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Sci.Electronics.Basics -> Why Is DC Power Transmission 10X More Efficient Than AC?
There are 77 messages in this thread.
You are currently looking at messages 40 to 60.
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On Thu, 24 Apr 2008 15:49:20 +1000, "Phil Allison"
<philallison@tpg.com.au> wrote:
>
><spamfree@spam.heaven>
> Bret Cahill = TROLL
>
>
>>>> you came up with.
>>>
>>>Never end sentences with prepositions.
>>
>>
>> Why?
>
>
>** Cos it is a preposterous thing to do.....
Sez who?
jack
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Author: Bret CahillDate: 08:18 24-04-08
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> >Are modern "scientists" really this dense? =EF=BF=BDTen times efficient
i=
sn't
> >920%! =EF=BF=BDWhat you must have just graduated from a "modern" high
sch=
ool?
> >Dig. =EF=BF=BDIf standard transmission is 92% efficient, then that means =
there
> >is 8% of the energy lost. TWICE as efficient would only have 4% of the
> >energy lost or would be 96%.
>
> Your terminology seems pointlessly confusing. =EF=BF=BDPresumably you thin=
k
> a 100% efficient system is 20 times as efficient as another 100%
> system.
>
> The simple answer is that if something is 92% efficient, you can't
> make it 10 times more efficient.
Supposing you wanted a catchy title to your thread?
Bret Cahill
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Author: Judge MentalDate: 19:49 24-04-08
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Author: tadchemDate: 20:03 24-04-08
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On Apr 24, 2:44 am, Benj <bjac...@iwaynet.net> wrote:
> On Apr 23, 8:02 pm, tadchem <tadc...@comcast.net> wrote:
>
> > > Isn't it great when a so-called "scientist" can simply quote
> > > mathematical equations as if they were making sense
>
> > ...and they do make sense, especially when you consider that these
> > equations are definitions and not open to debate.
>
> Since when are equations in science and engineering "not open to
> debate"?
You are welcome to change the *DEFINITIONS* of the terms at your own
pleasure, but be advised that as soon as you do, you no longer have
any common ground for using the term in a discussion with others using
the definition you have chosen to disregard. The logical term for
this process is "equivocation."
> Because simple arithmetic leads to an absurd answer and therefore
> simply does not apply!
...not if simple arithmetic has been misapplied, as in your argument.
> > Can you show me *HOW* 2 x 92% = 96%? I don't think so.
>
> By looking at the data. It's clear that if one system has half as
> much loss as another the one with the greater loss is twice as
> inefficient.
So, you turn the discussion from one of "efficiency" to one of
"loss"
while pretending not to have changed anything. The phrase "it is
clear" is a standard pedagogical cop-out. It usually means "I haven't
bothered to work out the details, but I'm pretty sure this is the way
it is."
> Hence it logically follows from the data that one is
> twice as efficient as the other.
You apparently are not clear on the relationship of "efficiency" to
"loss," either.
> If you want to play English word
> games have at it, but language doesn't have to make sense either,
> ESPECIALLY "muttish" English!
But "science" requires unambiguous communication wherever possible.
To support clear communications, rigorous definitions are established
and all parties agree to adhere to them. These definitions establish
the "playing field" for scientific discussions. If you wish to
discuss a subtly different concept with scientists, you must give your
concept a unique name and definition.
> If you wish to make up equations that
> have no basis in reality
They are not my "equations," but rather mathematical *definitions*
agreed upon by physicists for the study of physics.
> and then claim that somehow it shows you are
> "correct" because the laws of arithmetic are being followed, you can
> say that, but you make no sense in a practical world. Say, how is
> life up there in the Ivory Tower?
I imagine from your perspective a white fire hydrant would seem like
an ivory tower. I work in the real world.
> So the REAL question is what is going on in the system?
This was answered in the Wiki articles which I have previously cited.
It isn't all that complicated.
Electrical power is typically transmitted at 110KV+. At one-thousand
times the voltage of household current, the current of a HV
transmission line is kept low, so the losses are kept low. I could do
the math for you, but by now I'm sure you could not follow it, or if
you could, you would not trust it simply because it is math.
> Trying to
> press mathematical dogma or the rules of English grammar upon any
> situation in no way impresses the power transmission systems. They
> don't listen to either mathematics OR English. If what is going on is
> understood and described, that is sufficient for those people who deal
> with these things. Goofy arguments by you don't make you look any
> smarter.
