a plug. That's fine and cool. Second, during the trip, the driver "will drive the modified Prius 30-40 miles, and then stop and plug in for a few hours to recharge the battery before continuing the epic journey." This is exactly the kind of sketchy math that AFS Trinity uses for their 150 mpge number. Using this method, if Stewart wanted to, he could probabaly find a way to send the Prius to Cape Horn and back without breaking the fuel door seal. A better demonstration would be to have a customer drive the car for a month and then tell the media, "hey, this guy just drove to work and back for a month and never bought gas." That's amazing and realistic. Maybe even epic.
In any case, the car is called the Prius-Plus Electric Green Machine and leaves from North Palm Beach on June 1. For the record, the larger Ford Fusion hybrid can go 1,445 miles on a tank of gas if a few hypermiling tricks are used.
[Source: Earl Stewart via SunSentinal]
Reader Comments (Page 1 of 1)
kelly O'Brien 7:32PM (5/29/2009)
As a driver of an Hymotion-Converted Prius PHEV, this is just the kind of nonsense this will cause people to have heightened expectations, inevitable disappointment and ultimate rejection of PHEVs.
I refuse to put the "100+ MPG" sticker on the back of my Prius. That said, 75 mpg is realistic and not too ragged on my commute.
"Miles per gallon per tank" racked up in a PHEV owner's typical use is a much more realistic parameter to judge whether or not a PHEV makes sense.
Lack of charging infrastructure heightens the necessity to take a serious look at how one plans to use the car. Regular, long trips (100 miles or more) without the ability to charge at "point B" render the PHEV advantage moot.
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Nikki Bloomfield 8:28PM (5/29/2009)
As a driver of a converted PHEV prius (I did my own conversion) I too tire of over-hyped mileage claims.
But yes, I CAN do a whole month's worth of driving on one single tank of gas, plus daily recharges (sometimes even two). Average mileage for me in a month is about 820-850 miles - easily achievable without any special driving techniques in a NiMH based Prius with a 3.5 kWh traction pack.
Nikki.
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Nick P. 8:47PM (5/29/2009)
@Nikki,
Two questions:
Is it true that Toyota is planning to offer PHEV conversion as an option though its dealers? If true, would you go that route or is it still better to do it through a third party?
The Hymotion conversion kit is said to provide between 20 to 30 miles on pure electric for 10,000$USD. Is there a bigger battery available elsewhere? Something in the 50 to 70 miles? Not ready to buy a Tesla yet...
Regards,
- Nick -
Nikki Bloomfield 4:43AM (5/30/2009)
Nick,
Of course, if Toyota did an OEM Plug in Conversion AND it was only a few thousand more than the non plug in I'd consider it. Even with a range of 10-20 miles. My conversion cost £2,000 to complete and only gives me around 10 miles of pure plug in driving.
I'm hoping Toyota will be willing to let me drive their OEM plug in at some point. I'm curious to compare them. Obviously when you've designed the car you can do away with all the niggling little things I deal with, like the inability to do more than 32 mph in electric only mode unless I hack the car some more...
Nikki.
James 9:23AM (5/30/2009)
This type of misleading fuel economy calculation reminds me of the '100 MPG Hummer': http://www.design-impact.org/blog/2009/04/100-mpg-hummer/
We should account for all energy used while driving.
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NHG 2:21PM (5/30/2009)
I personally think the best way to calculate the mileage of a PHEV is Gallons per 100 miles.
100miles - 40 miles Electric = 60 miles at 48Mpg 1.25 Gallons. ---- 100 miles / 1.25 = 80mpg End of story...
For the Hummer
100 miles - 40 on electricity 60 miles @ 20mpg 3.0 Gallons. ------ 100 miles / 3.0 = 33.3 mpg..... Simple
C’mon guys tell me what you think?
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Kelly Erin O'Brien 11:03AM (6/01/2009)
NHG,
I appreciate your effort to "standarize" the numbers, but in my PHEV driving experience, your calculation won't provide a "real-world" picture.
That which intervenes are hills in both directions, and other such annoyances. What I see on my Hymotion-converted Prius is a radical drop in fuel economy once the aux battery is exhausted. So, in 100 miles, my mileage may drop to between 65 and 70.
It's all dependent of one's use of the car, which makes standardizing fuel economy a very sticky wicket.
montoym 1:31PM (6/01/2009)
You method of conversion is somewhat simplistic. While it does give a semi-accurate representation of how much fuel would be used during a 100mi trip, it fails to account for a number of other factors.
Basically, your method assumes long distance travel pretty much all the time.
For instance, if you can reasonably achieve 40 miles on all battery power, then an individual who drives less than 40 miles per day(the vast majority of us) will use possibly no fuel at all and would instead recharge the car at night by plugging it in.
Your method would imply that over the course of a work week(say 5 days at 40mi/day = 200 miles) those 200 miles would burn 3.33gal. of fuel (200-40 = 160/48mpg = 3.33). In actuality, the fuel used will be a small fraction of that and possibly none at all. However, the vehicle will still be drawing power from the electrical grid to recharge at night as well, so that energy should be included into the calculations as well.
It's definitely not as simple as your method makes it out to be.