Toyota: Plug-in Prius returning 65 mpg in testing
According to Toyota, its plug-in Prius hybrids are averaging 65 miles per gallon in real world testing. This is an improvement of 15 mpg over the recently-unveiled 2010 Prius. The secret to the big fuel mileage increase is a battery with the capacity to store much more energy than the unit in the standard Prius. This means a lithium ion technology and a much greater expense. So far, Toyota has not committed to a date when you'll be able to actually purchase a PHEV Prius for yourself, but it does plan to bring in another 150 test cars for testing.
Bill Reinert, Toyota's U.S. alternative-fuel vehicle manager, points out that this 65 mpg figure is from drivers who were instructed to pilot the test car the same as any other vehicle, so there are no hypermiling techniques required to achieve the mileage boost. Of course, the car must be plugged into an outlet to recharge its battery pack and fuel but mileage and range are still mostly determined by the driver's right foot. This is one reality that affects any car, including hybrids and fully electric machines.
[Source: Automotive News - sub. req'd]
Reader Comments (Page 1 of 1)
Dave 4:05PM (2/02/2009)
Their results are a bit short of what the Google RechartIT.org
project achieved with their PHEV Prius fleet. But what's also missing is what does the standard Prius get with their "normal" drivers - and what do other cars get with those drivers - like the Corolla and Camry?
Otherwise trying to compare their stated 65mpg from "normal" drivers to EPA ratings is comparing apples to oranges. They aren't comparable at all.
Quick summary of what Google's fleet got, lots more data on their site:
Overall Average:
Corolla: 31mpg
Escape Hybrid: 32mpg
Prius: 48mpg
PHEV Escape: 49mpg
PHEV Prius: 94mpg
City Trips:
Corolla: 27mpg
Escape Hybrid: 31mpg
Prius: 47mpg
PHEV Escape: 46mpg
PHEV Prius: 115mpg
Combined Trips:
Corolla: 31mpg
Escape Hybrid: 32mpg
Prius: 46mpg
PHEV Escape: 52mpg
PHEV Prius: 102mpg
Highway Trips:
Corolla: 39mpg
Escape Hybrid: 34mpg
Prius: 53mpg
PHEV Escape: 51mpg
PHEV Prius: 68mpg
I do wonder about the length of their highway trips - the PHEV Escape
numbers seem too high for trips that would deplete the battery.
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Chris M 4:59PM (2/02/2009)
The "Plug-In" Prius used by Google RechargIt was a retrofit using LiIon batteries, and the Toyota PHEV Prius tests were using a 2nd NiMH battery with less storage capacity, so it isn't suprising the results were less spectacular.
The Google PHEV retrofits cost about $10K, and I'd estimate the Toyota PHEV Prius probably would cost an extra $5k, based on cost of batteries and charger and other modifications made.
Dave 6:06PM (2/02/2009)
Good point, Chris M. Any idea how the capacity of the Toyota add-on pack compares to the one use by A123/Hymotion (which has a capacity of ~5kWh, right?).
jake 4:16PM (2/02/2009)
Is this with a mix of electricity from the plug or is it solely from the extra battery capacity (meaning 65mpg without plugging in)? It seems kind of low if you mix in the plug.
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Chris M 5:03PM (2/02/2009)
It is a mix. The size of the extra NiMH battery limits how much electric power from the outlet can contribute. A version using a larger capacity LiIon battery would produce better results.
Chris M 4:53PM (2/02/2009)
The Toyota PHEV prototypes are using a 2nd NiMH battery and a charger to get about 10 miles EV range. Toyota also increased the power of the electric motors and changed the gearing ratios to allow higher EV only speeds and better performance.
The stored electrical energy in the twin NiMH battery packs is less than the "Prius PHEV upgrades" that use LiIon batteries, so it isn't surprising the fuel consumption results were less dramatic.
I imagine the PHEV debate at Toyota is whether to go with the known reliability of the NiMH batteries with limited electrical energy and modest improvements, or go with the newer higher energy LiIon for more spectacular results but risking potential problems later on.
It isn't clear which battery type would be less expensive, as the price of LiIon has dropped, making them cost competitive to NiMH.
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paulwesterberg 7:02PM (2/02/2009)
You can get a replacement NiMH 1.3kwh Prius battery from toyota for 2.5k.
The battery weights 45kg.
The hymotion kit contains a lithium Ion battery pack that holds and additional 5kwh(6.3kwh total) and weighs 73kg.
NiMH: 0.0289 kwh/kg
LiIon: 0.0685 kwh/kg
So lithium contains double the energy density of NiMH.