Excellent words. You should heed them.
> If you want to look smart then tell us what the best efficiency of
> AC<>DC HV converters are these days... (only values under 100% will be
> considered valid)
In the real world, AC to DC 'converters' are called "rectifiers," and
their efficiency depends on their operating voltage, frequency, and
other characteristics of the individual circuit (including the load!).
I have seen a claim (admittedly by 'marketing' types) for >= 97.7%:
http://www.chlorideups.com/Data%20Sheets/40%20kVA.pdf
although elsewhere they state "87% efficiency minimum."
...but here is a peer-reviewed article:
http://ieeexplore.ieee.org/Xplore/login.jsp?url=/iel3/4202/12369/00573386.pdf?temp=x
claiming "92% for a 12 kW rectifier for telecom applications ... for
a 380/480 V three phase AC input utilizing semiconductor devices with
commonly available breakdown voltages ... including predicted and
laboratory measurements of power train efficiency."
Perhaps you will find data in the links on this page informative:
http://category.alldatasheet.com/datasheet-pdf/category/rectifier/efficiency,.html
Tom Davidson
Richmond, VA
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Author: tadchemDate: 20:06 24-04-08
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On Apr 24, 2:37 am, "Y.Porat" <y.y.po...@gmail.com> wrote:
> On Apr 23, 1:17 am, John Larkin
>
>
>
> <jjlar...@highNOTlandTHIStechnologyPART.com> wrote:
> > On Tue, 22 Apr 2008 12:13:06 -0700 (PDT), Bret Cahill
>
> > <BretCah...@aol.com> wrote:
> > >Is there some low frequency radiation or hysterisis loss or what?
>
> > >Bret Cahill
>
> > If you mean long-distance transmission lines, DC can be run at higher
> > average voltages (less corona losses, relatively) and has no skin loss
> > or inductive coupling to the world. I don't know about 10:1.
>
> > DC systems do need inverters and rectifiers on the ends, which have
> > losses.
>
> > John
>
> ----------------
> i dont know what you mean by inverters
"Inverters" convert DC to AC.
> AFAIK
> DC cannot be transform to very high volages-
Not directly. Voltage dividers/multipliers are notoriously
inefficient ("lossy"), but via the sequence "inverter -> transformer -
> rectifier" it can be done.
> OTHOA
> AC can be transformed to huge voltages by trasformers
> yet transformers can work only on AC
> and hight voltage AC is much more efficient than
> any low voltage current
> do i remember correctly ??
>
> ATB
> Y.Porat
> ---------------------------
Tom Davidson
Richmond, VA
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Author: Bret CahillDate: 23:03 24-04-08
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The trifling daffynition hair splitting bean counting nerds here will
never take me alive!
Bret Cahill
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Author: Michael A. TerrellDate: 23:58 24-04-08
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Bret Cahill wrote:
>
> The trifling daffynition hair splitting bean counting nerds here will
> never take me alive!
Don't worry. They don't you, alive. In fact, most people have already
dropped 'all' traffic from the Google Groups portal.
--
http://improve-usenet.org/index.html
Use any search engine other than Google till they stop polluting USENET
with porn and junk commercial SPAM
If you have broadband, your ISP may have a NNTP news server included in
your account: http://www.usenettools.net/ISP.htm
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Author: John LarkinDate: 12:06 25-04-08
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On Wed, 23 Apr 2008 23:37:19 -0700 (PDT), "Y.Porat"
<y.y.porat@gmail.com> wrote:
>On Apr 23, 1:17 am, John Larkin
><jjlar...@highNOTlandTHIStechnologyPART.com> wrote:
>> On Tue, 22 Apr 2008 12:13:06 -0700 (PDT), Bret Cahill
>>
>> <BretCah...@aol.com> wrote:
>> >Is there some low frequency radiation or hysterisis loss or what?
>>
>> >Bret Cahill
>>
>> If you mean long-distance transmission lines, DC can be run at higher
>> average voltages (less corona losses, relatively) and has no skin loss
>> or inductive coupling to the world. I don't know about 10:1.
>>
>> DC systems do need inverters and rectifiers on the ends, which have
>> losses.
