| Author |
Message |
John Larkin
Guest
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 Posted:
Tue Mar 15, 2005 5:37 am Post subject:
Re: Time to get rid of the resistor. |
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On Sat, 12 Mar 2005 22:08:43 -0800, "Larry Brasfield"
<donotspam_larry_brasfield@hotmail.com> wrote:
| Quote: | Can you imagine a non-dissipative resistor that
could accept thermal noise from another resistor
and convert any fraction of it into work? (This
question is either trick, rhetorical, or a starting
point for an interesting discussion.)
|
I think I could design such a device, depending on what you mean by
"non-dissipative." It might deliver something close to 1e-24 watts if
you allow me to run it in liquid helium.
You can actually, fairly easily, build a black-box device that runs at
room temp but appears as a very cold 50 ohm resistor.
John
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John Larkin
Guest
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| Posted:
Tue Mar 15, 2005 5:40 am Post subject:
Re: Time to get rid of the resistor. |
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On 14 Mar 2005 14:38:44 -0800, "phaeton" <blahbleh666@hotmail.com>
wrote:
| Quote: | Or on a similar note (to the point about transformed energy is only
wasted if you don't want it)...
Some of those very large electrical junctionboxes (look like a huge
heat sink) that you'll find in a lot of industrial parks or on the
edges of shopping centers. You know, the big green ones that buzz
loudly. iirc, they've got a huge step-down transformer in there that
is converting line voltage into something useable by industrial
equpment.
Does the gigantic transformer throw off enough electromagnetic
oscillation to energize the coils of a smaller transformer (about the
size of your fist) if it is placed nearby?
|
Yes.
| Quote: | Could you used this "waste"
to power anything?
|
It's not waste power; you'd be stealing real energy from whoever owns
the shopping center, but not a lot.
John |
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Larry Brasfield
Guest
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| Posted:
Tue Mar 15, 2005 5:45 am Post subject:
Re: Time to get rid of the resistor. |
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"John Larkin" <jjlarkin@highSNIPlandTHIStechPLEASEnology.com>
wrote in message news:rk7c31diu89af80c7ci1p9r3tjgastl6tb@4ax.com...
| Quote: | On Sat, 12 Mar 2005 22:08:43 -0800, "Larry Brasfield"
donotspam_larry_brasfield@hotmail.com> wrote:
Can you imagine a non-dissipative resistor that
could accept thermal noise from another resistor
and convert any fraction of it into work? (This
question is either trick, rhetorical, or a starting
point for an interesting discussion.)
I think I could design such a device, depending on what you mean by
"non-dissipative."
|
That was a little vague, alright. I was just trying to
indicate that not all its input power was converted
to heat, which is redundant in this context.
| Quote: | It might deliver something close to 1e-24 watts if
you allow me to run it in liquid helium.
|
If it can recover some thermal noise from passive
devices that exist same ambient temperature, and
if it delivers any fraction of that power as work
without consuming more power from an outside
source, then you can run it in any medium you
like, and I would like to be an early investor!
Even if it is not that miraculous, I would like to
know how you would do that, in general terms.
| Quote: | You can actually, fairly easily, build a black-box device that runs at
room temp but appears as a very cold 50 ohm resistor.
|
I don't know if it would work in the black box
you have in mind, but a high gain antenna would
do that if aimed right, at least for some range of
frequencies. (We do get to limit that, right?)
--
--Larry Brasfield
email: donotspam_larry_brasfield@hotmail.com
Above views may belong only to me.
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Guest
|
| Posted:
Wed Mar 16, 2005 3:03 am Post subject:
Re: Time to get rid of the resistor. |
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Yes this a serious post. At some point in basic electronics you are
asked to compute the power used by a resistor. For some reason
engineers don't care if the devices they design use energy efficently.
Pick up some batteries off the street that some one has thrown away
they average 1.2 volts. At 1.2 volts an alkaline battery still has
about 40 percent of its energy left. Design a radio to use 4.5 volts
but takes 4 batteries. Have a circuit that uses 3 batteries at a time
while rotating the unused battery at a regular interval. Then when the
voltage of the batteries drops to 1.2 volts each the circuit switches
to using all 4 batteries in series. All the batteries can be run down
to .9 volts each where they have about 10 percent of their energy left.
