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It's Time To Replace 60 Hz 110V Electricity

S

Steve Spence

Jan 1, 1970
0
high voltage is already used in dc high transmission lines. I'm more
interested in DC in low power applications, like small homes, cabins and
rv's, or high power apps like Electric vehicles. We commonly run higher
voltage packs, and use dc to dc converters to provide 12vdc for
instrumentation or appliances.
 
S

Steve Spence

Jan 1, 1970
0
what transmission line? You think I get 48vdc over a transmission line?
well, maybe the 20 feet from the pv panels to the battery pack ......
 
S

Sam Wormley

Jan 1, 1970
0
Steve said:
high voltage is already used in dc high transmission lines. I'm more
interested in DC in low power applications, like small homes, cabins and
rv's, or high power apps like Electric vehicles. We commonly run higher
voltage packs, and use dc to dc converters to provide 12vdc for
instrumentation or appliances.

You are avoiding the important point--the efficiency of dc-dc conversion.
Tell me how a dc-dc converter works and what its efficiency is compared
to ac-ac conversion. You really should understand the physics involved.

Ohm's Law
http://scienceworld.wolfram.com/physics/OhmsLaw.html

Resistance
http://scienceworld.wolfram.com/physics/Resistance.html
 
A

Anthony Cerrato

Jan 1, 1970
0
"The Ghost In The Machine"
In sci.physics, Mark Thorson
<[email protected]>
wrote
Now that the blackout has shaken the public's faith in
the electric power industry, we have an opportunity
to make much-needed large-scale changes in how
electricity is distributed. [snippage]

I'll admit I like the general idea of a 400 Hz system
but the hum from such a system may get very irritating
(60 Hz hum is irritating enough but at least it's
a low hum). Think of the tone from a 440 Hz tuning
fork to get a general idea; you'd hear that *everywhere*.
(Presumably the Air Force, however, might have some
ideas on how to mitigate that problem. The 60 Hz hum
one hears is primarily from harmonics.)

Besides all the other problems, sounds like a recipe for
mass population deafness--the long-term medical costs to
society might be stupendous! :) Why not just solve all the
problems by building a decent transmission system with
_proper_ protocols?

Ahh, that's not the main problem.
Time to stop being penny-wise and pound
foolish-at least wrt quality of life

It has little to do with "penny-wise and pound foolish" and a hell of
a lot to do with enviro-idiocy"[/QUOTE]

Well I certainly agree with that too. But it's apparently
not the whole story here--this one was a failure in
transmission protocols and infrastructure also, see-
http://www.nytimes.com/2003/08/17/nyregion/17GRID.html?hp
-but ultimately, as I also said, an important part of the
answer is more local power generation is needed to
"regularize" the entire
system with a greater degree of security...and that means
more money spent with _both_ political and voter agreement
on where, when, and how much!

I would agree that, if the over zealous Green movements and
broad antiscience Luddite factions worldwide (including all
the various anti-progressive religious groups attempting to
hold back R&D in several scientific areas, particularly,
bioscience) do not
curtail their foolish excesses, and soon, we are all headed
for harsh times ahead.
out

Ahh, here is the rub.

No matter how smart the transmission system is, it cannot work
miracles. It needs a sufficient reserve capacity behind it. Now,
check the numbers from the last few decades and observe how the excess
generation capacity keeps shrinking. And no, this is not a matter of
being "penny-wise and pound stupid" ("Beeh, beeh, evil corporations
bad, evil corporations bad"), it is a matter of the public strenuosly
objecting to the construction of every power plant and every
transmission line. So, eventually, the public gets what it deserves
("who, me? Me, wrong? Me, the voter" to paraphrase P.J
O'Rourke).

I would be LOL if it weren't so sad and true!
....tonyC
In order to deal with problems properly, you've to diagnose problems
properly, first. Seeking sacrificial lambs may be emotionally
satisfying but it does little to address the issues.

Mati Meron | "When you argue with a fool,
[email protected] | chances are he is doing
just the same"
 
B

Bill Vajk

Jan 1, 1970
0
Steve said:
I don't recall making any claims about safety. 32vdc and 48vdc are no more
dangerous than the 110/220 I deal with daily. Proper precautions are
necessary with both. I'm very experienced with both.

