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Re: Prius seldom runs on batteries alone?

On Sun, 18 Feb 2007 18:42:01 -0700, "Michael Pardee"
<michaeltnull@cybertrails.com> wrote:

>"Bill Tuthill" <ccreekin@yahoo.com> wrote in message
>news:45d8eaaa@news.meer.net...
>> In alt.autos.toyota Chuck Olson <chuckolson01@removethiscomcast.net>
>> wrote:
>>>
>>> As most have said, the battery has to be charged above a specific
>>> threshold
>>> for the ICE to turn off. I have found that you also need to be in cruise
>>> control. Normal driving with foot on the accelerator just doesn't produce
>>> electric-only operation except at very slow side-street speeds. I guess
>>> that's because the Prius computer doesn't trust human beings to drive at
>>> a
>>> single fixed speed. My favorite EV speed in cruise control is 34 MPH.
>>
>> Interesting advice -- I'll have to try this.
>>
>>> To make sure the battery is charged and ready for EV operation, you need
>>> to
>>> apply fairly heavy braking from freeway speed.. Just slowing down slowly
>>> doesn't charge up the battery very efficiently. Unfortunately this kind
>>> of
>>> driving is uncomfortable for passengers, so don't do it unless you're
>>> alone.
>>> Also, make sure you brake before you hit a curve or encounter cross
>>> traffic.
>>
>> The B transmission setting is my favored way of doing this. I believe
>> it saves the brake pads, and it does not bother my passengers.
>>
>
>I recommend just using the brakes - they don't normally use friction above
>12 mph or so. The brakes on my 106K mile Prius are nearly at original
>thickness.
>
>"B" mode is somewhat less efficient than using the brakes, because it
>reduces regeneration. That doesn't make a huge difference, but just braking
>is easier, too. "B" mode is useful on long downhills, especially if the drop
>is more than 2000 ft. When the battery is fully charged the friction brakes
>start getting wear.

More critically, the brakes will overheat and fail if used to control
speed on a long/steep descent.

Re: What about the mileage!?!?!?!?!

Re: Prius seldom runs on batteries alone?

In article <45d65311@news.meer.net>, Bill Tuthill <ccreekin@yahoo.com>
wrote:

> Driving 75-80 mph from San Jose to Los Angeles, my wife got about
> what you UK drivers get. Short trips are far worse for Prius mileage
> than excessive speeds.
It's stop and go driving where the hybrid technology gains, there's
little or no gain with steady high speed driving.
Sounds like it's not working properly.

Re: Prius seldom runs on batteries alone?

"who" <i@notaspammer.net> wrote in message
news:i-1C3475.00542219022007@news.telus.net...
> In article <45d65311@news.meer.net>, Bill Tuthill <ccreekin@yahoo.com>
> wrote:
>
>> Driving 75-80 mph from San Jose to Los Angeles, my wife got about
>> what you UK drivers get. Short trips are far worse for Prius mileage
>> than excessive speeds.
> It's stop and go driving where the hybrid technology gains, there's
> little or no gain with steady high speed driving.
> Sounds like it's not working properly.
-----
Barometric pressure and fuel quality can make either city or highway fuel
efficiency flip flop. On level ground doing 101 miles an hour my digital
display says real time fuel economy above 35 but less than 45 mpg. I
hesitate to believe a traditional non-hybrid would even come close to that
fuel economy range at that speed. So, when someone tells their husband they
only saw such and such fuel efficiency you can sure as hell bet they drove
much faster than what they said they did, or their range of speed was more
like an up and down 60 to 80. Can't place blame on the car.
mark_
-----

Re: What about the mileage!?!?!?!?!

