Re: Prius seldom runs on batteries alone?
 

"Gordon McGrew" <RgEmMcOgVrEew@mindspring.com> wrote in message
news:vmeit215ohfgf3gdokiga98fajpo8787f9@4ax.com...
> On Sun, 18 Feb 2007 18:42:01 -0700, "Michael Pardee"
> <michaeltnull@cybertrails.com> wrote:
>>
>>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.

Possibly. The brakes are not especially big, and here in the States the rear
brakes are drum type. I understand in Europe they are 4-wheel disks. Anyway,
use "B" for long descents.

Mike

Re: Prius seldom runs on batteries alone?
 

On Mon, 19 Feb 2007 08:54:22 GMT, who <i@notaspammer.net> wrote:

>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.

The gain in highway efficiency is in the ability to use a lower output
engine due to the availability of supplemental power from the battery.
When operating at cruising speed, the engine will be running at a
higher % power level which is more efficient. In this mode, the
electrical drive line saves fuel by merely being there if you need it.

Re: Prius seldom runs on batteries alone?
 

In alt.autos.toyota Michael Pardee <michaeltnull@cybertrails.com> wrote:
>>>
>>> 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.

Are you sure about this 12 mph or so? It sounds like I'm hearing
pad friction at higher speeds.

>>> "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.

How do you know it reduces regeneration using B instead of braking?
Do you mean braking is more radical (more force) yielding more regenerated
power? Guess I'm used to manual transmission and want something to do.
But I see the battery charging quickly when the Prius is in B.

> Possibly. The brakes are not especially big, and here in the States
> the rear brakes are drum type. I understand in Europe they are
> 4-wheel disks. Anyway, use "B" for long descents.

I wonder if the US Touring model also has 4-wheel disk brakes?

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

"Michael Pardee" <michaeltnull@cybertrails.com> wrote in message
news:_L6dnUQ8KennuUfYnZ2dnUVZ_qyjnZ2d@sedona.net.. .
> "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
>
Thanks, interesting reading there. So now I am re-understanding this as
follows: In B mode it spins the IC engine without starting the engine,
wasting off excess energy in that spinning. What is not explained to me
yet (his section of How B Mode Works was truncated off) is does it
generate electricity in this engine spinning (the reverse of how it starts
the engine up all the time)?

I think that I gleaned from this stuff that it makes less electricity in B
mode due to the spinning waste.
Tomes

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

"Tomes" <askme@here.net> wrote in message
news:yntCh.4267$tD2.2584@newsread1.news.pas.earthl ink.net...
> "Michael Pardee" <michaeltnull@cybertrails.com> wrote in message
> news:_L6dnUQ8KennuUfYnZ2dnUVZ_qyjnZ2d@sedona.net.. .
>> "Tomes" <askme@here.net> wrote in message
>> news:QmnCh.3424$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.
>>
> Thanks, interesting reading there. So now I am re-understanding this as
> follows: In B mode it spins the IC engine without starting the engine,
> wasting off excess energy in that spinning. What is not explained to me
> yet (his section of How B Mode Works was truncated off) is does it
> generate electricity in this engine spinning (the reverse of how it
> starts the engine up all the time)?
>
> I think that I gleaned from this stuff that it makes less electricity in
> B mode due to the spinning waste.

OK I found this other link that actually explains it pretty well, if
anyone cares :-).
http://www.techno-fandom.org/~hobbit/cars/b-mode.html
Here is a bit copied out of that:
......Enter "B" mode. As in, "trucks use lower gear". By forcing the
wheels
to spin the engine and pump air, a good deal of that energy can be turned
to heating the air going through the engine instead of heating the brake
parts. Since fresh air is always coming into the engine, having it leave
as much warmer air provides a convenient place to dump excess energy.
In a conventional car the wheels push the engine around through the
transmission, but the Prius needs to help that process out a little bit
by actually having its combination of electric motors spin the engine.
In this case, the valve-timing in the Prius engine is advanced to increase
the amount of air taken in and the suction against the throttle flap --
which
uses much more energy than the coasting-in-"D" scenario above......

There is a lot more there that I have not copied here, but in addition to
capturing some of the energy, it is spinning it off in B mode.

Bottom line is to not use it in the hopes of saving more energy.
Tomes

Re: Prius seldom runs on batteries alone?
 

