Plug-in Toyota Prius Hybrid Test Drive: Is 100 MPG Possible with A123 Systems Hymotion Kit? - Popular Mechanics They only got about 70 mpg. Here is my response. It was easy to get 100+ mpg. www.peakoilgarage.com Over 100+ mpg for 22 miles
Real-World Long-Term data is what matters. Brief measure samples don't represent an on-going expectation. (They can be very exciting though.) Google's RechargeIT mini-fleet is a good example. Their average is 69.2 MPG. .
We are participating in the V2Green fleet tests. From verbal comments of the fleet manager, I can tell you that quite often the users of fleet vehicles are some of the worst people to have testing these systems. Often the users are not even plugging in the vehicles at night so they start the next day with a dead battery driving around with 180 lbs of dead weight. They really don't care. It is not their priority. They just drive the car around during the day doing their jobs. It is really hit or miss with every vehicle depending on the employee it is assigned to. It would be much more valid to gather the data of owners who actually own their Prius and who paid for the Hymotion system from their own pocket. Those are the people that are putting this through real testing. They are actually plugging in every night and during the day whenever possible. Also, it takes a few days of experience to learn the Hymotion system and how best to take advantage of all that extra electric propulsion. If a car that is being monitored is getting a bunch of different drivers (with little Hymotion experience) and they just drive like they normally drive, then their results are going to stink. The Hymotion system can EASILY achieve 100+ mpg. But it is also easy to get much lower if you just stomp the gas all of the time and forget to plug-in.
Another thing people need to realize is that there are two different types of calculations to consider. Pure EV mode of less than 34 mph. When doing that for the entire battery, 22 to 25 miles is possible, depending on how much is stop and go with lights and traffic. Steady with no stopping will get you at the higher end of the range. At highway speeds of 55 mph to 60 mph with cruise control and flat terrain, you will get about 40 to 50 miles of range and 140 mpg to 180 mpg. The ICE is at idle RPMs and you are drawing approximately 0.30 gallons per hour. When Hymotion/A123 claims 30-40 miles of 100+ mpg performance, that is EASY to achieve with about 1 or 2 weeks of experience. There are at least 10+ other Hymotion owners on this website who can likely confirm my estimates.
I think one of the challenges is that PHEVs, and Prius conversions in particular are probably much more sensitive to driving style and trip length/speed/route than regular Priuses. Some of the folks on this board have illustrated that 100-180mpg is very achievable over a long period of time with some effort. The Google data is also all over the place depending on who is driving, how they drive, how far they drive, and whether they remember to plug the car back in and/or turn the pack on. A number of their datasets are offline at the moment, but one of their cars is averaging 61mpg, while another is averaging 98.2mpg even under these far from ideal circumstances. Google.org Google.org Rob
I posted a couple of things as well in response to some of the comments, we'll see if they get posted. Sorry to post this twice, had put it in another thread but this seems like a better place for it Rob
You are correct. $10k is a lot and cannot be justified in terms of only gas savings. This is an early adopter technology purchase. It is amazingly cool to use and very satisfying. Thankfully about 1,500+ orders nationwide are allowing this technology to get out to private users and they can perfect it. Hopefully with volume the cost will drop to $5,000 or so.
It appears to me from reading the above quote in the PM article that they would see significant improvements just from including an EBH and grill blocking. This also appears to be a suggestion in a thread concerning the Hymotion with EBH. Do these modifications account for the higher mpgs that PC folks are seeing?
I still find it amazing that these people were only able to get 70 or so mpg. In warmer weather I've been able to hold 65-66 for several hundred miles of nonhighway driving and others in PC routinely do much better than that for an entire tank... I too would like to see this potentially great technology taken out of the hands of fleet testers and monitored/used by real life prius drivers who will give the general public a true representation of what the technology can deliver.
The EBH does help to cut the engine warm-up phase with Hymotion and gets you into EV mode. It is a minor improvement. I don't always use my EBH (I simply forget) and I am still solidly above 99.9 mpg at 500 miles on this tank of gas. The thing that hurts my overall average is when I get beyond the Hymotion battery range. Sometimes I do need more than 40 miles. My one-way trip might be 30 miles, and I could plug-in for an hour, so that gets my battery partially recharged. But the return trip will only get me half of the way home, then the Hymotion battery is empty and I am driving in stock Prius mode. THAT is what hurts my numbers. It has happened about 3 times in the past 3 weeks. If I was always within my Hymotion battery range and never entered stock Prius mode, I would never fall below 99.9 mpg.