This idiot circuit could have been made 100 years ago. A modern radio
would test each battery, you could then mix types of batteries in a
radio. A resistor that throws away heat is only one part of an energy
wasting device. Perhaps what I am thinking of is instead of a resistor
you need a current limiting device. |
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Robert Monsen
Guest
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| Posted:
Wed Mar 16, 2005 3:42 am Post subject:
Re: Time to get rid of the resistor. |
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currentresident@veloemail.com wrote:
| Quote: | Yes this a serious post. At some point in basic electronics you are
asked to compute the power used by a resistor. For some reason
engineers don't care if the devices they design use energy efficently.
Pick up some batteries off the street that some one has thrown away
they average 1.2 volts. At 1.2 volts an alkaline battery still has
about 40 percent of its energy left. Design a radio to use 4.5 volts
but takes 4 batteries. Have a circuit that uses 3 batteries at a time
while rotating the unused battery at a regular interval. Then when the
voltage of the batteries drops to 1.2 volts each the circuit switches
to using all 4 batteries in series. All the batteries can be run down
to .9 volts each where they have about 10 percent of their energy left.
This idiot circuit could have been made 100 years ago. A modern radio
would test each battery, you could then mix types of batteries in a
radio. A resistor that throws away heat is only one part of an energy
wasting device. Perhaps what I am thinking of is instead of a resistor
you need a current limiting device.
|
Sadly, a current limiting device wastes the same amount of energy as a
resistor (perhaps more, since it will require some control, which could
take power as well.) The problem is that many times, engineers use the
fact that resistors 'waste' power in their circuits. Dropping a given
amount of current from voltage a to voltage b means that a certain
amount of power must be taken out somehow. Your light idea was a way to
regain some of that power (a very small amount).
However, if you are worried about battery pollution, you should rest
easy knowing that there are circuits that can draw batteries down to
quite low levels. They are proliferating in the form of white light LED
driver circuits. They generally use the magnetic field in inductors to
drive the thing. This is similar to two paddle wheels which are coupled
by a mechanical connection of some kind. If the driving paddle wheel
takes energy from a stream that is dropping 5 meters, it can raise 1/3
of the amount of water up to 15 meters (minus some loss for friction,
energy collection efficiency, etc).
However, considering energy efficiency of resistors when people drive
SUVs to the supermarket and leave their computers on all night is like
rearranging the deck chairs on the titanic as it sinks.
--
Regards,
Robert Monsen
"Your Highness, I have no need of this hypothesis."
- Pierre Laplace (1749-1827), to Napoleon,
on why his works on celestial mechanics make no mention of God. |
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John Larkin
Guest
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| Posted:
Wed Mar 16, 2005 3:50 am Post subject:
Re: Time to get rid of the resistor. |
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On 15 Mar 2005 13:03:07 -0800, currentresident@veloemail.com wrote:
| Quote: | Yes this a serious post. At some point in basic electronics you are
asked to compute the power used by a resistor. For some reason
engineers don't care if the devices they design use energy efficently.
|
It's been demonstrated many times that most consumers will buy cheap
stuff even if they know that a more expensive, energy-efficient gadget
would be cheaper in the long term. So an engineer is often faced with
the simple reality: design it for efficiency, and nobody will buy it.
Go step outside and see all the ugly SUVs on the street. One big SUV
will waste more energy than a million batteries.
Other constraints, like thermal issues and battery life, often make an
engineer choose a more efficient design, like a switching regulator
instead of a linear.
John |
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Larry Brasfield
Guest
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| Posted:
Wed Mar 16, 2005 4:02 am Post subject:
Re: Time to get rid of the resistor. |
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<currentresident@veloemail.com> wrote in message
news:1110920587.265573.188980@o13g2000cwo.googlegroups.com...
| Quote: | Yes this a serious post.
|
Well, I'm glad you're not a troll, then.
| Quote: | At some point in basic electronics you are
asked to compute the power used by a resistor. For some reason
engineers don't care if the devices they design use energy efficently.
|
You have just unjustly slandered a great many
engineers. I am not going to educate you as
to the many ways you are wrong about that,
but I can attest to having seen many engineers
worry about how to converve power rather
than needlessly expending it. I can also see
much evidence of the same in circuits whose
designers I have never met.
| Quote: | Pick up some batteries off the street that some one has thrown away
they average 1.2 volts. At 1.2 volts an alkaline battery still has
about 40 percent of its energy left. Design a radio to use 4.5 volts
but takes 4 batteries. Have a circuit that uses 3 batteries at a time
while rotating the unused battery at a regular interval. Then when the
voltage of the batteries drops to 1.2 volts each the circuit switches
to using all 4 batteries in series. All the batteries can be run down
to .9 volts each where they have about 10 percent of their energy left.