"You guess" <jackj^remove^180@adelphia.net> wrote in message
news:68uht2linmu47orlobi02m6pebhoq1tq7q@4ax.com...
> On Sun, 18 Feb 2007 14:23:29 -0700, "Michael Pardee"
> <michaeltnull@cybertrails.com> wrote:
>
>>"You guess" <jackj^remove^180@adelphia.net> wrote in message
>>news:1sogt2d22bgfhisiksaapvu88dnls9itro@4ax.com. ..
>>> On Sun, 18 Feb 2007 07:14:04 -0700, "Michael Pardee"
>>> <michaeltnull@cybertrails.com> wrote:
>>>
>>>>
> Mike,
>
> This is going to be my last on this subject. I'm not going to
> convince you and you're not going to convince me.
>
> You don't point to any hard info on increased efficiency, you just say
> it is so. I have read where some of the Toyota and Honda hybrid
> customers are not happy. They are not getting the mileage the sicker
> says they should. They aren't missing the figure by 4 or 5%, they're
> missing it by 25 to 30%. They have gotten some lawyer to file a class
> action suit. No great challenge that and filing a law suit doesn't
> prove anything, I grant you. But it does show that not everyone is
> tickled pink with their hybrid.
>
> I own a 2006 Corolla. It has a small IC engine and gets good mileage
> while delivering reasonable performance, that's why I bought it. An
> honest 35 to 37 mpg on the highway at 60 mph. Mileage around town is
> less but still in the mid 20's. The reason why it gets better mileage
> than my Mercury Grand Marquis is because it's small and light and
> doesn't have as much engine. Two of the Toyota engines still wouldn't
> make the V8 that is in my Merc.
>
> The Merc gets around 28 to 29 mpg at 60 mph but only about 15 to 17
> mpg around town. The Merc has 2 major things working against it on
> mileage, weight and air resistance. It's about as stream-lined as a
> book case and weighs almost as much as 2 Corolla's.
>
> What I'm trying to point out is that I could never get the Mercury to
> get the same mileage as the Corolla. If I put the engine and drive
> train from my Corolla into my Mercury, it wouldn't get anywhere near
> the mileage of the Corolla. But the performance would be a lot worse
> than either of them furnish now. Adding an electric motor, batteries
> and the control circuitry of a hybrid to the existing drive train of
> the Mercury would only further decrease the mileage.
>
> I also will never get the Corolla to be as comfortable as the Mercury.
> I can drive the Grand Marquis for hours without getting tired but the
> Corolla has me squirming around in less than an hour.
>
> You mentioned that you decided while you were still in high school
> that automobiles were inefficient and I agree. But adding more
> inefficient elements to the mix won't make for greater efficiency.
>
> I could be a smart a-- here and say that some folks believe in Global
> Warming, that CFC's cause the Ozone hole over the South Pole, the
> Easter bunny and Santa Claus....but I won't. hehehe
>
> I think I'll go mix some aged ethanol from Tennessee with water and
> ice now. I've enjoyed the discussion but I'm not going to respond to
> anything else on the subject.
>
> Thanks
> Jack
>
>
As an owner of two Prius, I am very happy. The two cars together have
roughly the same fuel consumption of the 300ZX I traded in, and they are a
joy to drive (I love maneuverability). Most of all, they are the most
reliable cars I've ever had, by a wide margin. To each their own.

BTW... I'm with you on global warming and CFCs, but you're right - let's not
get that started. Have you seen NASA's findings on polar ozone depletion at
http://tinyurl.com/2lkn42 ? Especially interesting is Table 1 on page 59 of
the .doc version.

Don't get the Easter Bunny mad at us, though. I need the chocolate eggs.

Mike

Re: Prius seldom runs on batteries alone?

In article <d900$45d924ca$47c2b532$16838@msgid.meganewsserver s.com>
rokigawaATtristarassociatesDOTcom "Ray O" writes:

> IIRC, the minimum speed to set cruise control on a Toyota is around 25 MPH,
> below which, the CC will not set and the memory clears. I can set the CC on
> our 3 Toyotas at 30 MPH, which I do in areas where the police often sit ;-)

Have to break the habit of a lifetime and agree with Ray. <g> My
Prius definitely allows me to set 30mph. Haven't tried any lower
(except maybe 29mph).
--
Andrew Stephenson

Re: Prius seldom runs on batteries alone?

