EV Digest 2683
Topics covered in this issue include:
1) Re: AC controllers
by Peter VanDerWal <[EMAIL PROTECTED]>
2) Evercell
by Peter VanDerWal <[EMAIL PROTECTED]>
3) Re: Emergency Tow Service
by "Chuck Hursch" <[EMAIL PROTECTED]>
4) Re: motor voltage readings
by "Chuck Hursch" <[EMAIL PROTECTED]>
5) Re: RAV4 EV gets 104 mpg
by "Chuck Hursch" <[EMAIL PROTECTED]>
6) Re: RAV4 EV gets 104 mpg
by "Chuck Hursch" <[EMAIL PROTECTED]>
7) RE: Wind turbines in Iowa?
by "Shelton, John D. AW2" <[EMAIL PROTECTED]>
8) Re: Relay Speed Control (was AC Controllers)
by Gordon Niessen <[EMAIL PROTECTED]>
9) RE: Wind turbines in Iowa?
by "Humphrey, Timothy" <[EMAIL PROTECTED]>
10) Re: Emergency Tow Service
by "Mark Hanson" <[EMAIL PROTECTED]>
11) Jack doesn't write the TdS Reports. Mike does.
by M Bianchi <[EMAIL PROTECTED]>
12) Motor, Surprise!
by [EMAIL PROTECTED] (Rhett T. George)
13) Re: That time of the year again...
by "1sclunn" <[EMAIL PROTECTED]>
--- Begin Message ---
Field weakening also reduces the efficiency of the motor and will result
in less range.
Also on series wound motors field weakening can lead to motor arcing
which can damage the motor.
It would be better to use a seperately excited motor, these are designed
to have a different field current to the armature current. Of course
finding EV size SepEx motors is a little tougher than finding series
wound motors, but it is possible.
On Wed, 2003-03-26 at 14:03, Mark Thomasson wrote:
> Thanks for your time analyzing this. Under the circumstances you mention
> below, the best design would be the field weakening approach shown at
> http://www.geocities.com/thomassonmj/motor_circuit.html . By using field
> weakening to control speed though most of the speed range, all the batteries
> will usually be in service. This adds some complexity, but it does give
> continuous, stepless control through most of the speed range. For the low
> tech solution, field current could be controlled with a rheostat without
> much loss in efficiency. I think fusing the circuit will protect it from
> contact welding. Thanks again, Mark T.
>
>
> ----- Original Message -----
> From: "Peter VanDerWal" <[EMAIL PROTECTED]>
> To: "EV" <[EMAIL PROTECTED]>
> Sent: Wednesday, March 26, 2003 12:11 AM
> Subject: Re: AC controllers
>
>
> > I was finally able to get into your site and see your diagram.
> >
> > Regardless of what you think your arrangement will definitely result in
> > an unballanced pack and reduced range.
> > I spend about 1/2 the time driving around at 35 mph (that's the speed
> > limit on most streets in my area). This means that the 12V and 24V
> > sections of your pack would not be used during the constant speed
> > portion of my trips (most of it).
> > The other 1/2 the time I'm driving on the bypass at 55 mph, this uses
> > the 48V section which is also used at 35 mph. This section will get
> > drained long before the rest of the pack and will limit range.
> > You are also subjecting portions of the pack to isolated high current
> > draws which will cause Peukert to further reduce range.
> >
> > It is a clever idea and would be great for low power vehicles if it
> > weren't for the possibility of shorting out the pack if a relay failed
> > by welding shut (not uncommon).
> >
> > On Tue, 2003-03-25 at 15:23, Mark Thomasson wrote:
> > > Thanks, lots of good background here. See my comments below. Mark
> > > Thomasson
> > >
> > >
> > > ----- Original Message -----
> > > From: "Lee Hart" <[EMAIL PROTECTED]>
> > > To: <[EMAIL PROTECTED]>
> > > Sent: Monday, March 24, 2003 10:13 PM
> > > Subject: Re: AC controllers
> > >
> > >
> > > > Lee Hart wrote:
> > > > >> The first problem is that you are not loading the batteries
> equally.
> > > >
> > > > Mark Thomasson replied:
> > > > > In actual city traffic conditions, all the batteries get used almost
> > > > > equally.
> > > >
> > > > That has not been my experience. For many years I drove a ComutaVan,
> > > > which has a 3-step 3-contactor controller (36v with resistor, 36v
> > > > direct, and 72v direct). Its top speed was 55 mph (at 72v), but my
> daily
> > > > commute was on streets with a maximum 40 mph speed limit (which only
> > > > needed 36v). Thus, I only used 72v while accellerating or on hills.
> Most
> > > > of the time was spent cruising at 36v.
> > > >
> > > > With your arrangement, I would have had half the range. I'd arrive at
> > > > work with the lower 36v half of the pack dead, but plenty of charge
> > > > still left in the upper 36v half.