The prius currently uses its battery pack to smooth out the ICE operation and recapture braking energy. Since all of the power comes from the ICE, there is not a lot of free energy floating around to capture so they can get away with using a small battery pack.
With PHEV the demands on the battery are much greater, toyota knows they will need to improve the technology, but they currently sell the most efficient mas production vehicle available for a reasonable cost. They need to balance price/performance and because they are the market leader they don't need to rush to release any new improvements. Like apple's ipod storage capacity they can increase it slowly over time, or offer premium models that can hold more juice.
With the synergy drive, electric/gas energy blending they can continue to size their battery pack significantly smaller than the volt, but deliver similar real world performance.
My prediction:
GM will be hard pressed to sell the volt for less than $40k and PHEV prius models will debut at the same time and have the same or better epa mpg for less than $30k.
GM files for chapter 11.
LM 9:14AM (2/03/2009)
Wow - There are actually credible, scientific statements being made in the AutoBlog forum for once. This is opposed to the bashing that typically occurs.
Good job guys/gals!
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Michael 10:38AM (2/03/2009)
Great, so when is Toyota going to sack up and produce a hydrogen car like Honda. You know, something that actually moves into the future as opposed to treading water where we are now.
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Mister D Barton 11:09AM (2/03/2009)
Electricity is actually the way to go. It's much safer than hydrogen and much easier to produce. The problem is where are people getting their electricity from? I live in a town where 85% of our power is Green Power (hydro) so if i had a Prius, i would be filling it up with a good amount of clean energy. A lot of people don't have that option, but if we can move to greener energies such as wind, water, solar, electricity for cars is the way to go seeing as how the sun won't die out for quite some time...and if it does, what we're driving won't really matter ;)
Chris M 6:44PM (2/03/2009)
Toyota will probably get a government grant to build a few prototypes like Honda, but neither company has any serious production plans. The cost of H2 fuel cells and H2 storage is far too high, there isn't a market for half-million dollar vehicles with very limited refueling options.
But even if they made a whole series of breakthroughs that brought the cost down competitive to EVs and PHEVs, the cost of H2 fuel would still be far more than electricity, and the availability far less. End result, electrics would still vastly outsell H2 buggies.
Michael 5:57PM (2/03/2009)
since hydrogen is the most abundant element in the universe, im going to go with its probably the best fuel. ill agree with electricity when someone finds a way make the vehicle charging procedure a matter of minutes. hydrogen can be dangerous of course, people who are mildly educated can recall the hindenburg; however, advanced versions of metal hydride and other future storage techniques will overcome these dangers. solar and other green power to run things that dont move and hydrogen to run the things that move is the way to go.
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Chris M 7:02PM (2/03/2009)
Hydrogen may be the most abundant element, but most of it is bound to other elements and it requires electrical energy or chemical energy to break those bonds to get pure H2 fuel. It would be better to use that energy directly, rather than use it to make an expensive, bulky, hard to store H2 fuel.
Take electricity. The combination of electrolysis, compression for storage, and PEM fuel cell is only 24% efficient. Compare that with 85% efficiency for charger and batteries, and it is clear - going the H2 route requires 3x more electricity. That is a major consideration for our limited supply of renewable source electricity, especially if you want to displace fossil fuel used for electrical generation.
Going with metal hydrides instead of high pressure carbon fiber tanks or cryogenic liquid H2 makes for safer storage, but it increases the weight and the cost. Current cost of any form of H2 storage is higher than a LiIon battery of equivalent range. Then you have the extraordinarily high cost of H2 fuel cells that require platinum catalysts.
The sole remaining advantage to H2, the "quick refill", disappears with the advent of "swappable batteries", or "10 minute quick charging", or "powered roadways" for unlimited range. All of those have already been demonstrated.
The future is electric.
MPG is useless. 7:02PM (3/06/2009)
As soon as you start using electric drive and power packs, you gotta report kWh (for the full at vehicle cycle) or you is lyin' on vehicle efficiency comparisons. Only total average kWh / 100 miles for full at vehicle cycle (everything full/charged to everything needign to be recharged/refilled (maximum range) allows for direct comparison between different vehicle types.
This has been the DOE/EPA efficiency standard for more than 8 years, if they would just report it, the sillies.
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Update. 7:02PM (3/06/2009)
@ Chris M 13
No, the present is electric, the past is gas.
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will cosby 3:26PM (4/20/2009)
Anyone have an average MPG in a Prius on the Taconic Parkway?
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JackC 6:08PM (5/28/2009)
A complete Li-Ion PHEV conversion kit is available right now under $2000 on ebay. You don't need to wait for Prius 2011 or Volt 201X
http://cgi.ebay.com/ws/eBayISAPI.dll?ViewItem&item=200344551230
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