In article <i-1C3475.00542219022007@news.telus.net>
i@notaspammer.net "who" writes:

> In article <45d65311@news.meer.net>, Bill Tuthill <ccreekin@yahoo.com>
> wrote:
>
> > Driving 75-80 mph from San Jose to Los Angeles, my wife got about
> > what you UK drivers get. Short trips are far worse for Prius mileage
> > than excessive speeds.

> It's stop and go driving where the hybrid technology gains, there's
> little or no gain with steady high speed driving.
> Sounds like it's not working properly.

I read Bill's remarks as meaning "really short trips", like those
which don't warm up the engine properly and give the mpg time for
"recovery".
--
Andrew Stephenson

Re: Re:What about the mileage!?!?!?!?!

"We need more reliable, clear numbers" Andrew Stephenson

"I agree, we can wave our hands around and make points both ways, but
without real comparative numbers (which I for one do not have) it is all
just speculation." Tomes

So basically; No one has any experimental facts to support any conclusion,
or theory.

"Polymer Science Engineer here. As a physicist, you might have run across
situations where an answer comes through discussion, as well as through a
straight answer. The discussion is what occurs here and this is the
normal course of events in this Newsgroup. This is not a flaw, it is a
feature." Patience Grasshopper

So, this group is just a bunch of old farts shooting the breeze.

For the record, the way I learned science; discussion, speculations,
conjectures, 'shooting the breeze' are all excellent ways to think about
nature, formulate theories and suggest experiments to test such theories.
But as mentor of mine once said, physics is different from logic,
mathematics, and theology, in that we run experiments.

Clearly no one has installed an EV button, and utililized it in a consistent
fashion (for example turning it on when you anticipate driving for less than
2 miles) and measured the resulting mileage.

Finally, for what its worth to those of you looking for 'hard numbers'; our
first tankfull resulted in 44mpg (US gallons, not imperial gallons, of 87
octane regular gasoline), in a mixed highway and city (red lights) commute
across gentle small hills of 75 miles per day. I also read that the US EPA
will relabel the Prius from 60 city 51 hwy to 44 hwy this coming summer.