> > >
> > > No, The method I am proposing does not work like this and does not
> suffer
> > > this problem, or at least not in the manner you describe. Referring to
> the
> > > circuit shown at
> http://www.geocities.com/thomassonmj/electric_drive.html ,
> > > suppose that you have a 6v, 12v, 24v, and a 48v battery (represented by
> B1
> > > to B4 in the circuit diagram). Also suppose your top speed is 60 MPH at
> > > full voltage of 90v, and assume that speed is directly proportional to
> > > voltage. For the 15 available voltage steps, the table below shows the
> > > motor voltage, the speed, and the batteries used:
> > >
> > > step 1 6v 4 mph 6v
> > > step 2 12v 8 mph 12v
> > > step 3 18v 12 mph 6v 12v
> > > step 4 24v 16 mph 24v
> > > step 5 30v 20 mph 6v 24v
> > > step 6 36v 24 mph 12v 24v
> > > step 7 42v 28 mph 6v 12v 24v
> > > step 8 48v 32 mph 48v
> > > step 9 54v 36 mph 6v 48v
> > > step10 60v 40 mph 12v 48v
> > > step11 66v 44 mph 6v 12v 48v
> > > step12 72v 48 mph 24v 48v
> > > step13 78v 52 mph 6v 24v 48v
> > > step14 84v 56 mph 12v 24v 48v
> > > step 15 90v 60 mph 6v 12v 24v 48v
> > >
> > > If your usual speed is 40 mph (step10), you would be using batteries12v
> and
> > > 48v. If you're on a hill or need to speed up some, you go to step 11
> > > (batteries 6v, 12v, 48v) or step 12 (batteries 24v, 48v), or maybe
> higher
> > > with other battery combination. If you need to slow down, step 9 uses
> > > batteries 6v and 48v. The point is that the batteries are shuffled in
> and
> > > out of the circuit in a manner that tend to balance their loading during
> the
> > > normal variations of driving speeds. However, if you spend most of your
> > > time below 32 mph, then, with this design, the 48 volt bank will be
> under
> > > utilized. For this and other reasons, the control scheme shown at
> > > http://www.geocities.com/thomassonmj/motor_circuit.html has some
> definite
> > > advantages. Using a shunt field motor, the armature voltage steps
> described
> > > above control speed up to 20 mph. Then, with armature voltage at
> maximum
> > > and all batteries in service, field voltage is weakend to control speed
> up
> > > to 60 mph. Since the field current of shunt motors is typically only 5%
> of
> > > the armature current, controlling this current uses relatively
> inexpensive
> > > components. Also, speed control above 20 MPH is continuous with no
> steps.
> > > With this arrangement, you could think of the armature voltage control
> as a
> > > soft starting system, with the field weaking as the main speed control.
> > > >
> > > > >> Next problem; you still have a lot of contactors. The way they are
> > > > >> arranged, if one fails shorted, it could be disastrous to close the
> > > > >> next one.
> > > >
> > > > > Good point. Each battery bank should be fused.
> > > >
> > > > Note that a fuse is a resistor. It will have more voltage drop than a
> > > > contactor. They are also amazingly expensive for ones that is
> guaranteed
> > > > to work at high DC voltages and currents. You always need at least
> some
> > > > fuses, but want to minimize the number of them.
> > > >
> > > > I think a better solution is not to use SPST contactors; use SPDT
> > > > contactors, built so it is physically impossible to close both
> contacts
> > > > at once even in the event of a welded contact. This is always done in
> > > > commercial contactor controllers.
> > >
> > > Unfortunately, this control scheme does not allow the use of SPDT
> > > contactors. The interlocking you mention could be accomplished with
> > > auxiliary contacts off each contactor tied back into the control circiut
> of
> > > the appropriate interlocked contactor.
> > >
> > > >
> > > > >> This problem has been studied for a very long time by some great
> > > > >> minds. You might want to look at some of their solutions.
> > > >
> > > > > Exactly, that's why I'm asking you guys for input!
> > > >
> > > > Most of the "guys" today have never even seen a contactor controller.
> > > > :-) So, you'll have to study old equipment, books, articles, patents,
> > > > etc. to see how they were done in their "golden age". Nowdays, most of
> > > > the engineers who knew how to design them are dead. So, the ones you
> see
> > > > today are often naive designs by people who lack the knowledge and
> > > > experience to do it right.
> > > >
> > > > Thus, it's easy to find a high-mileage 1920 Detroit Electric with its
> > > > original contactor controller that still works. And, it's easy to find
> a
> > > > low-mileage CitiCar or golf cart with a contactor controller that's
> > > > destroyed.
> > > >
> > > > >> For example, the batteries can be switched in series-parallel
> > > > >> combinations so the load is always divided equally between them.
> > > > >> Twelve 6v batteries can be wired for... 6v, 12v, 18v, 24v, 36v, 72v
> > > >
> > > > > This arrangement would take 33 contacts and gives only 6 steps.
> > > >
> > > > Correct; though that's 11 series/parallel contactors.
> > >
> > > Thanks, good catch.
> > >
> > > >
> > > > > If you are willing to give up on the symmetry, you could get all
> > > > > 12 evenly spaced steps.
> > > >
> > > > If you are using a PM motor, then you need more steps because its
> speed
> > > > is directly proportional to voltage. With a series motor (much more
> > > > common in EVs), you need fewer steps because motor speed is a function
> > > > of both voltage and load. With a series motor, roughly 2:1 voltage
> steps
> > > > turns out to be adequate (6v, 12v, 24v, 48v, 96v, ...)
> > >
> > > The new method gives you smooth 6v increments all the way up.
> > >
> > > >
> > > > > The new method would give 15 steps with 15 6v batteries, but only
> > > > > use 9 relays. Balancing of battery discharge would depend on the
> > > > > natural variability of driving speed.
> > > >
> > > > There was a streetcar controller similar to what you describe.
> However,
> > > > they had a scheme to balance the discharge. All the batteries were in
> > > > series. There were two *big* rotary switches, that could select any
> tap
> > > > from 0v to full pack voltage in 1-battery steps. One wire of each
> rotary
> > > > switch went to each side of the motor.
> > > >
> > > > Start with both rotary switches fully counterclockwise, so both motor
> > > > leads were at the 0 volt tap. To accellerate, turn ONE of the rotary
> > > > switches up. 6v, 12v, 18v, 24v... the farther you advance it, the
> faster
> > > > you go.
> > > >
> > > > But, this would discharge the batteries at the lower end faster,
> because
> > > > they are used less. So, to slow down, leave the first switch where it
> > > > was, and move the SECOND switch up to meet it. This brings the motor
> > > > voltage back down. 24v, 18v, 12v, 6v, and 0v when both switches are on
> > > > the same tap. This discharges the batteries at the higher end of the
> > > > pack faster, thus compensating so all batteries average out to the
> same
> > > > discharge rate.