>>
>> John
>
>----------------
>i dont know what you mean by inverters
At the source end of DC transmission lines, polyphase
transformer-rectifier circuits convert the AC to high-voltage DC.
At the load end, the DC must be converted back to AC, using
"inverters".
http://en.wikipedia.org/wiki/HVDC#Rectifying_and_inverting_components
>
>AFAIK
>DC cannot be transform to very high volages-
>
>OTHOA
>AC can be transformed to huge voltages by trasformers
>yet transformers can work only on AC
>and hight voltage AC is much more efficient than
>any low voltage current
>do i remember correctly ??
It's easy to google stuff like this, instead of relying on old
memories.
John
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Author: The Ghost In The MachineDate: 10:55 26-04-08
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In sci.physics, Phil Allison
<philallison@tpg.com.au>
wrote
on Wed, 23 Apr 2008 07:32:37 +1000
<6773rgF2n665eU1@mid.individual.net>:
>
> "Dope Bowey"
>
> "JeffM"
>
>>> Bret Cahill wrote:
>>> :10X More Efficient
>>>
>>> Cite your sources for 920% efficiency.
>>
>> Cite where you think he said that. It's not in this thread.
>
>
> ** What is 10 times more efficient than 92 % ??
>
> 920% ?
Presumably, 99.2%. The loss for 92% efficiency
is 8%; reducing that loss by a factor of 10
generates 0.8%.
>
> The OP's question is an absurd troll.
>
> Like you.
I do wonder. We were born about a century too late;
Tesla and Edison produced various papers and/or actions
(including electrocutions!) based on AC (Tesla) and DC
(Edison).
Tesla won, as it turns out.
>
>
>
> ...... Phil
>
>
--
#191, ewill3@earthlink.net
Linux. The choice of a GNU generation.
Windows. The choice of a bunch of people who like very weird behavior on
a regular basis, random crashes, and "extend, embrace, and extinguish".
--
Posted via a free Usenet account from http://www.teranews.com
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Author: Bret CahillDate: 14:42 26-04-08
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> Presumably, 99.2%. =EF=BF=BDThe loss for 92% efficiency
> is 8%; reducing that loss by a factor of 10
> generates 0.8%.
The 8% figure is an average and an arbitrary one at that.
The only reason the 92% efficiency figure appeared is because electric
power just isn't shipped thousands of miles when it is cheaper to
build plants in every town and ship the fuel instead.
The situation changes if a power plant needs to be in a very remote
location like the Sahara. To ship the solar thermal back to N. Europe
would waste 1/2 the energy using HVAC.
This is no thread for bean counters. If it isn't a significant
improvement then you can be sure I'm not interested in it.
> > =EF=BF=BD The OP's question is an absurd troll.
>
> > =EF=BF=BD Like you.
>
> I do wonder. =EF=BF=BDWe were born about a century too late;
> Tesla and Edison produced various papers and/or actions
> (including electrocutions!) based on AC (Tesla) and DC
> (Edison).
>
> Tesla won, as it turns out.
Even HVDC transmission requires AC at the terminals.
Supposedly Edison, not the greatest theortical physicist, thought that
AC wouldn't work or work as well with his incandescent light bulbs.
Supposedly Edison once asked the Serb if he ever ate human flesh but
that might have been a joke.
They hated each other.
Bret Cahill
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Author: AndroclesDate: 15:13 26-04-08
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--
This message is brought to you by Androcles
http://www.androcles01.pwp.blueyonder.co.uk/
"The Ghost In The Machine" <ewill@sirius.tg00suus7038.net> wrote in
message
news:7bsbe5-s07.ln1@sirius.tg00suus7038.net...
| In sci.physics, Phil Allison
| <philallison@tpg.com.au>
| wrote
| on Wed, 23 Apr 2008 07:32:37 +1000
| <6773rgF2n665eU1@mid.individual.net>:
| >
| > "Dope Bowey"
| >
| > "JeffM"
| >
| >>> Bret Cahill wrote:
| >>> :10X More Efficient
| >>>
| >>> Cite your sources for 920% efficiency.
| >>
| >> Cite where you think he said that. It's not in this thread.
| >
| >
| > ** What is 10 times more efficient than 92 % ??
| >
| > 920% ?
|
| Presumably, 99.2%. The loss for 92% efficiency
| is 8%; reducing that loss by a factor of 10
| generates 0.8%.
|
| >
| > The OP's question is an absurd troll.
| >
| > Like you.
|
| I do wonder. We were born about a century too late;
| Tesla and Edison produced various papers and/or actions
| (including electrocutions!) based on AC (Tesla) and DC
| (Edison).
|
| Tesla won, as it turns out.