Sorry, you're right. But for a moment there you
looked just like Mark who originated this thread.
 
M

Michael Moroney

Jan 1, 1970
0
This has always been sort of a thought experiment question. Let's
say the Starship Enterprise comes across a civilization with late 1890's
technology and the Anti-Prime Directive is in force (in other words, mess
with them). Their Edison has invented the light bulb, and is looking
at making power plants to market it. Their Westinghouse and Tesla are
also around. We send our best engineers who, drawing from our 100+ years
of experience with power grids and the capability to start from scratch
decide to help them choose parameters such as frequency and voltages.
What would we suggest? Higher AC frequencies produce worse audio hum
and radiate more, lower would produce more light flicker. Voltage?
Is there any reason to not go with 3 phase (use more phases?) (90
degree 2 phase?) Remember they must use late 1890s technology something
that needs to work well into the 21st century equivalent, so no 1MV
DC power lines with semiconducter inverters on each end, at least not
for a century.
 
D

daestrom

Jan 1, 1970
0
Steve Spence said:
so you think that the only reason to use ac instead of dc is the ease in
stepping it up and down? shucks, a dc to dc converter can do that. that's
how we run 12 vdc gadgets in cars from a 144v pack.

there is no difference in efficiency between 110vdc and 110vac. deliver
110vdc to the outlets, and use a dc to dc converter to run 12vdc appliances.

Except that millions of electric motors won't run on DC. I used to have to
maintain DC motors and it takes probably 20 times as many person-hours as
the same hp AC motor.

Three-phase AC motors are easy. DC brushes are a pain.

daestrom
 
D

daestrom

Jan 1, 1970
0
Steve Spence said:
yep, a good site for newbies.

how about a site with a bit more meat for us electronics guys ......

I prefer 48vdc in my house, but I don't need a grid to give it to me.

So should we have two grids? One to deliver 120VDC to residential customers
and one for commercial and industry that need AC?

And does a DC motor driven A/C unit or refrigerator or furnace blower last
as long as its AC equivalent? Or do you perform your own maintenance?

While many loads in a home can work equally well with DC, many uses of
electricity are much more expensive if converted to DC. Who pays? We all
would.

daestrom
 
D

daestrom

Jan 1, 1970
0
Steve Spence said:
I'm not suggesting a change. I just know quite a bit about using dc. We do a
lot of it in EV's, rv's, and off grid homes. a lot of folks have big
misunderstandings about dc. DC is used in some high voltage distribution
already.

Yes, and we used a lot in submarines and diesel-electric surface ships. DC
machinery is a *pain*.

daestrom
 
B

Bill Vajk

Jan 1, 1970
0
Michael said:
This has always been sort of a thought experiment question. Let's
say the Starship Enterprise comes across a civilization with late 1890's
technology and the Anti-Prime Directive is in force (in other words, mess
with them). Their Edison has invented the light bulb, and is looking
at making power plants to market it. Their Westinghouse and Tesla are
also around. We send our best engineers who, drawing from our 100+ years
of experience with power grids and the capability to start from scratch
decide to help them choose parameters such as frequency and voltages.
What would we suggest? Higher AC frequencies produce worse audio hum
and radiate more, lower would produce more light flicker. Voltage?

The only battle I'm aware of is 50 vs. 60 Hz. The US religiously
maintains frequency which Europe, generally, does not. The advent
of the quarz clock movement has removed a great deal of the old
significance of accurately maintaining frequency. Bringing entire
electrical grids into accord with year end fractional second
adjustments to time is, IMO, absurd.
Is there any reason to not go with 3 phase (use more phases?) (90
degree 2 phase?) Remember they must use late 1890s technology something
that needs to work well into the 21st century equivalent, so no 1MV
DC power lines with semiconducter inverters on each end, at least not
for a century.

Conventional three phase power yields significant leverage as
regards infrastructure vs. transmitted power. There is no such
advantage for 90 degree 2 phase, one of the reasons for it not
achieving great popularity. Phases over 3 yield no additional
leverage.
 