> > > >
> > > > There was a voltmeter between the two taps, so the operator could see
> > > > the battery voltage. It was a manual process; he looked at the
> voltages
> > > > to see where his weakest battery was, and avoided using that one.
> > > >
> > > > The rotary switches were big slate panels, with coin-sized contacts
> > > > arranged in a circle. The two switch arms were concentric cranks that
> > > > the operator controlled manually.
> > > >
> > > > >> The classic series-parallel switch is a single contactor with 3
> > > > >> contacts:
> > > > >> ______________________
> > > > >> + __|__ K1b |
> > > > >> battery 1 ___ normally closed / K1c
> > > > >> |__________/___________| normally open
> > > > >> | K1a __|__+
> > > > >> / normally open ___ battery 2
> > > > >> |______________________| -
> > > > >>
> > > > >> If you don't need to do regen (carry current in both directions),
> > > > >> then K1a and K1c can be replaced by a big diode. Then series-
> > > > >> parallel switching is done with a single SPST contactor.
> > > >
> > > > > The new method also lets you reduce relay count by using diodes,
> > > > > but diodes always have a forward biase voltage drop (~.7 v for
> > > > > silicon) and therefore energy loss
> > > >
> > > > Contactors have a voltage drop too, especially as they age.
> > >
> > > Mine have .004 ohms each after light usage.
> > >
> > > >
> > > > For low voltage systems you wouldn't use silicon diodes; you'd use
> > > > Schottky diodes (0.5v drop), germanium diodes (0.25v drop), or MOSFETs
> > > > (even less)
> > >
> > > I wonder how the cost of these alternative device compare to silicon?
> > > .
> > > >
> > > > Diodes have other big advantages. They provide a path for the
> inductive
> > > > motor current during switching, which greatly reduces contact arcing
> to
> > > > extend life.
> > >
> > > I planned to use a free wheeling diode, but after seeing very little
> voltage
> > > spiking across the relays on the oscilloscope, I left it out.
> > >
> > > >They also eliminate the timing problem between opening one
> > > > contact and closing another "simultaneously".
> > >
> > > I originally used doides in the circuit for this purpose, but the
> > > multiposition switch I use for speed control has enough "break before
> make"
> > > that they were not needed and I left them out.
> > >
> > > >
> > > > Peukert effects
> > > >
> > > > There's another factor you may not be aware of. The amphour capacity
> of
> > > > a lead-acid battery depends on the load current. The higher the
> current,
> > > > the lower the capacity. It's called the "Peukert effect".
> > > >
> > > > Suppose you have golf cart batteries rated at 6v 225ah (at the 20-hour
> > > > rate). If you load them at 75 amps, they only deliver 144 amphours. If
> > > > you load them at 150 amps, they only deliver 122 amphours.
> > > >
> > > > Now suppose you have twelve of these batteries (a 72v pack). You want
> to
> > > > cruise at a speed that requires 36v at 150 amps. With your controller,
> > > > only half the batteries are supplying this current. Each has to
> provide
> > > > 150 amps, so you can only drive for 122ah / 150a = 49 minutes.
> > >
> > > As discussed above, at half speed I have the 48v bank in service. Speed
> up
> > > a little and I pick up the 6v bank also. Slow down a notch and the 48v
> bank
> > > drops out and the 6v, 12v, and 24v banks come into service. Small
> > > variations in driving speed will balance out the discharge on the banks.
> > >
> > > >
> > > > With a series/parallel controller, the two halves of the pack would be
> > > > in parallel, so each battery delivers half the current or 75 amps. Now
> > > > you can drive for 144ah / 75a = 115 minutes. That's a big
> difference --
> > > > more than 2:1!
> > >
> > > It is definitely a good thing to have all the batteries in service all
> the
> > > time, but this old method gives those big jumps in voltage and uses more
> > > hardware for much fewer voltage steps.
> > > >
> > > > With an electronic PWM controller, it would leave the pack wired for
> > > > 72v. It would draw 72v at 75 amps from the pack, but deliver 36v at
> 150
> > > > amps to the motor. As for the series-parallel case, you could drive
> for
> > > > 115 minutes.
> > > >
> > >
> > > You lost me here. How did the PWM increase 75 A of input current to 150
> A
> > > of output current? Where did all those extra electrons come from?
> > >
> > >
> > > > For your scheme to be viable in any but very small vehicles that run
> at
> > > > full speed almost all the time, I think you really must have some way
> to
> > > > equalize the loading on all the batteries.
> > > > --
> > > > Lee A. Hart Ring the bells that still can ring
> > > > 814 8th Ave. N. Forget your perfect offering
> > > > Sartell, MN 56377 USA There is a crack in everything
> > > > leeahart_at_earthlink.net That's how the light gets in - Leonard
> Cohen
> > > >
> > >
> > --
> > EVDL
> >
>
--
EVDL
--- End Message ---
--- Begin Message ---
Hey Jon, how about giving us an update on the Evercells. Still working
ok?
Do these require batt regs? As I recall you are using a PFC charger.
How picky are these about their charging regime?
I know you've talked about this in the pas but I'd like to get a current
status and besides I think some of the new folks on the list would like
to here more about the Evercells.
So how about detailing what your doing to keep them happy.
Thanks.
--- End Message ---
--- Begin Message ---
I also have the CSAA (AAA - California State Automobile Assoc)
membership that includes the 100-mile tow range. I guess it has
indeed gotten up to $78/yr or something close to that. Was in
the high $60s a few years ago (5-7 years?) when I upgraded from
regular service. I figured that 100 miles from home was as far
as I was going to get with the electric. But haven't needed it
:-), since the EV has never broken down since I got the 100-mile
tow service (the only time the EV left me stranded was during the
first year when I lost the Cursit 1221B controller over the hill
in Mill Valley - AAA charged me something like $15 for that tow
back in 1995). But will probably keep the 100-mile tow service,
since I do get to some pretty remote places with the ICE 4Runner.