thank you for your comments

-princeton

"Tomes" <askme@here.net> wrote in message
news:m2LBh.3283$tD2.1902@newsread1.news.pas.earthl ink.net...
> R:
> Polymer Science Engineer here. As a physicist, you might have run across
> situations where an answer comes through discussion, as well as through a
> straight answer. The discussion is what occurs here and this is the
> normal course of events in this Newsgroup. This is not a flaw, it is a
> feature.
>
> Patience Grasshopper.
>
>
> "R PRINCETON" <rlanni@access4less.net> wrote in message
> news:lEJBh.3207$tD2.1013@newsread1.news.pas.earthl ink.net...
> >" Did you actually READ all the responses, to your questions and
> > the others you no doubt found when you no doubt Googled on the
> > recent traffic in this NG, and THINK about them?"
> >
> > YES I DID. I have googled, I have read; that's why I included the
> > reference
> > to coal powered electric plants. (Of course, being an old fart, I may
> > have
> > missed "IT".) What I concluded is that in other countries the EV switch
> > is
> > provided by Toyota. Why? Is it because using it will improve gas
> > mileage?
> >
> > I have noticed that the ICV in my Prius runs way more often than I
> > expected,
> > and for more than just recharging the batteries. The cute animation in
> > the
> > LCD display clearly shows that most of the time the ICV is powering the
> > wheels, i.e., providing more power than the electric motor by itself can
> > provide. I am suspicious that this is done so as to improve the
> > Prius's
> > "drivability" in the US; i.e., greater acceleration. Us Americans are
> > accustomed to "tearing" away from the traffic light. While in other
> > countries slower accelerating vehicles are more the norm. I have also
> > noticed that when I take my foot off the gas after a stop the Prius
> > 'creeps'
> > just like a normal automatic transmission ICV only vehicle (something
> > that a
> > manual transmission driver does not need). Again, a feature to improve
> > drivability at the expense of mileage.
> >
> > Given that it is well known that jack-rabbit starts result in
> > significantly
> > lower gas mileage vs a more constant power curve, I would be willing to
> > accept slower starts for more gas mileage. Ergo, my interest in an EV
> > switch. It is also well known that an ICV engine runs much more
> > efficiently at a specific RPM where it generates maximum torque per
> > gallon
> > of gas; so it would make sense to operate the ICV at that speed
> > exclusively
> > for recharging the batteries and never for pulling the vehicle. That is
> > why
> > railroads use diesel-electric engines as opposed to diesel only engines.
> > (Why tractor trailers don't also do this is a mystery to me.) (Yes
> > there is
> > a point where the diesel engine generates electricity as fast as the
> > electric drive wheels consume it and that point varies with each engine
> > based upon its expected use.)
> >
> > So back to my original question: Has anyone installed an EV switch and
> > used
> > it long enough (a year or more) and noticed a marked improvement in gas
> > mileage (10% or more).
> >
> > (Why 10%? Because that show much I improved my Bonneville's mileage
> > simply
> > by using my cruise control as much as possible to accelerate the vehicle
> > and
> > maintain a more constant speed than I myself could do on the highway.)
> >
> > BTW; I am a Physicist by training. I am not interested in
> > "Implications" I
> > want facts!
> >
> >
> > -thank you
> >
> >
> > "Andrew Stephenson" <ames@deltrak.demon.co.uk> wrote in message
> > news:1171719278snz@deltrak.demon.co.uk...
> >> In article <cvzBh.3066$tD2.710@newsread1.news.pas.earthlink.n et>
> >> rlanni@access4less.net "R PRINCETON" writes:
> >>
> >> > Unbelievable! 11 answers and counting and no-one answers my
> >> > original
> >> > question! Are you all a bunch of politicians!?!?!?!
> >> >
> >> > OK, enough ranting....
> >> >
> >> > Ignoring, increased wear and tear on the batteries or engine, total
> > energy
> >> > equations involving my old coal powered power plant; and any
> > disturbances in
> >> > subspace temporal harmonics....
> >> >
> >> > DID THE EV only switch increase peoples mileage? and by how much?
> >>
> >> Did you actually READ all the responses, to your questions and
> >> the others you no doubt found when you no doubt Googled on the
> >> recent traffic in this NG, and THINK about them?
> >>
> >> The implication was that it's not worth doing. The car is set
> >> to care for itself and the battery. "Mileage" is another word
> >> for "efficiency" in this context. Greater efficiency turns on
> >> making better overall use of the fuel put into the tank. Read
> >> my past posts on my EV experiments (see recent Google). EV is
> >> purely there to solve local problems unrelated to efficiency.
> >>
> >> GOT IT? Thank you. That ends this party political broadcast.
> >> --
> >> Andrew Stephenson
> >>
> >
> >
>
>

Re: Prius seldom runs on batteries alone?

On Feb 18, 10:56 pm, "Ray O" <rokigawaATtristarassociatesDOTcom>
wrote:
> "Tomes" <a...@here.net> wrote in message
> IIRC, the minimum speed to set cruise control on a Toyota is around 25 MPH,
> below which, the CC will not set and the memory clears. I can set the CC on
> our 3 Toyotas at 30 MPH, which I do in areas where the police often sit ;-)

US 2004 Owner's Manual, section 2-6 "Operation of Instruments and
Controls, "POWER switch, transmission, and parking brake," "Cruise
Control," page 141:
"The cruise control allows you to cruise the vehicle at a desired
speed over 40
km/h (25 mph) even with your foot off the accelerator pedal."

Myself, I've been able to set the cruise control at 24mph, so I'd
guess that the kph is the more important trigger there...

Re: Re:What about the mileage!?!?!?!?!

In article <VDjCh.4004$tD2.98@newsread1.news.pas.earthlink.ne t>
rlanni@access4less.net "R PRINCETON" writes:

> Clearly no one has installed an EV button, and utililized it in
> a consistent fashion (for example turning it on when you
> anticipate driving for less than 2 miles) and measured the
> resulting mileage.