"Bill Tuthill" <ccreekin@yahoo.com> wrote in message
news:45da5ba3@news.meer.net...
> In alt.autos.toyota Michael Pardee <michaeltnull@cybertrails.com> wrote:
>>>>
>>>> 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.
>
> Are you sure about this 12 mph or so? It sounds like I'm hearing
> pad friction at higher speeds.
>
>>>> "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.
>
> How do you know it reduces regeneration using B instead of braking?
> Do you mean braking is more radical (more force) yielding more
> regenerated
> power? Guess I'm used to manual transmission and want something to do.
> But I see the battery charging quickly when the Prius is in B.
>
>> Possibly. The brakes are not especially big, and here in the States
>> the rear brakes are drum type. I understand in Europe they are
>> 4-wheel disks. Anyway, use "B" for long descents.
>
> I wonder if the US Touring model also has 4-wheel disk brakes?
>
Bill - read this link regarding what it does in B Mode:
http://www.techno-fandom.org/~hobbit/cars/b-mode.html
It answered a bunch of questions for me about 5 minutes ago. Basically, B
mode wastes off excess energy by spinning the IC engine. Read on....
Tomes

Re: Prius seldom runs on batteries alone?
 

"Tomes" <askme@here.net> wrote in message
news:7fnCh.3419$x74.1115@newsread4.news.pas.earthl ink.net...
<snipped>

> 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
>

The minimum speed for cruise control has been 25 MPH since cruise control
first appeared on Toyotas. My guess is that speed was chosen to prevent
someone trying to use it in stop-and-go driving.
--

Ray O
(correct punctuation to reply)

Re: Prius seldom runs on batteries alone?
 

In alt.autos.toyota Tomes <askme@here.net> wrote:
> Bill - read this link regarding what it does in B Mode:
> http://www.techno-fandom.org/~hobbit/cars/b-mode.html
> It answered a bunch of questions for me about 5 minutes ago. Basically, B
> mode wastes off excess energy by spinning the IC engine. Read on....

Thanks Tomes! That was illuminating and contained many surprises,
e.g. "When accelerating... D and B produce the same behavior."

Do you know about "the Great Database Fire" that took out Priuschat?
A similar thing happened to one of the chat sites I visit, BoaterTalk.
That's one big downside of chat websites versus group (Usenet) news.
OTOH I suppose Google could discontinue groups so we wouldn't be able
to search back posts any longer.

Re: Prius seldom runs on batteries alone?
 

"Bill Tuthill" <ccreekin@yahoo.com> wrote in message
news:45db349c@news.meer.net...
> In alt.autos.toyota Tomes <askme@here.net> wrote:
>> Bill - read this link regarding what it does in B Mode:
>> http://www.techno-fandom.org/~hobbit/cars/b-mode.html
>> It answered a bunch of questions for me about 5 minutes ago.
>> Basically, B
>> mode wastes off excess energy by spinning the IC engine. Read on....
>
> Thanks Tomes! That was illuminating and contained many surprises,
> e.g. "When accelerating... D and B produce the same behavior."
>
> Do you know about "the Great Database Fire" that took out Priuschat?
> A similar thing happened to one of the chat sites I visit, BoaterTalk.
> That's one big downside of chat websites versus group (Usenet) news.
> OTOH I suppose Google could discontinue groups so we wouldn't be able
> to search back posts any longer.
>
You are welcome, glad to be able to actually contribute something other
than opinion. It is a pretty good read, I just hope it is all correct
:-).

What is this Priuschat? Or is the question what _was_ Priuschat?
Tomes

Re: Prius seldom runs on batteries alone?
 

In alt.autos.toyota Tomes <askme@here.net> wrote:
>>>
>>> http://www.techno-fandom.org/~hobbit/cars/b-mode.html

The page you posted is on a website http://www.techno-fandom.org/~hobbit
with a lot of interesting stuff. I didn't have much time to investigate
but he/she writes (and supports with a picture):

"With summer gasoline in good weather, I have no trouble getting
70 MPG on a country road with light traffic."

I can't wait for summer! Getting > 50 MPG is more fun than driving.

> You are welcome, glad to be able to actually contribute something other
> than opinion. It is a pretty good read, I just hope it is all correct
> :-). What is this Priuschat? Or is the question what _was_ Priuschat?

Priuschat.com is a blog site, or whatever you call those things,
where you can post questions and answers. It seems to be the best,
and one of the most active, although there are others.

I find Yahoo groups to be a giant PITA, so I completely abandoned them,
but Yahoo has about a dozen Prius or hybrid "news" groups.