Chuck Hursch
Larkspur, CA
NBEAA treasurer and webmaster
www.geocities.com/nbeaa
http://www.austinev.org/evalbum/339.html
----- Original Message -----
From: Bruce EVangel Parmenter <[EMAIL PROTECTED]>
To: <[EMAIL PROTECTED]>
Sent: Wednesday, March 26, 2003 3:21 AM
Subject: Emergency Tow Service
> I have been using AAA membership Emergency Tow Service.
> I am not talking insurance, I am POSTing about Emergency
> Tow Services.
>
> This year's bill will be $78 for a free 100 mile emergency
> service.
>
> I would like to know if other EV drivers have a tow service.
> If so, what company do they use, how much is it per year,
> and what services do they get?
>
> Since no one is hiring, I thought I would see if I could
> $ave on another Emergency Tow Service.
>
> =====
> ' ____
> ~/__|o\__
> '@----- @'---(=
> . http://geocities.com/brucedp/
> . EV List Editor & RE newswires
> . (originator of the above ASCII art)
> =====
>
> __________________________________________________
> Do you Yahoo!?
> Yahoo! Platinum - Watch CBS' NCAA March Madness, live on your
desktop!
> http://platinum.yahoo.com
--- End Message ---
--- Begin Message ---
When I had my Cursit 1221B controller funk going on back towards
the end of 1995 on my 96V VoltsRabbit with 8" ADC motor going up
my steep (~20%) hill to my apt, I wired up voltage-reading leads
to three places to try and find where the problem was occurring:
1) between the battery pack and the main contactor; 2) between
the contactor and the controller; 3) at the motor leads of the
controller. Needless to say, it was rather interesting to watch,
and yes, I was able to avoid hitting anything. I haven't been
real clear as to whether the numbers I'm getting from the digital
voltmeters are all that accurate, considering the PWM going to
the motor and the backfed hash coming back to the batteries. My
Chicago Scientific $20 meter seemed to give reasonable readings
at any of the three locations, while the Radio Shack True RMS $80
meter most definitely was a lost puppy between the contactor and
the controller, if my memory serves me correctly. The problem
that I had was that the car would go up about the first half of
the hill ok, but about halfway up, it would frequently just slow
down to about 5-10mph (one time I accumulated 5 or 6 cars behind
me when this happened - urgh!). This hill is done in 1st gear,
and when things are going good, can be done at about 17-18mph
after a run-up to about 20-22mph at the bottom. 25mph speed
limit, but the way the narrow road twists around the blind corner
(due to the vegetation), I rarely will reach that speed in any
car.
When the car would slow down, the motor voltage would drop from
about 79V (which incidentally was about where the battery voltage
was -> 100% duty cycle) to the 60s. The controller expired after
about a month of this kind of stuff, and the loaner controller
(another 1221B) also started doing the same thing (I figure this
hill puts the 1221 at real close to its amp limit, so I may have
been getting into problems with the Cursit current limit
jiggle-jiggle mechanism). Amperage to go up this hill is about
350A motor and battery, and the motor amperage would hold more or
less the same when the funk would start (the VoltsRabbit starts
out life with a motor amp gauge).
After all this, I eventually installed a Curtis 1231C-8601 500A
controller, and haven't had a bit of trouble, but since I still
had the sensing wiring installed, it was fun to see what the
voltages were under different conditions. Creeping back out of
the carport can be done at about 6V and 50A motor. Going down
the road at 25mph was something like 30V/50A motor (2nd gear).
Freeway at 50mph in 3rd gear is about 60V/135A motor. The car
will do about 70mph maxed out.
Chuck Hursch
Larkspur, CA
NBEAA treasurer and webmaster
www.geocities.com/nbeaa
http://www.austinev.org/evalbum/339.html
----- Original Message -----
From: Jim Coate <[EMAIL PROTECTED]>
To: <[EMAIL PROTECTED]>
Sent: Wednesday, March 26, 2003 4:41 PM
Subject: Re: motor voltage readings
> garry wrote:
> > This is almost frightening when you first see it ...and you
have to
> > ask yourself, if my motor only gets 90 volts why am I
carrying
> > around another 76 volts of battery pack ( that's probably
350 kg )
> > that doesn't appear to be useful at the motor.
>
> I wasn't worried anything was being wasted, in terms of total
power.
> Since the controller acts as a "dc transformer", the relatively
high
> voltage, low current going in shows up at the motor as low
voltage, high
> current. If I lived in a more open area, I could get to a
steady speed
> and the total power in (battery voltage x battery current) and
power at
> the motor (motor voltage x motor current) would be about equal,
as the
> controller is rather efficient. But... I can't play in Boston
traffic
> and watch four meters to verify my voltage readings without
hitting
> something (but officer, I was doing scientific research...)
>
> What I was surprised by was the voltage I was reading versus
the 144
> volts the motor is rated for. This means that probably 99% of
the time
> I'm not really pushing it that much and would be fine with a lo
wer
> voltage battery pack (120 - 132 volts) which means 6-volters
instead of
> 8-volters which could be cheaper to purchase. And the rare
occasions
> where I did use the extra power of the higher voltage I'll live
without
> in exchange for longer battery life.
>
> I had upgraded to a higher voltage pack and to a good
controller at the
> same time. I'm now thinking that a high-current controller to
get the
> beast moving with a 120 volt pack might be an OK combination.
(and save
> the higher voltages for when I have a different battery
chemistry that
> lets me have some real fun...)