If you have a high voltage then you can use less current and
you only need a small conductor ... but then you need to
step it down again for safety in domestic applications.
The transformer and AC makes it all possible. Edison's DC
was not a option, there are no DC transformers (or AC
batteries) - besides which a DC generator needs an expensive
commutator.
|
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Author: EeyoreDate: 15:25 26-04-08
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Bret Cahill wrote:
> > Presumably, 99.2%. �The loss for 92% efficiency
> > is 8%; reducing that loss by a factor of 10
> > generates 0.8%.
>
> The 8% figure is an average and an arbitrary one at that.
>
> The only reason the 92% efficiency figure appeared is because electric
> power just isn't shipped thousands of miles when it is cheaper to
> build plants in every town and ship the fuel instead.
>
> The situation changes if a power plant needs to be in a very remote
> location like the Sahara. To ship the solar thermal
Solar thermal isn't electricity, it's heat. I assume you mean PV solar.
> back to N. Europe would waste 1/2 the energy using HVAC.
Why do you think that ? Is there any scientific rationale for it ?
Graham
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Author: Bret CahillDate: 15:41 26-04-08
|
|
> > > Presumably, 99.2%. =EF=BF=BDThe loss for 92% efficiency
> > > is 8%; reducing that loss by a factor of 10
> > > generates 0.8%.
>
> > The 8% figure is an average and an arbitrary one at that.
>
> > The only reason the 92% efficiency figure appeared is because electric
> > power just isn't shipped thousands of miles when it is cheaper to
> > build plants in every town and ship the fuel instead.
>
> > The situation changes if a power plant needs to be in a very remote
> > location like the Sahara. =C2=A0To ship the solar thermal
>
> Solar thermal isn't electricity, it's heat. I assume you mean PV solar.
I think it's a solar trough vapor cycle. Anyway a turbine drives an
alternator in the desert. The voltage is stepped up, rectified,
probably filtered and transmitted to Finland by HVDC where it is
inverted back to ac.
> > back to N. Europe would waste 1/2 the energy using HVAC.
> Why do you think that ? Is there any scientific rationale for it ?
Do the math. If 8% is lost every 200 km using HVAC, then 0.92^8 is
lost going 1600 km.
Bret Cahill
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Author: zzbunker@netscape.netDate: 17:50 26-04-08
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On Apr 22, 3:13=A0pm, Bret Cahill <BretCah...@aol.com> wrote:
> Is there some low frequency radiation or hysterisis loss or what?
It's not. Since what your talking about circulating current losses,
not power losses. Which is why the people who
understand the problem invented digital computers, artifical
intelligence,
fiber optics, lasers, laser disks and robots to solve the problem,
rather than more jerks like science light bulb crtics.
>
> Bret Cahill
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Author: Phil AllisonDate: 18:42 26-04-08
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|
"The Ghost In The Machine TROLL "
>>
>> ** What is 10 times more efficient than 92 % ??
>>
>> 920% ?
>
> Presumably, 99.2%. The loss for 92% efficiency
> is 8%; reducing that loss by a factor of 10
> generates 0.8%.
** ???????????????
Absurd gobbledgook.
........ Phil
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Author: Stephen J. RushDate: 19:38 26-04-08
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On Sat, 26 Apr 2008 11:42:11 -0700, Bret Cahill wrote:
> Supposedly Edison, not the greatest theortical physicist, thought that
> AC wouldn't work or work as well with his incandescent light bulbs.
I'm sure Edison, or one of his employees, tested incandescent lamps on
AC. Edison's real problem with AC was a monumental case of "Not Invented
Here!"
Note that high-voltage DC transmission had to wait for the development of
efficient gas-tube and then solid-state inverters. It just wasn't
practical on a large scale when the only way to make AC from DC was a
motor-generator set.
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Author: Paul E. SchoenDate: 20:42 26-04-08
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"Androcles" <Headmaster@Hogwarts.physics> wrote in message
news:9aLQj.13882$Yy6.9158@newsfe11.ams2...