Forgive my bluntness, Mister Physicist, but it seems called for.
Either you've not actually been paying attention to what we have
been posting, or you're an idiot, or some mixture of both. Data
to hand indicate the third condition, plus ignorance and ego.

When are you going to catch on that the Prius "EV" mode does not
allow one to use it as you describe? Yes, you could engage "EV"
for (say) a series of very short trips. But sooner or later the
car's control system would decide the big battery had discharged
deeply enough to warrant flipping out of "EV" mode and firing up
the petrol engine for a recharge. It does that whether you like
it or not, to safeguard the battery (not to mention your ability
to drive the car). The length of run just isn't worth it for an
average user, the person for whom Toyota make this car. IOW, as
you've been told, repeatedly: THE CAR IS IN CHARGE OF STUFF LIKE
THAT -- NOT YOU.

If you don't like that you already know one solution. The other
is: shun this current Prius generation entirely -- along with us
farts here shooting the breeze. I especially like the last bit.

(Trolls. Bah. You just can't get classy/clever ones any more.)
--
Andrew Stephenson

Re: Re:What about the mileage!?!?!?!?!

"R PRINCETON" <rlanni@access4less.net> wrote in message
news:VDjCh.4004$tD2.98@newsread1.news.pas.earthlin k.net...
> "We need more reliable, clear numbers" Andrew Stephenson
>
> "I agree, we can wave our hands around and make points both ways, but
> without real comparative numbers (which I for one do not have) it is all
> just speculation." Tomes
>
> So basically; No one has any experimental facts to support any
> conclusion,
> or theory.
>
> "Polymer Science Engineer here. As a physicist, you might have run
> across
> situations where an answer comes through discussion, as well as through
> a
> straight answer. The discussion is what occurs here and this is the
> normal course of events in this Newsgroup. This is not a flaw, it is a
> feature." Patience Grasshopper
>
> So, this group is just a bunch of old farts shooting the breeze.

Sometimes. Other times we get experts weighing in as well. It is a sum
of all of it.

>
> For the record, the way I learned science; discussion, speculations,
> conjectures, 'shooting the breeze' are all excellent ways to think about
> nature, formulate theories and suggest experiments to test such
> theories.
> But as mentor of mine once said, physics is different from logic,
> mathematics, and theology, in that we run experiments.
>
> Clearly no one has installed an EV button, and utililized it in a
> consistent
> fashion (for example turning it on when you anticipate driving for less
> than
> 2 miles) and measured the resulting mileage.

Yep, looks like we are on the same page here. We have not run this
particular test and we have not found it published either, so we are back
to our discussion, speculations and conjectures. It is what we have at
hand.

>
> Finally, for what its worth to those of you looking for 'hard numbers';
> our
> first tankfull resulted in 44mpg (US gallons, not imperial gallons, of
> 87
> octane regular gasoline), in a mixed highway and city (red lights)
> commute
> across gentle small hills of 75 miles per day. I also read that the US
> EPA
> will relabel the Prius from 60 city 51 hwy to 44 hwy this coming summer.
>
> thank you for your comments
>
> -princeton

We get about the same MPG here between Flemington and Bound Brook NJ and
around here. I read that the whole EPA mileage rating system is being
revised to project more realistic numbers, rather than their
pie-in-the-sky utopian figures that they have been putting out for years.
Pegging the Prius at 44 highway is realistic from my experience.
Tomes

Re: Prius seldom runs on batteries alone?