+1 to everything PeakOil has stated. The EBH has helped me get into EV-mode quicker than normal, for a (slight) boost to initial mileage. I think this will become more of a factor once winter is here and temps go way down - this is probably where I'll see the most benefit. The biggest hit to my mileage is the fact that most of my driving exceeds the range of the L5 pack. I have the same issue with my work commute depleting the Hymotion battery before I get home and driving the last 5 miles in normal Prius mode, which affects my mileage negatively and brings me down to 70-80MPG for the home commute. I also do a lot of driving to Boulder and farther places, which also pull my average well below 100MPG. On my shorter commutes I have seen well above 100, with a high of 177 so far. Even though I have recently noticed an increase in the range of my L5 pack (I mentioned this in my Yet Another Hymotion Install thread), I still regularly drive beyond its range. I think it comes down to this: If your commute is within the range of the pack, 100-150MPG (depending on terrain and driving style) is very easy to achieve. Driving outside the range of the pack will most likely net you 70-100MPG, again depending on terrain and driving style. Believe me, I'm thrilled with the results I'm seeing and to me it has been well worth the expense to be one of the first with a real Plug-in Hybrid. Hopefully all the early adopters will help to bring the costs down to a more reasonable level so more people can afford to have this mod done, and to help manufacturers bring turn-key models to the public. Its great to be able to wave at gas stations as you drive by...:hand:
Hymotion update: 99.9 mpg for 639 miles Peak Oil Garage I have decided to stop using the reset button on my Prius consumption screen. I am just going to do one long term test so that we can clearly establish that the system can maintain 100+ mpg over the long haul. I live in a very hilly area, so if I can maintain a 100+ mpg average over a long period of time, then anyone can do it.
100 mpg? how about 1000 mpg? What a useless, sensationalistic, headline! If you have a big enough battery, and drive a short enough distance so that the gas engine does not turn on, then I could give you a 100,000 mpg car (I assume some of the gasoline would eventually evaporate along the way). Do these mag writers think we are morons? What is the TOTAL ENERGY COST per mile? That is what we need to know. In other words, on a long trip, what is the cost of electricity used to charge the battery AND gas used to supplement that. Last time I looked, my electricity was not coming in for free! Sheez!
That is a very complex calculation to make with a Plug-In Hybrid that uses two sources of energy for propulsion. There are basically 3 different scenarios: a) If most of the trips are short (under 25 miles) and less than 32 mph then you can go pure EV with the ICE never coming on. Then it is a simple calculation for electricity. I pay 8 cents per kwh. 5 kwh battery. 40 cents to recharge. That makes it about 1.6 cents per mile. b) at highway speeds where the ICE and battery are being used, then you can get 40 miles from the 40 cents of electricity. So it is about 1 penny per mile for electricity and add that to whatever MPG you are achieving. The MPG can vary in a wide range from 80 mpg to 200 mpg depending on how skilled you are. c) If you are doing long trips that exceed your battery range, then it gets even more complex to calculate. You have your initial 30-40 miles of Hymotion boosted range, then you have a regular Prius with 45-50 mpg. There is no simple answer "total energy cost per mile". A simple answer I have heard is: 100+ MPG plus 1 penny per mile in electricity. It also depends on the cost of electricity that you pay in your region.
biff44, if you are getting any significant portion of your miles from electricity, it is going to easily be 2x more efficient no matter how you dice the numbers. Electricity, even if made from coal, is going to beat gasoline/diesel in terms of efficiency every time.
A few of observations, as an owner of a Prius with a Hymotion conversion. 1) My wife and I seem to be getting about 90 MPG overall, for the driving we do, so far. 2) Driving style has a larger effect on gas mileage for a PHEV Prius than for a stock Prius, for a simple reason. The electrical system puts out a low, baseline level of power. Within the limits of the system (battery size, 34/41 mph limits), how much gasoline you use depends on how little power you demand above the electrically-supplied baseline. Your lowest level of gasoline use is zero, your highest is pretty much like a stock Prius, and what you get on average depends on the extent to which you keep the peak power demands down. So, the folks who got 60, I'm betting a) they drove with a heavy foot, and b) they're the type who can't get 40 out of a stock Prius. 3) But a lot of that variability in gas mileage is due to factors that are unique to the Prius conversion. It is, after all, a retrofit. A more powerful electrical side, fewer limits (34 mph/41 mph for EV mode), or for that matter doing this with a serial hybrid such as the proposed Volt -- all of those would allow you to use electricity for more of the average mile and would reduce the extent to which realized gas-only mileage varies with driving style. What I'm saying is the fact that some people manage to get mediocre mileage with a plug-in Prius shouldn't be used to judge the entire plug-in concept. What you're mostly seeing is the limits of a retrofit to a car that was not designed to be used this way. 4) Even with the limits, I really like the PHEV conversion. I particularly like driving around town in pure EV mode. 5) The Hymotion conversion never was likely to pay for itself (I figured I'd need 17 years of daily driving at $5/gallon gas to recoup the cost). But even with $2/gallon gas in the short run, battery cost might come down enough to make this a paying proposition. At $2/gallon, 10 years of daily battery depletion would save you close to $2K in fuel costs (depending on what you pay for electricity). So to put this in at the factory as a $2K option, that would pay for itself. It's not beyond the pale to think that sort of cost reduction may be feasible. The answer to cheap gas may be cheap batteries.
as much as they understand the Prius, they also missed a lot as well... 1) they acknowledge that the tank fills are not accurate and the MFD probably is. 2) ROI is not the point here 3) their numbers could be better but lets face it... NO MATTER HOW WELL YOU DRIVE, you can mitigate the numbers anyway you like....they got 70 mpg at 46º...heck i can make it 60 mpg no problem. the longer the drive, lesser is the impact hymotion provides. let me test drive the hymotion... lets see my numbers on my daily 15 mile RT commute....