>
>
> --
> This message is brought to you by Androcles
> http://www.androcles01.pwp.blueyonder.co.uk/
>
> "The Ghost In The Machine" <ewill@sirius.tg00suus7038.net> wrote in
> message
> news:7bsbe5-s07.ln1@sirius.tg00suus7038.net...
> |
> | I do wonder. We were born about a century too late;
> | Tesla and Edison produced various papers and/or actions
> | (including electrocutions!) based on AC (Tesla) and DC
> | (Edison).
> |
> | Tesla won, as it turns out.
>
>
> If you have a high voltage then you can use less current and
> you only need a small conductor ... but then you need to
> step it down again for safety in domestic applications.
> The transformer and AC makes it all possible. Edison's DC
> was not a option, there are no DC transformers (or AC
> batteries) - besides which a DC generator needs an expensive
> commutator.
DC generators with commutators are 19th century technology. Solid state
converters and inverters are essentially DC transformers, but would have
been only wet dreams to Edison and Tesla. It may be that Tesla was the
winner (although not financially and emotionally), but Edison may prove to
be the winner by a few percentage points as solid state technology becomes
cheaper and more efficient.
High voltage is more efficient and practical because insulation is much
cheaper and lighter weight than copper, silver, aluminum, or other good
conductors. And superconductors are not practical for really long
transmission. AC at high voltage will have some losses due to radiation,
inductance, capacitance, and phase shift, as well as resistance, corona and
insulator leakage, which affect both AC and DC. A balanced three phase, 3
wire system transfers 50% more power than a two wire DC system with the
same size wires, and the same voltage to ground, but the AC system will
have inductive and capacitive losses, requires 40% better insulation to
handle peaks, and may have shorter insulator life due to capacitive
current. Also, the AC system is often not well balanced, which puts extra
load on one of the conductors and consequently higher losses.
A DC system can also use the earth (possibly with a smaller buried
conductor) for a return path, which shifts efficiency in its favor as
compared to AC.
But maybe Tesla will prove to be the ultimate winner if his methods of
transmitting power by means of atmospheric and earth resonance ever prove
to be practical and safe.
Paul
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Author: zzbunker@netscape.netDate: 21:22 26-04-08
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|
On Apr 26, 8:42=A0pm, "Paul E. Schoen" <pst...@smart.net> wrote:
> "Androcles" <Headmas...@Hogwarts.physics> wrote in message
>
> news:9aLQj.13882$Yy6.9158@newsfe11.ams2...
>
>
>
>
>
>
>
> > --
> > This message is brought to you by Androcles
> > =A0http://www.androcles01.pwp.blueyonder.co.uk/
>
> > "The Ghost In The Machine" <ew...@sirius.tg00suus7038.net>
wrote in
> > message
> >news:7bsbe5-s07.ln1@sirius.tg00suus7038.net...
> > |
> > | I do wonder. =A0We were born about a century too late;
> > | Tesla and Edison produced various papers and/or actions
> > | (including electrocutions!) based on AC (Tesla) and DC
> > | (Edison).
> > |
> > | Tesla won, as it turns out.
>
> > If you have a high voltage then you can use less current and
> > you only need a small conductor ... but then you need to
> > step it down again for safety in domestic applications.
> > The transformer and AC makes it all possible. Edison's DC
> > was not a option, there are no DC transformers (or AC
> > batteries) - besides which a DC generator needs an expensive
> > commutator.
>
> DC generators with commutators are 19th century technology. Solid state
> converters and inverters are essentially DC transformers, but would have
> been only wet dreams to Edison and Tesla. It may be that Tesla was the
> winner (although not financially and emotionally), but Edison may prove to=
> be the winner by a few percentage points as solid state technology becomes=
> cheaper and more efficient.
>
> High voltage is more efficient and practical because insulation is much
> cheaper and lighter weight than copper, silver, aluminum, or other good
> conductors. And superconductors are not practical for really long
> transmission. AC at high voltage will have some losses due to radiation,
> inductance, capacitance, and phase shift, as well as resistance, corona an=
d
> insulator leakage, which affect both AC and DC. A balanced three phase, 3
> wire system transfers 50% more power than a two wire DC system with the
> same size wires, and the same voltage to ground, but the AC system will
> have inductive and capacitive losses, requires 40% better insulation to
> handle peaks, and may have shorter insulator life due to capacitive
> current. Also, the AC system is often not well balanced, which puts extra
> load on one of the conductors and consequently higher losses.