"Ray O" <rokigawaATtristarassociatesDOTcom> wrote in message
news:d900$45d924ca$47c2b532$16838@msgid.meganewsse rvers.com...
> "Tomes" <askme@here.net> wrote in message
> news:TT8Ch.3218$_73.2885@newsread2.news.pas.earthl ink.net...
> <snipped>
>> I guess every manufacturer does it differently. Honda cruise control
>>> will remember the speed until you shut off the engine or at least the
>>> CC master switch. However, the CC cannot be engaged at speeds below
>>> ~20 mph. I think they want to prevent someone from inadvertently
>>> engaging the CC and having the car jump from a stationary position.
>>>
>>>
>> That's another thing. The minimum speed thing on CC. Why not let it
>> start at 10 MPH or so? I use it a lot when the speed limit is, say,
>> 40MPH. It prevents me from accidentally going faster, which I can so
>> easily do. But I cannot use it for a speed limit of 30, which we have
>> around here on windy rural back roads. I would really like to set it
>> at 33 and just let it go, but alas I cannot. I perceive this as
>> another flaw. (The Jeep is the same way, engages at about 35).
>> Tomes
> IIRC, the minimum speed to set cruise control on a Toyota is around 25
> MPH, below which, the CC will not set and the memory clears. I can set
> the CC on our 3 Toyotas at 30 MPH, which I do in areas where the police
> often sit ;-)
> --
>
> Ray O
> (correct punctuation to reply)
>
Yeah, I just looked it up and it is supposed to be 24 MPH on the Prius.
That's better than I thought. But still, I would like to see a minimum of
'already engaged in forward motion' rather than any minimum.
Tomes

Re: Prius seldom runs on batteries alone?

"Andrew Stephenson" wrote ...
> "who" writes:
>> Bill Tuthill wrote:
>>
>> > Driving 75-80 mph from San Jose to Los Angeles, my wife got about
>> > what you UK drivers get. Short trips are far worse for Prius mileage
>> > than excessive speeds.
>
>> It's stop and go driving where the hybrid technology gains, there's
>> little or no gain with steady high speed driving.
>> Sounds like it's not working properly.
>
> I read Bill's remarks as meaning "really short trips", like those
> which don't warm up the engine properly and give the mpg time for
> "recovery".

I read it the same way. The first few miles are always killer miles.
Tomes

Re: Prius seldom runs on batteries alone? - B Mode

"Ray O" wrote ...
> "Tomes" wrote ...
> <snipped>>
>>> "B" mode is somewhat less efficient than using the brakes, because it
>>> reduces regeneration. That doesn't make a huge difference, but just
>>> braking is easier, too. "B" mode is useful on long downhills,
>>> especially if the drop is more than 2000 ft. When the battery is fully
>>> charged the friction brakes start getting wear.
>>>
>>
>> OK, I know I have read this, and what I have read has not always been
>> the same thing. In your words, what exactly does 'B' mode do and how?
>> Thanks.
>> Tomes
>
> According to the faq section at www.toyota.com:
> "B" is the position for engine braking. Engine braking assists the
> brakes in slowing the vehicle. It serves a similar function to
> downshifting on an automatic transmission. This position is intended
> for going down long declines, and utilizes the electric motor to slow
> the vehicle and regenerate electricity. For more information please
> reference Section 2 of your Owner's Manual.
>
OK, that's what I thought. It uses the electric motor in reverse to
generate electricity stored in the batteries. The IC engine remains out
of the picture. Now my next question is does it generate more or less
than in normal mode?
Tomes

Re: Prius seldom runs on batteries alone? - B Mode

"Tomes" <askme@here.net> wrote in message
news:QmnCh.3424$x74.109@newsread4.news.pas.earthli nk.net...
> "Ray O" wrote ...
>> "Tomes" wrote ...
>>
>> According to the faq section at www.toyota.com:
>> "B" is the position for engine braking. Engine braking assists the
>> brakes in slowing the vehicle. It serves a similar function to
>> downshifting on an automatic transmission. This position is intended for
>> going down long declines, and utilizes the electric motor to slow the
>> vehicle and regenerate electricity. For more information please
>> reference Section 2 of your Owner's Manual.
>>
> OK, that's what I thought. It uses the electric motor in reverse to
> generate electricity stored in the batteries. The IC engine remains out
> of the picture. Now my next question is does it generate more or less
> than in normal mode?
> Tomes
>

I think that's backward - it dumps energy into turning the engine rather
than into the battery. Maybe MRV can explain it more clearly. She does that
sort of thing so well :-) People who have monitored the battery current with
the Ecrostech Miniscanner (http://tinyurl.com/2yvbrx) report less
regeneration in "B." I've never actually checked myself, but if you want
numbers I can do that.

Mike