Re: Prius seldom runs on batteries alone?
 

"Bill Tuthill" > wrote ...
> Tomes wrote:
>>>>
>>>> http://www.techno-fandom.org/~hobbit/cars/b-mode.html
>
> The page you posted is on a website http://www.techno-fandom.org/~hobbit
> with a lot of interesting stuff. I didn't have much time to investigate
> but he/she writes (and supports with a picture):
>
> "With summer gasoline in good weather, I have no trouble getting
> 70 MPG on a country road with light traffic."
>
> I can't wait for summer! Getting > 50 MPG is more fun than driving.
>
>> You are welcome, glad to be able to actually contribute something other
>> than opinion. It is a pretty good read, I just hope it is all correct
>> :-). What is this Priuschat? Or is the question what _was_ Priuschat?
>
> Priuschat.com is a blog site, or whatever you call those things,
> where you can post questions and answers. It seems to be the best,
> and one of the most active, although there are others.
>
> I find Yahoo groups to be a giant PITA, so I completely abandoned them,
> but Yahoo has about a dozen Prius or hybrid "news" groups.
>
I gave up on Yahoo groups quickly as well. I will check out this
Priuschat thingy. Thanks. I also agree about the summer thing....
Tomes

Re: Prius seldom runs on batteries alone?
 

On 20 Feb 2007 09:49:16 -0800, Bill Tuthill <ccreekin@yahoo.com>
wrote:

>In alt.autos.toyota Tomes <askme@here.net> wrote:
>> Bill - read this link regarding what it does in B Mode:
>> http://www.techno-fandom.org/~hobbit/cars/b-mode.html
>> It answered a bunch of questions for me about 5 minutes ago. Basically, B
>> mode wastes off excess energy by spinning the IC engine. Read on....
>
>Thanks Tomes! That was illuminating and contained many surprises,
>e.g. "When accelerating... D and B produce the same behavior."

Gee, wouldn't a set of Dynamic Braking Resistors in front of the
radiator (or a separate cooling fan) work just as effectively and not
sit there spinning the engine?

Just dump the excess energy as heat without wearing down the brakes,
the motor-generator or the engine - It's worked on Diesel Electric
Locomotives for 60+ years...

--<< Bruce >>--

Re: Prius seldom runs on batteries alone?
 

On Feb 20, 5:59 pm, Bill Tuthill <ccree...@yahoo.com> wrote:
> I find Yahoo groups to be a giant PITA, so I completely abandoned them,
> but Yahoo has about a dozen Prius or hybrid "news" groups.

If I may ask, what did you find to be the problem? Other than the
adverstisements (which also plague most other Prius sites), what was
the issue(s)? The Yahoo!Groups are mainly email discussion lists, but
you do not have to read/receive/post messages via email but can be a
web-only subscriber. Yahoo has changed the email formatting and web
message archives lately, so if you're a fan of threaded responses
(among other things) you might be happy...

-Michelle, moderator or owner of quite a few Yahoo!Groups...

In general, I recommend (though I'm a moderator on only 2 of those
listed):
http://autos.groups.yahoo.com/group/toyota-prius/
http://autos.groups.yahoo.com/group/Prius-2G/
http://autos.groups.yahoo.com/group/2007_Prius/
http://www.priusonline.com/
http://www.priuschat.com/
http://www.greenhybrid.com/discuss/
http://www.cleanmpg.com/forums/

or the more appropriate usenet newsgroup: alt.autos.toyota.prius

Re: Prius seldom runs on batteries alone?
 

In alt.autos.toyota Michelle <mrv@kluge.net> wrote:
>
>> I find Yahoo groups to be a giant PITA, so I completely abandoned them.
>
> If I may ask, what did you find to be the problem? Other than the
> adverstisements (which also plague most other Prius sites), what was
> the issue(s)?

Advertising was only a tiny issue. The big problem for me was the lack of
threaded presentation. One nice thing about photo.net, a non-Usenet BB
I still read, is that all posts on a given topic are on the same webpage,
so you only download once per topic. Even with a broadband Internet link,
Yahoo groups are just too slow for me.

> The Yahoo!Groups are mainly email discussion lists, but you do not
> have to read/receive/post messages via email but can be a web-only
> subscriber. Yahoo has changed the email formatting and web message
> archives lately, so if you're a fan of threaded responses (among
> other things) you might be happy...