>
>
> _________
> Jim Coate
> 1992 Chevy S10
> 1970's Elec-Trak
> http://www.eeevee.com
--- End Message ---
--- Begin Message ---
I would stay away from trying to use $/gal and cents/kwh in
trying to figure the relative efficiencies of vehicles. The
physics angle is the better way to go, using BTUs in a gallon of
gas and BTUs in a kwh.
The Honda Insights with 5-speed manual could get upwards of
70-80mpg, and Plasma Boy indicates he has frequently gone over
90mpg, as have others. This nips pretty close on the heels of
our conversions (and the EV1 for that matter), which I have seen
range anywhere from 2 mi/kwh to 3.5 mi/kwh (we're talking on the
AC side of the charger). Most of the inefficiency of our EVs is
in the batteries and then the charger, or so it seems. At 2
mi/kwh, you're looking at about 72mpg (I like to use
36kwh/gal-of-gas), and 3 mi/kwh is about 108mpg. But even with
an Insight and one of our EVs neck and neck, I would take the EV
for short around-town trips and commuting (since if you fuel it
right, it doesn't have to run on fossil fuels, no cold start-up,
etc), and the Insight for the long trips (since EVs can't deal
with the long trips because of no charging infrastructure).
Another thing is that we are comparing heavy lead-acid EVs with a
light little Insight. Imagine what the efficiency numbers would
be if we could get our EVs down to a comparable weight. Smaller
motors, smaller pack, lighter suspension, etc., etc.
Chuck Hursch
Larkspur, CA
NBEAA treasurer and webmaster
www.geocities.com/nbeaa
http://www.austinev.org/evalbum/339.html
----- Original Message -----
From: Christopher Zach <[EMAIL PROTECTED]>
To: <[EMAIL PROTECTED]>
Sent: Wednesday, March 26, 2003 6:00 AM
Subject: Re: RAV4 EV gets 104 mpg
> I have been reading this MPG thread with interest.
>
> Here in MD, the electricity rate is about 8c per kw/hr.
Actually more like 7
> and a mumble. Then again most of our power comes from Calvert
Cliffs (nuke.
> We so love the nuke) so it's somewhat immune to the price
fixing going on in
> other places.
>
> Question: Is 17c per kw/hr anywhere near "reasonable" as far as
the cost to
> generate/deliver/deal with regs/etc? If so, then Bruce's
calculations point
> out that an Insight/Prius is a more economical and perhaps
eco-friendly car
> than either a RAV E4 or even my Prizm.
>
> Are we going in the right direction?
> CZ
>
> ----- Original Message -----
> From: "Humphrey, Timothy" <[EMAIL PROTECTED]>
> To: <[EMAIL PROTECTED]>
> Sent: Wednesday, March 26, 2003 7:54 AM
> Subject: RE: RAV4 EV gets 104 mpg
>
>
> > It's pretty simple really! (I work for the Gov't. I know how
these guys
> > think :-))
> >
> > If you convert the average BTU's available in gasoline,
121000. (11400 to
> > 128000 is the range I found)
> > and the btu's available in a kw/hr, 3412.
> >
> > Then gasoline has the equivalent of 35.46 kw/hrs. Pretty
close to Tom's 35
> > figure.
> >
> > The Rav4EV needs 30.5kw/100miles. So 35.46 kw/hrs will take
it 116.2
> miles.
> >
> > I used the 2003 Rav4EV mileage figures.
> >
> >
> > Stay Charged!
> >
> > Hump
> >
> >
> >
> > > -----Original Message-----
> > > From: Thomas Shay [mailto:[EMAIL PROTECTED]
> > > Sent: Wednesday, March 26, 2003 2:55 AM
> > > To: [EMAIL PROTECTED]
> > > Subject: Re: RAV4 EV gets 104 mpg
> > >
> > >
> > >
> > > ----- Original Message -----
> > > From: "Bruce EVangel Parmenter" <[EMAIL PROTECTED]>
> > > To: <[EMAIL PROTECTED]>
> > > Sent: Tuesday, March 25, 2003 9:55 PM
> > > Subject: Re: RAV4 EV gets 104 mpg
> > >
> > >
> > > > I was looking at the numbers for the cost of fuel
> > > > and electricity on that page
> > > > http://www.fueleconomy.gov/feg/noframes/16424.shtml
> > > >
> > > > I did not see where they got the mpg figure.
> > > > I would have wanted their equation of where the came
> > > > up with that mpg.
> > >
> > > I looked into this perhaps two years ago. The gummint uses
formulas
> > > for calculating equivalent MPG ratings for electrics and
hybrids to
> > > use in corporate average fuel economy (CAFE) calculations.
These
> > > numbers have no other use so far as I know. As I recall
the formulas
> > > don't consider the difference efficiencies of electric
motors versus
> > > infernal combustion engines.
> > >
> > > If the difference in efficiency is ignored then 1 gallon of
> > > gasoline is
> > > equivalent to about 35 kilowatthours. In the real world 1
gallon of
> > > gasoline will do the work of about 10 kwhr.
> > >
> > > Let's consider the RAV4EV's sister, the ICE RAV4 which
according
> > > to MSN Carpoint gets 25/31 city/highway mpg. Let's guess
29 mpg
> > > for mixed city/highway. Using the 1 equals 10 rule of
thumb yields a
> > > probable miles per kwhr of about 2.9 which is what I'd
expect
> > > for a vehicle
> > > the size and shape of the RAV4. So if one were trying to
> > > estimate electric
> > > consumption and costs the 2.9 figure would be accurate
enough.
> > >
> > > I think the 104 mpg figure was derived by measuring kwhr
per mile
> > > and multiplying that by about 35. 2.9 times 35 is close
to 104.