J

Jan Panteltje

Jan 1, 1970
0
Now that the blackout has shaken the public's faith in
the electric power industry, we have an opportunity
to make much-needed large-scale changes in how
electricity is distributed.

The system we use now evolved from 19th-century
technology, with patches to adapt it to the rapid
growth which occurred in the 20th century. If we
were creating a new system today, we would never
choose 60 Hz AC. That's almost an ideal frequency
for causing heart fibrillation during an electric shock.
Much better would be the Air Force standard, which
is 115 VAC at 400 Hz. The main reason they chose
400 Hz is not safety, however, but to make transformers
smaller and more efficient. Weight is a major issue
for aircraft.

The Army uses 28 VDC. This is also safer, both because
of the lower voltage and absence of fibrillation hazard.
Edison originally promoted DC electricity in the late
19th century, but it lost out to the AC system because
the transformer technology of the time required AC.
Had the DC system been adopted, the electrical generating
plants would have to be located close to the consumers
of electricity.

We don't have that limitation. With solid-state electronic
switching power converters, we could use high-voltage DC
for distributing power. There would some losses in the switches,
but these are more than compensated by reduced losses in the
transmission lines.

Solar-power enthusiasts often convert their homes to 12 VDC.
That's for compatibility with cheap multicell lead-acid batteries
used to store power.

I propose that now is the time to adopt a new standard.
A DC standard would be best, to reduce the shock hazard.
The voltage should be the lowest practical voltage, both for
the improved safety and perhaps equally important for the
perception of improved safety in the mind of the public.
If you go much below 12V, the wires needed for high-power
appliances become rather thick. If you go much above
28 VDC, the shock hazard from touching exposed live wires
or terminals becomes too high.
Well, I learned (long time ago) that circuit breakers in a DC
circuit when breaking such a circuit, will draw an arc that will NOT
extinguish.
In AC however, the voltage reverses, and is zero at one point, and
the plasma stops existing.
Of cause solid state circuit breakers is the first step.
For very high currents, well (again ;-)) say a 2 kW heater (normal here),
at 24 V will draw 100 Amp.
You cannot use thyristors (even a thyristor has say 0.8 V drop at 100 amps
is 80 Watt loss) in DC, but need to use MOSFETS.
For those not to need a heatsink, they should not dissipate more then half
a Watt or so, so I^2 x R should be < .5
So 100 x 100 x R should be smaller then .5, so Rds on must be < 100 micro
Ohms....
OK.
Then of cause anything hat uses anything else then the net voltage needs a
DC to DC converter.
The efficiency of these will be at about 80 % at best.
No more 60 Hz transformers, less copper and iron weight.
Then of cause all these HF (say 100 kHz or so) voltage converters need
screening....
But it can be done.
400 Hz is irritating in the audio range, buzzzzzzzzzzzzz

Maybe it is not all that simple, electric clocks often use the 60 Hz as
reference.
It WILL create a new market / force people to buy new stuff (that needs not
be better then the old stuff, but compatible with the new system), really
something for the sales people to lobby the politicians ...
Did you know that normal lightbulb's cold resistance is 1/10 of its hot
resistance?
Your DC/DC converter will HAVE to be able to handle any inrush currents...
Now lets look at the normal washing machine motor?
Did you consider cost?
Are you going to replace all electronics appliances in the US?
Now let us look at the generators... You probably, since you quoted Edison,
ALSO know the problems he had getting his 2 DC generators running together
without burning up (when he demonstrated the first street lights).
Many people have been thinking about this stuff many years.
It is all not so simple really.
Once I thought: everybody his own RTG on the balcony, problem solved.
But so much Pu or whatever, someone will drill a hole in one ... dangerous.
Still 3 or so RTGs can power a household for 25 years I think it was.
And no more electricity bills.
Just your monthly payoff at the bank ;-), and given inflation, after 20 years
that will be an insignificant amount.
Take it with you on holiday.
In the electric powered car, or, if you re a professional terrorist in your
sports plane.
Do you not think we should use all that stuff, 60 Hz, very high voltage DC,
RTG etc. in THOSE applications where they fit in best :)?
JP
 
J

Jan Panteltje

Jan 1, 1970
0
Much better would be the Air Force standard, which
is 115 VAC at 400 Hz. The main reason they chose
400 Hz is not safety, however, but to make transformers
smaller and more efficient. Weight is a major issue
for aircraft.