>
> A DC system can also use the earth (possibly with a smaller buried
> conductor) for a return path, which shifts efficiency in its favor as
> compared to AC.
>
> But maybe Tesla will prove to be the ultimate winner if his methods of
> transmitting power by means of atmospheric and earth resonance ever prove
> to be practical and safe.
Well, in he already is in that sense. Since earth resonance
is just self-fullfilling prophecy, and the only reason it's
even still persued, is because power scientists
are nothing historic asswipes. Which is mostly
why GPS and Cruise Missiles were invented to
solve their idiot Telsa ve Edison problem.
>
> Paul- Hide quoted text -
>
> - Show quoted text -
|
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Author: AndroclesDate: 23:53 26-04-08
|
|
--
This message is brought to you by Androcles
http://www.androcles01.pwp.blueyonder.co.uk/
"Paul E. Schoen" <pstech@smart.net> wrote in message
news:4813cc89$0$19806$ecde5a14@news.coretel.net...
|
| "Androcles" <Headmaster@Hogwarts.physics> wrote in message
| news:9aLQj.13882$Yy6.9158@newsfe11.ams2...
| >
| >
| > --
| > This message is brought to you by Androcles
| > http://www.androcles01.pwp.blueyonder.co.uk/
| >
| > "The Ghost In The Machine" <ewill@sirius.tg00suus7038.net> wrote
in
| > message
| > news:7bsbe5-s07.ln1@sirius.tg00suus7038.net...
| > |
| > | I do wonder. We were born about a century too late;
| > | Tesla and Edison produced various papers and/or actions
| > | (including electrocutions!) based on AC (Tesla) and DC
| > | (Edison).
| > |
| > | Tesla won, as it turns out.
| >
| >
| > If you have a high voltage then you can use less current and
| > you only need a small conductor ... but then you need to
| > step it down again for safety in domestic applications.
| > The transformer and AC makes it all possible. Edison's DC
| > was not a option, there are no DC transformers (or AC
| > batteries) - besides which a DC generator needs an expensive
| > commutator.
|
| DC generators with commutators are 19th century technology.
My goodness... you are right, how could I have missed that?
And Edison lived when?
| Solid state
| converters and inverters are essentially DC transformers, but would have
| been only wet dreams to Edison and Tesla. It may be that Tesla was the
| winner (although not financially and emotionally), but Edison may prove to
| be the winner by a few percentage points as solid state technology becomes
| cheaper and more efficient.
Take down the wires between the pylons and beam the energy across country
using masers, huh?
And for the next wet dream we'll have big mirrors in space focussing
sunlight
on Antarctica to terra-form it, melt that damned ice and show those tree
huggers
some new trees to cuddle up to while we get on with a bit of rape and
plunder
of the mineral wealth there. All the crap about global warming and we've
a whole continent to explore. Too much water? Syphon some off and
leave it on the Moon. All it takes is energy and the Sun has more than
enough.
|
| High voltage is more efficient and practical because insulation is much
| cheaper and lighter weight than copper, silver, aluminum, or other good
| conductors.
Oh, I didn't know HV power lines were insulated...
| And superconductors are not practical for really long
| transmission.
Superconductors are only a wet dream to Edison and Tesla.
| AC at high voltage will have some losses due to radiation,
| inductance, capacitance, and phase shift, as well as resistance, corona
and
| insulator leakage, which affect both AC and DC.
Losses due to phase shift, huh? Power factor correction wasn't
an Edison and Tesla wet dream, was it?
| A balanced three phase, 3
| wire system transfers 50% more power than a two wire DC system with the
| same size wires, and the same voltage to ground, but the AC system will
| have inductive and capacitive losses, requires 40% better insulation to
| handle peaks, and may have shorter insulator life due to capacitive
| current.
Capacitive losses? They get hot, those nasty capacitors...
| Also, the AC system is often not well balanced, which puts extra
| load on one of the conductors and consequently higher losses.
| A DC system can also use the earth (possibly with a smaller buried
| conductor) for a return path, which shifts efficiency in its favor as
| compared to AC.