This idiot circuit could have been made 100 years ago.
|
That would have been before the vacuum tube
was invented. Please show me the design of
your system for accomplishing such miracles.
| Quote: | A modern radio
would test each battery, you could then mix types of batteries in a
radio.
|
If this is a good idea, you should develop and
market it, then reap the rewards that accrue
from such a beneficial contribution. Once you
have worked out the implementation details
and done a market study, I would like to see it,
(under a reasonable NDA, of course).
| Quote: | A resistor that throws away heat is only one part of an energy
wasting device.
|
Very true. I have used transistors to waste
energy, even diodes and vacuum tubes. I
wonder if a transmitter antenna counts as an
energy wasting device in your world view.
| Quote: | Perhaps what I am thinking of is instead of a resistor
you need a current limiting device.
|
That would be useful, too. Resistors are often
treasured for their linear E/I relation, so I would
not abandon the energy transmogrifying resistor
too soon. But a current limiter that did not have
that nasty problem of getting hot would be quite
a boon as well. What do you suppose the cost
of these parts will be? Does that matter at all
in your scheme of things?
--
--Larry Brasfield
email: donotspam_larry_brasfield@hotmail.com
Above views may belong only to me. |
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Fred Abse
Guest
|
| Posted:
Thu Mar 17, 2005 1:39 am Post subject:
Re: Time to get rid of the resistor. |
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On Tue, 15 Mar 2005 13:03:07 -0800, currentresident wrote:
| Quote: | For some reason
engineers don't care if the devices they design use energy efficently.
|
Tell that to Jim Lovell and Fred Haise!
--
"Electricity is of two kinds, positive and negative. The difference
is, I presume, that one comes a little more expensive, but is more
durable; the other is a cheaper thing, but the moths get into it."
(Stephen Leacock) |
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Don Kelly
Guest
|
| Posted:
Thu Mar 17, 2005 6:10 am Post subject:
Re: Time to get rid of the resistor. |
|
|
"Larry Brasfield" <donotspam_larry_brasfield@hotmail.com> wrote in message
news:FNQYd.381$_7.871@news.uswest.net...
| Quote: | "Robert Monsen" <rcsurname@comcast.net> wrote in
message news:bsKdnb3q0v1j5K7fRVn-rQ@comcast.com...
currentresident@veloemail.com wrote:
As I understand it the resistor wastes energy by converting it into
heat. Consider this simple circuit a battery connected to a light bulb.
The light bulb shines onto a photocell the photocell charges the
battery. Thus the light bulb functions as a resistor but some of the
energy has been recovered. Now that the problem has been defined
someone who understands the physics better can work on making a
resistor that does not waste power.
Back in physics class, many years ago, I heard about schemes to use
flywheels to store braking energy. This is the same deal. The
idea is that instead of just dissipating the energy into heat, one
somehow couples the brakes into a flywheel, saving some of the
energy.
I believe the Toyota Prius uses a scheme where braking force is used to
charge the battery, but this may be more sales pitch than
reality.
Their technical descriptions indicate this clearly
enough that it would be fraudulent if not true.
Of course, one could assert the the energy
losses make it a gimic, and some performance
numbers would be needed to gainsay that.
--------- |
What is the alternative? Conventional brakes which dissipate all the KE of
the car as heat, or recovering most of the energy by charging the battery?
Not a gimmick. Regenerative braking has been in use for a long time- It is
common in many applications and was used in trolley systems long before
Toyota got into the car business.
Rather than dump all the energy into heat, you can recover a good fraction
of it (motor as generator will be about 80-90% efficient although there
will be other losses in the system and energy recovery at low speeds will
be poor- braking to a complete standstill won't occur. The system is simple
and even ignoring the energy recovery, the savings on brake wear will pay
for it.
--
Don Kelly
dhky@peeshaw.ca
remove the urine to answer
| Quote: |
Just because they say you can't do it doesn't mean it can't be done. You
are never going to win the game (zero energy
dissipation), but you may be able to hedge against loss somewhat. 50
years ago, nobody could have imagined the complexity of
integrated circuits today. Who knows what the next 50 years will bring?