> > >
> > > Tom Shay
> > >
> >
> >
--- End Message ---
--- Begin Message ---
I see about 33cents/kwh, but that's summertime afternoon peak on
PG&E's TOU metering scheme (E-7). Off-peak is about
8.5cents/kwh, and winter afternoon peak is about 11.5cents/kwh.
Most people are running on the E-1 rate, which is about 11.5
cents/kwh 24/7. I know when I had it, it was 11.9cents/kwh. It
seems I have seen some with E-1 at 10.9cents/kwh. My mother,
however, who moved out here recently, is at 12.8cents/kwh (I
don't know why hers is so high, since she is also E-1). Other
places in the Bay Area I have seen with E-1 at about 13cents/kwh.
Chuck Hursch
Larkspur, CA
NBEAA treasurer and webmaster
www.geocities.com/nbeaa
http://www.austinev.org/evalbum/339.html
----- Original Message -----
From: Peter VanDerWal <[EMAIL PROTECTED]>
To: EV <[EMAIL PROTECTED]>
Sent: Wednesday, March 26, 2003 8:07 AM
Subject: Re: RAV4 EV gets 104 mpg
> > Question: Is 17c per kw/hr anywhere near "reasonable" as far
as the cost to
> > generate/deliver/deal with regs/etc? If so, then Bruce's
calculations point
> > out that an Insight/Prius is a more economical and perhaps
eco-friendly car
> > than either a RAV E4 or even my Prizm.
> >
>
>
> Sure 10 years ago when I lived in Illinois I was paying 13c per
kwh.
> The wierd part is that the coop I was in charged you extra if
you went
> over 600 kwh per month. Everything over 600 kwh was 14.5c per
kwh.
>
> Once again that was 10 years ago so I suspect the price has
gone up
> since.
>
> FWIW I've heard of some prices in California that are over 25c
per kwh.
--- End Message ---
--- Begin Message ---
On another wind-farm note, as you pass through the Straits of Gibralter,
there is a nice little wind farm (about 10 windturbines if I recall
correctly) visible on the Spanish side. Did a lonely Naval
Environmentalist's heart good to see them as we headed for oil country.
John Shelton
-----Original Message-----
From: Lee Hart [mailto:[EMAIL PROTECTED]
Sent: Thursday, March 27, 2003 12:50 AM
To: [EMAIL PROTECTED]
Subject: Re: Wind turbines in Iowa?
> DES MOINES, Iowa (AP) A massive wind farm of 180 to 200 wind
> turbines will be built across 200 acres of northern Iowa farm fields,
> a MidAmerican Energy Holdings Co. official said.
There is a huge wind farm near Willmar MN. I've driven by it several
times, and noticed that almost all of them are idle every single time.
A large windmill was installed on I-94 between Minneapolis and St.
Cloud. I've driven past it dozens of times, and have only seen it in
operation twice.
I don't know what's going on, but they certainly aren't generating much
power.
--
Lee A. Hart Ring the bells that still can ring
814 8th Ave. N. Forget your perfect offering
Sartell, MN 56377 USA There is a crack in everything
leeahart_at_earthlink.net That's how the light gets in - Leonard Cohen
--- End Message ---
--- Begin Message ---
Mark, I do understand the budget process. Though some times I think it
leads us to decisions we pay for later. And I do admire your having the
enthusiasm to try to find a worthy invention. There are many people who
made fortunes on things that many of their friends laughed at.
Good luck
At 09:06 PM 3/26/2003, you wrote:
Gordon, I'm a low budget operation. My Schumacher charger from the local
auto parts store puts out 12 A. I charge the batteries one at a time. The
mini bike only has three batteries. Charging larger battery sets in this
configuration is a problem that I haven't worked through yet. The obvious
solution to me is to have separate charging circuits for the 12, 24, and 48
volt sets.
Yes, most inventions aren't worth the patent filing costs. This may be one
of them. If so, its not my first bonehead idea, and I am sure it won't be
my last! But its fun trying to come up with something useful that's never
been done before. My sincere thanks to everyone on the EV list who has
taken the time to help me out with feedback and comments. Mark T.
--- End Message ---
--- Begin Message ---
It also says they'll pay the farmers $4000.00 per year per turbine. Which
means they will operate in the Red for their entire life cycle. Unless a
high premium is paid by the customers who would elect wind power.
Take my case for instance, I can leave my house on my way to work, and on a
clear day see the turbines on the ridge on the other side of the valley. I
think it's a beautiful sight. It cost me an EXTRA 1.5c per kwh to opt to use
them. I gladly pay it. Crank it up to a nickel and I think it would be a
hard sell.
We're talking about 206 turbines. That's an annual budget of $82667.00 just
for rent for a farm that they say will produce enough power for 85000 homes.
Almost $1000.00 per year per home, ain't gonna sell. Drop one of the zero's
off that rent and I could see it happening.
Stay Charged! (cleanly)
Hump
> -----Original Message-----
> From: Thomas Shay [mailto:[EMAIL PROTECTED]
> Sent: Wednesday, March 26, 2003 11:04 PM
> To: [EMAIL PROTECTED]
> Subject: Re: Wind turbines in Iowa?
>
>
> Beware the flaws in this story.
>
> The first sentence says a wind farm will be built. Later the story
> says regulatory approval is needed and legislation is being sought
> for renewable energy credits. So the wind farm might or might not
> be built.
>
> The story says the project uses no state money. So where will the
> money come from for the renewable energy credits?
>
> The story says today's turbines are 15 times more efficient than those
> made in the 1980s which is utter nonsense!
>
> Tom Shay
>
>
>
>
> ----- Original Message -----
> From: "Rod Hower" <[EMAIL PROTECTED]>
> To: <[EMAIL PROTECTED]>
> Sent: Wednesday, March 26, 2003 6:29 PM
> Subject: Wind turbines in Iowa?