That sounds like an Edison wet dream to me. Just connect to the steel
frame of the building and the copper pipes from the bathtub. Very useful
for fluorescent lights, I'm sure.
| But maybe Tesla will prove to be the ultimate winner if his methods of
| transmitting power by means of atmospheric and earth resonance ever prove
| to be practical and safe.
|
Got any more wet dreams for us?
There is no "ultimate", we go with what we have... NOW. And the process
will continue to evolve until it blows up in all our faces.
Man, as a species, has survived without technology for 2-3 million years.
What science and technology have done is caused massive overpopulation.
That CANNOT continue. We live in the Golden Age preceding the mighty
crash that will be as dark an age as the demise of the dinosaur, and we are
doing it to ourselves.
|
|
|
|
Author: Paul E. SchoenDate: 00:42 27-04-08
|
|
"Androcles" <Headmaster@Hogwarts.physics> wrote in message
news:mNSQj.150204$cj2.79114@newsfe13.ams2...
>
>
> --
> This message is brought to you by Androcles
> http://www.androcles01.pwp.blueyonder.co.uk/
>
> "Paul E. Schoen" <pstech@smart.net> wrote in message
> news:4813cc89$0$19806$ecde5a14@news.coretel.net...
> |
> | High voltage is more efficient and practical because insulation is much
> | cheaper and lighter weight than copper, silver, aluminum, or other good
> | conductors.
>
>
> Oh, I didn't know HV power lines were insulated...
The lines themselves are not insulated, but they are suspended on insulting
bushings, and of course air itself is an insulator.
>
> | AC at high voltage will have some losses due to radiation,
> | inductance, capacitance, and phase shift, as well as resistance, corona
> | and insulator leakage, which affect both AC and DC.
>
> Losses due to phase shift, huh? Power factor correction wasn't
> an Edison and Tesla wet dream, was it?
>
> | A balanced three phase, 3
> | wire system transfers 50% more power than a two wire DC system with the
> | same size wires, and the same voltage to ground, but the AC system will
> | have inductive and capacitive losses, requires 40% better insulation to
> | handle peaks, and may have shorter insulator life due to capacitive
> | current.
>
> Capacitive losses? They get hot, those nasty capacitors...
Insulators have their own capacitance, and power factor correction
capacitors have some losses from ESR. Also, their cost of procurement and
maintenance need to be factored into the overall efficiency.
>
> | Also, the AC system is often not well balanced, which puts extra
> | load on one of the conductors and consequently higher losses.
> | A DC system can also use the earth (possibly with a smaller buried
> | conductor) for a return path, which shifts efficiency in its favor as
> | compared to AC.
>
> That sounds like an Edison wet dream to me. Just connect to the steel
> frame of the building and the copper pipes from the bathtub. Very useful
> for fluorescent lights, I'm sure.
It's already being done for some transmission lines. But I would not
advocate earth ground return path for distribution.
>
> | But maybe Tesla will prove to be the ultimate winner if his methods of
> | transmitting power by means of atmospheric and earth resonance ever
> prove
> | to be practical and safe.
> |
> Got any more wet dreams for us?
> There is no "ultimate", we go with what we have... NOW. And the process
> will continue to evolve until it blows up in all our faces.
>
> Man, as a species, has survived without technology for 2-3 million years.
> What science and technology have done is caused massive overpopulation.
> That CANNOT continue. We live in the Golden Age preceding the mighty
> crash that will be as dark an age as the demise of the dinosaur, and we
> are
> doing it to ourselves.
Now that is something with which I can at least partially agree. We, the
"enlightened" people of the industrial and technological age, are exerting
unprecedented stresses on our fragile biosphere, and a privileged and
greedy few are reaping temporary financial benefits from human activities
that simply cannot continue on a sustainable basis. The world population
continues to rise, and much of that increase is composed of individuals who
are genetically and behaviorally challenged so that they reperesent more of
a burden than an asset in the grand scheme of things. Dogmatic religions
oppose any sort of limitations or social engineering, yet will not take
direct responsibility for the continued supervision, care, and protective
containment of those who make negative contributions to the advancement of
civilization. And business models and economic metrics require ever
increasing growth as a requirement for success, which encourages
conspicuous consumption, planned obsolescence, depletion of resources, and
waste of energy.
The long-bearded old weirdo in robes has been professing that "The end is
near", and perhaps that is becoming more of a reality that we could see in
our lifetimes.
Paul
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