Aha, maybe I should check it out again. The problem with subscribing
by email is that Yahoo groups were, maybe stilla re, a huge source
of spam, so giving my good email address was inadvisable, and my bad
email address (ccreekin at Yahoo) is slow and hard to navigate; it is
basically unusable during the business day.

> I recommend (though I'm a moderator on only 2 of those listed):
> http://autos.groups.yahoo.com/group/toyota-prius/
> http://autos.groups.yahoo.com/group/Prius-2G/
> http://autos.groups.yahoo.com/group/2007_Prius/ ...

From reading the Yahoo descriptions, I could not tell which to read.
The last two sound like exactly the same thing. Any hints?

> or the more appropriate usenet newsgroup: alt.autos.toyota.prius

My news service doesn't get that one (yet). Thanks, Michelle!

Re: Prius seldom runs on batteries alone?
 

On Feb 21, 12:23 pm, Bill Tuthill <ccree...@yahoo.com> wrote:
> Advertising was only a tiny issue. The big problem for me was the lack of
> threaded presentation. One nice thing about photo.net, a non-Usenet BB
> I still read, is that all posts on a given topic are on the same webpage,
> so you only download once per topic. Even with a broadband Internet link,
> Yahoo groups are just too slow for me.

I would suggest either a digest format (probably the New which is
easier to reply through, but the "traditional" is now threaded as
well), or choose the "no email" subscription option and just read/post
through the message archives at the web site. In the message
archives, "group by topic" may work for you.

> Aha, maybe I should check it out again. The problem with subscribing
> by email is that Yahoo groups were, maybe stilla re, a huge source
> of spam, so giving my good email address was inadvisable, and my bad
> email address (ccreekin at Yahoo) is slow and hard to navigate; it is
> basically unusable during the business day.

Although the groups I listed are all moderated, that will keep the
spam down on the lists, but doesn't keep the spammers from joining...
Yahoo doesn't make available the actual email address of a poster or a
member on the website, but since it is an email list if you post your
address will go out to those subscribed in that fashion... So it is
possible that some spammers may join, just to scrape addresses out of
the daily digests. A throwaway account or a good spam filter may help
here.

> > I recommend (though I'm a moderator on only 2 of those listed):
> >http://autos.groups.yahoo.com/group/toyota-prius/
> >http://autos.groups.yahoo.com/group/Prius-2G/
> >http://autos.groups.yahoo.com/group/2007_Prius/ ...
>
> From reading the Yahoo descriptions, I could not tell which to read.
> The last two sound like exactly the same thing. Any hints?

toyota-prius (remember the dash!) is the older group of all the ones I
listed (including PC and PoL), having migrated over to a Yahoo!Group
when Yahoo bought out eGroups. Discussion is open to all models of
Prius (since they share many parts in common). These days I'd say
that NHW11 and NHW20 traffic is about equal, and the occasional NHW10
traffic is diverted to its own group (Mk1_Prius). (*disclaimer* - I
am a moderator on this list, which mainly means approving posts of new
members (i.e. weeding out the spam and trolls), banning spammers, and
occasionally helping members with membership/subscription problems.)

Prius-2G focuses on the NHW20 model Prius (2004-current model years in
the US). When the NHW20 was introduced, a new group was formed to
discuss just this new model and its new features... Prius-2G is the
moderated version of that new group (that everyone moved to once the
new group (2004-prius) lost its only owner/moderator and became over-
run with spam).

2007_Prius is a quieter version of Prius-2G. Not as much traffic as
Prius-2G, but stays on-topic more often. (2007_Prius renames itself
each year when the new model year is out...)

Myself, I subscribe to most Yahoo!Groups on a given topic, but just
choose the "No email" option. At least when needed I can go to the
message archives and search around... But for the more-populated
Prius groups, although I read online, I still get the messages via
email so that I can archive them myself for easier searching.
(Although the Yahoo!Groups Message search is now vastly improved, it
still leaves a lot to be desired...)

> > or the more appropriate usenet newsgroup: alt.autos.toyota.prius
>
> My news service doesn't get that one (yet). Thanks, Michelle!

I've had spotty news service for quite a while, so I've resorted to
using http://groups.google.com/ for all of my news feeds. However,
the site changes every so often, and the posting can be a bit clunky.

Google is trying to offer email lists similar to the Yahoo!Groups, and
lists them right next to the usenet newsgroups... but I haven't found
much traffic in the GoogleGroups Prius lists yet.