>
>
> > A nice way to charge EV's in the Midwest.
> > I wish we were more progressive in Ohio.
> > It would be nice to charge the TEVan with something
> > besides coal!
> > Dare I say Warren Buffet may be called a terrorist by the
> > Bush adminastrastion, cutting into those oil profits
> > by producing sustainable energy!
> >
> > DES MOINES, Iowa (AP) A massive wind farm of 180 to 200
> wind turbines will
> > be built across 200 acres of northern Iowa farm fields, a
> MidAmerican
> Energy
> > Holdings Co. official said.
> >
> > "We're here to announce the largest wind facility to be
> constructed in the
> > world will be built in Iowa," the company's president Greg Abel said
> during
> > Tuesday's announcement.
> >
> > Billionaire investor Warren Buffett's Omaha, Nebraska-based company,
> > Berkshire Hathaway Inc., owns most of MidAmerican Energy.
> >
> > The company's $323 million wind farm will generate 310 megawatts of
> > electricity, enough to power 85,000 homes, he said.
> >
> > Each wind turbine will produce about 1.5 to 1.65 megawatts of power.
> >
> > Currently, the world's largest wind facility is located in
> Washington and
> > Oregon and produces 300 megawatts of electricity, Abel said.
> >
> > The project will place Iowa third in the nation for wind
> energy production
> > behind California and Texas.
> >
> > Governor Tom Vilsack said the project fits perfectly with
> his vision for
> the
> > state to increase renewable energy sources, create jobs and
> help farmers.
> >
> > Farmers in northwest and north-central Iowa where the
> turbines will be
> > located will be paid about $4,000 a year for each turbine,
> Abel said.
> >
> > The governor has proposed a $50 million fund to promote
> renewable energy
> as
> > part of his economic development plan.
> >
> > "This is the beginning of the new Iowa that we've talked
> about. This is an
> > example of what can happen in our state if we're willing to
> act boldly and
> > act now," he said. "It will enable us to begin the process
> of marketing
> our
> > state as being a forward-thinking state where activities
> are taking place
> > notwithstanding the national economy."
> >
> > The project, which uses no state money, will require
> regulatory approval.
> >
> > MidAmerican is seeking legislation that will ensure that the company
> > receives renewable energy credits for constructing and
> owning its own wind
> > turbines. Current law gives the credits only to companies
> that purchase
> > renewable energy from other sources.
> >
> > Legislative leaders said they expect to begin working on
> the bill this
> week
> > and plan to have it passed and to Vilsack by early May.
> >
> > "You can expect that this will be a high priority issue for
> us," said
> House
> > Speaker Christopher Rants, R-Sioux City.
> >
> > MidAmerican customers will benefit because the company
> negotiated with the
> > state a rate freeze through 2010.
> >
> > Attorney General Tom Miller said his office wanted to make sure that
> Iowans
> > would not pay more for the generation of renewable energy.
> >
> > "It's a wonderful balance, very successfully, of many
> public policies --
> the
> > environment, energy security, consumer rates, economic
> development in our
> > state," Miller said.
> >
> > Abel said new technology -- today's turbines are 15 times
> more efficient
> > than those made in the 1980s -- has made wind energy more
> cost effective.
> >
> > MidAmerican has agreed not to raise electricity costs in
> Iowa and if the
> > company generates higher than expected revenues, a portion
> will be shared
> > with customers, Miller said.
> >
> > MidAmerican Energy Co., based in Des Moines, serves more
> than 673,000
> > electricity customers in Iowa, South Dakota and Illinois.
> >
> > The company's plans call for the first turbines to be
> operational by the
> end
> > of 2004.
> >
> >
>
--- End Message ---
--- Begin Message ---
I have a tow bar for my EV but havn't had to use it since I put it on
several years ago. AAA was $100 per year for 50 miles towing so we dropped
the service in roanoke, VA
----- Original Message -----
From: "David Brandt" <[EMAIL PROTECTED]>
To: "'Bruce EVangel Parmenter'" <[EMAIL PROTECTED]>; <[EMAIL PROTECTED]>
Sent: Wednesday, March 26, 2003 4:11 PM
Subject: RE: Emergency Tow Service
> We also use AAA plus. I think our bill is similar. You also get free
> tourbooks, etc with a membership. I'm pleased with them.
>
> Funny, though, that we use up all our tows for when the ICE's break down,
> and the EV never has...
>
> Actually, my wife did hit a big bump one time, which caused a motor cable
to
> impact and deactivate the main circuit breaker, and she was towed home,
but
> that was really not a malfunction.
>
> -----Original Message-----
> From: Bruce EVangel Parmenter [mailto:[EMAIL PROTECTED]
> Sent: Wednesday, March 26, 2003 5:21 AM
> To: [EMAIL PROTECTED]
> Subject: Emergency Tow Service
>
>
> I have been using AAA membership Emergency Tow Service.
> I am not talking insurance, I am POSTing about Emergency
> Tow Services.
>
> This year's bill will be $78 for a free 100 mile emergency
> service.
>
> I would like to know if other EV drivers have a tow service.
> If so, what company do they use, how much is it per year,
> and what services do they get?
>
> Since no one is hiring, I thought I would see if I could
> $ave on another Emergency Tow Service.
>
> =====
> ' ____
> ~/__|o\__
> '@----- @'---(=
> . http://geocities.com/brucedp/
> . EV List Editor & RE newswires
> . (originator of the above ASCII art)
> =====
>
> __________________________________________________
> Do you Yahoo!?
> Yahoo! Platinum - Watch CBS' NCAA March Madness, live on your desktop!