Can you imagine a non-dissipative resistor that
could accept thermal noise from another resistor
and convert any fraction of it into work? (This
question is either trick, rhetorical, or a starting
point for an interesting discussion.)
--
--Larry Brasfield
email: donotspam_larry_brasfield@hotmail.com
Above views may belong only to me.
|
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Don Kelly
Guest
|
| Posted:
Thu Mar 17, 2005 6:10 am Post subject:
Re: Time to get rid of the resistor. |
|
|
"phaeton" <blahbleh666@hotmail.com> wrote in message
news:1110839924.939622.154150@z14g2000cwz.googlegroups.com...
| Quote: | Or on a similar note (to the point about transformed energy is only
wasted if you don't want it)...
Some of those very large electrical junctionboxes (look like a huge
heat sink) that you'll find in a lot of industrial parks or on the
edges of shopping centers. You know, the big green ones that buzz
loudly. iirc, they've got a huge step-down transformer in there that
is converting line voltage into something useable by industrial
equpment.
Does the gigantic transformer throw off enough electromagnetic
oscillation to energize the coils of a smaller transformer (about the
size of your fist) if it is placed nearby? Could you used this "waste"
to power anything? I've always wanted to take a small transformer and
meter up to one and see what i'd get, but with the Patriot Act and
all....
---------- |
No.
The external field of the transformer is pretty damned low. A coil (not
another transformer) *might* in the right configuration inside the tank and
cuddled up to the windings, produce a small open circuit voltage but the
coupling would be so poor that no useful energy could be obtained. Such
transformers are generally 3 phase with even less external field. I have
placed a bismuth spiral field detector directly on the coils of a 3KVA
transformer and got a very low indication-so low that it was useless-
couldn't even tell the difference between loaded and unloaded conditions.
The design of a transformer in the multiple KVA range and higher does
include considerable effort to reduce leakage flux as much as possible.
Consider this, if there was an appreciable field the tank of the transformer
would get bloody hot. Also, as is, there is no energy being lost in leakage
flux so you are not saving energy-why bugger up a good thing?
..
As John says- if you could do this it would be theft of energy.
Easier to steal energy by using a large loop with one side near one phase of
a major power line. And as much of a fools game as the proposal for a number
of reasons and still not an energy conserving process.
--
Don Kelly
dhky@peeshaw.ca
remove the urine to answer
> |
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Larry Brasfield
Guest
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| Posted:
Thu Mar 17, 2005 6:10 am Post subject:
Re: Time to get rid of the resistor. |
|
|
"Don Kelly" <dhky@peeshaw.ca> wrote in message
news:6U7_d.705827$8l.342818@pd7tw1no...
| Quote: | "Larry Brasfield" <donotspam_larry_brasfield@hotmail.com> wrote in message
news:FNQYd.381$_7.871@news.uswest.net...
[Regarding Mr. Monsen's comment:]
I believe the Toyota Prius uses a scheme where braking force is used
to charge the battery, but this may be more sales pitch than reality.
Their technical descriptions indicate this clearly
enough that it would be fraudulent if not true.
Of course, one could assert the the energy
losses make it a gimic, and some performance
numbers would be needed to gainsay that.
What is the alternative? Conventional brakes which dissipate all the KE of
the car as heat, or recovering most of the energy by charging the battery?
Not a gimmick. Regenerative braking has been in use for a long time- It is
common in many applications and was used in trolley systems long before
Toyota got into the car business.
Rather than dump all the energy into heat, you can recover a good fraction
of it (motor as generator will be about 80-90% efficient although there
will be other losses in the system and energy recovery at low speeds will
be poor- braking to a complete standstill won't occur. The system is simple
and even ignoring the energy recovery, the savings on brake wear will pay
for it.
|
Sorry for being too subtle, there. I was actually
casting some basis for doubt of Mr. Monsen's
"may be more sales pitch than reality." If you
read my paragraph closely, you should see that.
(If I had the evidence to gainsay or support that
conjecture, I would have done so. But I lacked
such numbers and so entered that demurral.)
From what I understand of battery performance,
recharge efficiency is one of the major tent poles
in getting high braking recovery efficiency.
I recently had the opportunity to travel with an
engineer's engineer in his hybrid car. As he made
clear, there is much catering to the technophile in
those gadgets, not to mention fantastic milage. I
highly recommend the experience, although I plan
to wait for better battery lifetime and life-cycle
cost statistics to accumulate before I buy one.