> http://platinum.yahoo.com
>
>
> IMPORTANT - THIS MESSAGE (INCLUDING ANY ATTACHMENTS) IS INTENDED ONLY FOR
> THE USE OF THE INDIVIDUAL OR ENTITY TO WHICH IT IS ADDRESSED, AND MAY
> CONTAIN INFORMATION THAT IS PRIVILEGED, CONFIDENTIAL AND EXEMPT FROM
> DISCLOSURE UNDER APPLICABLE LAW. IF YOU ARE NOT THE INTENDED RECIPIENT,
YOU
> SHOULD DELETE THIS MESSAGE IMMEDIATELY AND YOU ARE HEREBY NOTIFIED THAT
ANY
> READING, DISSEMINATION, DISTRIBUTION OR COPYING OF THIS MESSAGE, OR THE
> TAKING OF ANY ACTION BASED ON IT IS STRICTLY PROHIBITED. THANK YOU.
>
--- End Message ---
--- Begin Message ---
> Every year Jack does great coverage of this EVent.
> Newbies can expect more if his daily Tour de Sol reports to
> come through on the EV List. Look for them.
Bruce,
I'm sure you were just confused by all that stuff at the end of the Report.
Jack Groh does media publicity for the Tour de Sol. I, Mike Bianchi, write
the Reports.
> Where are the EV charging? etc.
If you look at past reports, there is usually at least one "Tails from the
Charging Trailer" Report. The details don't change much year-to-year.
Too answer some of your questions ...
> Are all EVs charging at the same points in a coordinated effort?
Absolutely.
> Where are the EV charging?
They all are plugged into "The Charging Trailer" which is a collection of
outlets of various sizes and capacities and charging paddles. The teams must
provide an extension cord from their vehicle to the plug. All the plugs have
Ground Fault Interrupters (GFI).
> How are they arranging the charging?
There are set times to "go on the plug" and "come off the plug". The teams are
responsible for monitoring their vehicle's charging. If the breaker trips,
they need to notice that and wake up the keepers of the Charging Trailer to get
it reset. There is a lot of team-work between the keepers and the individual
teams, and often between the teams.
There are digital Watt-hour power meters (like the one on the side of your
house that the electric company uses to measure your usage), one for every
charging vehicle, that are monitored by the Tour de Sol. Those numbers go into
the efficiency calculations.
The Tour de Sol rules, including how the various energy sources are scored, are
all spelled out in a pair of PDF documents available from NESEA.
http://www.nesea.org/transportation/tour/2003RulesEmail.php
> Can someone look and make contact with the Heibao EV team?
Nancy Hazard, Director of the Tour de Sol, tells me that the Heibao team is
planning to come. They are the TBA entry from Whitby, Ontario Canada.
> : Wishing I was there :
Bruce, we know you are here in spirit! The support of the EV listers over the
years has been one of the reasons I keep doing this.
http://www.AutoAuditorium.com/TdS_Reports
--
Mike Bianchi
Foveal Systems
190 Loantaka Way
Madison NJ 07940-1910
+1 973 822-2085 Voice and Fax
[EMAIL PROTECTED]
Create videos of auditorium and classroom presentations without a crew?
Yes!
http://www.AutoAuditorium.com
--- End Message ---
--- Begin Message ---
- Greetings -
In the wake of exchanges regarding back EMF, I put a question on
yesterday's exam in Electric Energy Systems asking what argument
the student would give to someone who wanted to remove back EMF
from a running DC motor. Twenty-seven students gave answers which
were correct in large degree, two being spot on. The twenty-eighth
student did not answer the question. The question had not been
discussed. As the exam was open-book and open-notes, the students
used what they knew and what they quickly researched to formulate
their answers. The answer I'll post is the same as in my posting
to EVDL last Thursday, repeated below.
What is the effect of back EMF? Here is what happens to the voltage.
Supply voltage = motor current x armature (+ brush) resistance +
back EMF
Motor current^2 x resistance = Power lost as heat in the resistance
Where does the shaft power come from? Heating the motor does not yield
any shaft power. The total power equation looks like this.
Power delivered to the armature (powoer in) is
supply voltage x armature current
Power in = power lost to heat + power to shaft
Power to shaft = back EMF x current
good time was had by most all.
Rhett
--- End Message ---
--- Begin Message ---
>
> - Gas mowers are smelly, dirty, noisy, unreliable, and high
> maintenance.
Your telling me
.
>
> The cord. Someone showed me how to deal with the cord. Run the cord up
> one arm, over the neck, down the other arm. That keeps the cord right
> at your hand should you need to move it around and gives you tactile
> feedback about what the cord may be doing. Mow back and forth and
> always turn away from the power source.
I have been thinking of different way to deal with the cord problems one has
with EV's .
1. having a long extension cord when most of the time all you will be using
is 15 feet /////
one way I have gotten around this is by having my cord in two coils then I
can uncoil the short coil with the male end on it and leave the other all
coiled up
2. after many winding and un winding the cord gets twist in it . ////// I
have no solution for this one but think there must be a way to wind the cord
back up and take the twist out .
3 120v outlets don't seem to be able to take 8 hours of 15 amps ////////
don't have a good answer for this , If the charger can controller its self
than running two cords with two plugs has worked or I have put two mail ends
on a cord and pluged them both in , of course the problem is once one is
pluged in you have a live male end .
> They don't cut quite as well and should be sharpened about once
> a year. you can sharpen them yourself in about 15 minutes with no
> special tools, but send email if you are interested in the procedure
> since it doesn't belong on this list.
>
In the summer I sharpened mine every day
Another summer is about to start , I'll be cutting grass from morning to
night ( my record so far is 18 yards in on day) and yes I'll be making some
money but there won't be time for all the EV stuff I'm trying to do.
The nice thing is WHEN my EV bis starts to make some money or even starts to
brake even I'll just let some of my coustermers go. Well I gess I'm
dreaming here . sorry
Steve Clunn.
--- End Message ---