--
--Larry Brasfield
email: donotspam_larry_brasfield@hotmail.com
Above views may belong only to me. |
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Roger Johansson
Guest
|
| Posted:
Thu Mar 17, 2005 6:10 am Post subject:
Re: Time to get rid of the resistor. |
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"phaeton" <blahbleh666@hotmail.com> wrote:
| Quote: | Does the gigantic transformer throw off enough electromagnetic
oscillation to energize the coils of a smaller transformer (about the
size of your fist) if it is placed nearby? Could you used this "waste"
to power anything? I've always wanted to take a small transformer and
meter up to one and see what i'd get, but with the Patriot Act and
all....
|
You could try walking by holding a fluoroscent tube at night.
Maybe you will experience something like this
http://www.boxyit.com/r/index.htm
That pictures shows 1300 fluoroscent tubes pushed into the ground under a
power line, photo taken at night. Explanations and discussions here:
http://slashdot.org/articles/04/02/22/1434230.shtml
There are actually laws against stealing electromagnetic power like this,
but a little experiment is not likely to put you in jail.
--
Roger J. |
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Guest
|
| Posted:
Sat Mar 19, 2005 6:04 am Post subject:
Re: Time to get rid of the resistor. |
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|
Thanks everyone I saw some of those LED drivers in the electronics mags
they are two small for me to soider on and still they have the resistor
in series with the LED. |
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Don Kelly
Guest
|
| Posted:
Sat Mar 19, 2005 6:10 am Post subject:
Re: Time to get rid of the resistor. |
|
|
"Larry Brasfield" <donotspam_larry_brasfield@hotmail.com> wrote in message
news:hr8_d.49$fG.1657@news.uswest.net...
| Quote: | "Don Kelly" <dhky@peeshaw.ca> wrote in message
news:6U7_d.705827$8l.342818@pd7tw1no...
"Larry Brasfield" <donotspam_larry_brasfield@hotmail.com> wrote in
message
news:FNQYd.381$_7.871@news.uswest.net...
[Regarding Mr. Monsen's comment:]
I believe the Toyota Prius uses a scheme where braking force is used
to charge the battery, but this may be more sales pitch than reality.
Their technical descriptions indicate this clearly
enough that it would be fraudulent if not true.
Of course, one could assert the the energy
losses make it a gimic, and some performance
numbers would be needed to gainsay that.
What is the alternative? Conventional brakes which dissipate all the KE
of
the car as heat, or recovering most of the energy by charging the
battery?
Not a gimmick. Regenerative braking has been in use for a long time- It
is
common in many applications and was used in trolley systems long before
Toyota got into the car business.
Rather than dump all the energy into heat, you can recover a good
fraction
of it (motor as generator will be about 80-90% efficient although there
will be other losses in the system and energy recovery at low speeds
will
be poor- braking to a complete standstill won't occur. The system is
simple
and even ignoring the energy recovery, the savings on brake wear will
pay
for it.
Sorry for being too subtle, there. I was actually
casting some basis for doubt of Mr. Monsen's
"may be more sales pitch than reality." If you
read my paragraph closely, you should see that.
(If I had the evidence to gainsay or support that
conjecture, I would have done so. But I lacked
such numbers and so entered that demurral.)
From what I understand of battery performance,
recharge efficiency is one of the major tent poles
in getting high braking recovery efficiency.
I recently had the opportunity to travel with an
engineer's engineer in his hybrid car. As he made
clear, there is much catering to the technophile in
those gadgets, not to mention fantastic milage. I
highly recommend the experience, although I plan
to wait for better battery lifetime and life-cycle
cost statistics to accumulate before I buy one.
--
--Larry Brasfield
email: donotspam_larry_brasfield@hotmail.com
Above views may belong only to me.
------ |
Sorry, Larry- I do realise what you were doing and I agree with you in that
the battery and its recharge efficiency is a major problem along with the
energy density and lifetime problems. As for life cycle, there is a cab
driver in Vancouver BC whose older Prius was replaced after over 200,000
trouble free km by a new one (Toyota was going to tear the old one apart to
check all components for wear, etc). He has now retired it to personal use
and bought another for business so it appears that at least one person is
very happy with the hybrid (which, in my mind, considering batteries etc, is
still preferrable to all electric where the problems that you refer to are
more serious.)
--
Don Kelly
dhky@peeshaw.ca
remove the urine to answer |
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