DOA. Skin effect. [Old Man]
For normal switch mode supplies, anything from 3 kHz to
100 kHz is used, skin effect is not such a big issu at
15 kHz.
It will be at MHz.
Since this goes to sci.electronics too, I DID notice some
manufacturer use litze wire in 15 KHz line output stages (using thyristors).
I did design a 15 kHz switch mode, and never calculated for any skin
effect at all, it worked as expected.
Oops and I did not calculate or it in my TV horizontal output
transformers either, oops ... they worked very reliably.
Much better then some others I have seen byte the dust.
So some effect will exists at that frequency...
Too lazy to look up previous postings on this.
Probably get flamed now ;-)

JP
 
S

Scott A Crosby

Jan 1, 1970
0
Tell me how a dc-dc converter works and why that is efficient in high power
situations ... where are the losses in the conversion processes?

The DC is switched to AC via electronics, then transformed, then
rectified. I was trying to find citations on these devices
yesterday. Didn't find one, but I did find a solid state 5kV switch
that can run at 900 amps.

Aparently the equipment exists, but is rather expensive. There are
several 400kV DC intertie systems out now.

The Edison/Tesla debate on AC versus DC is not as universally
applicable as it once was. It has become easier and cheaper to convert
DC to AC without using motor-generator sets.


An instance of this in technology is the modern computer switching
power supply. It goes

AC (60Hz, 110V) --> DC (110V) --> AC (20kHz, 110V)
---(transformer)---> AC(20kHz, 5V) --> DC(5V)

at about 300W. DC(110V) -> DC(5V) is a subset of the conversion.

For links:

http://www.wikipedia.org/wiki/HVDC
http://www.iee.org/Publish/Books/Power/Po029c.cfm?PrintVersion=true

Scott
 
B

Bill Vajk

Jan 1, 1970
0
Scott said:
The Edison/Tesla debate on AC versus DC is not as universally
applicable as it once was. It has become easier and cheaper to convert
DC to AC without using motor-generator sets.

Does DC to AC conversion have a sine wave
output? How do you get DC back to 3 phase?
Then take a look at feeding 3 phase industrial
applications. 2000 amps 480V 3 phase is common.

DC is suitable for really long distance transmission.
It becomes too expensive, on several fronts, for other
uses.
 
"The Ghost In The Machine"
In sci.physics, Mark Thorson
<[email protected]>
wrote
Now that the blackout has shaken the public's faith in
the electric power industry, we have an opportunity
to make much-needed large-scale changes in how
electricity is distributed.
[snippage]

I'll admit I like the general idea of a 400 Hz system
but the hum from such a system may get very irritating
(60 Hz hum is irritating enough but at least it's
a low hum). Think of the tone from a 440 Hz tuning
fork to get a general idea; you'd hear that *everywhere*.
(Presumably the Air Force, however, might have some
ideas on how to mitigate that problem. The 60 Hz hum
one hears is primarily from harmonics.)

Besides all the other problems, sounds like a recipe for
mass population deafness--the long-term medical costs to
society might be stupendous! :) Why not just solve all the
problems by building a decent transmission system with
_proper_ protocols?

Ahh, that's not the main problem.
Time to stop being penny-wise and pound
foolish-at least wrt quality of life

It has little to do with "penny-wise and pound foolish" and a hell of
a lot to do with enviro-idiocy"

It hasn't helped to force the biz into an isolated futures
market either. I'm not saying that this is a physical cause;
I'm saying that it redirects attention.
Ahh, here is the rub.

No, shit.
No matter how smart the transmission system is, it cannot work
miracles. It needs a sufficient reserve capacity behind it. Now,
check the numbers from the last few decades and observe how the excess
generation capacity keeps shrinking. And no, this is not a matter of
being "penny-wise and pound stupid" ("Beeh, beeh, evil corporations
bad, evil corporations bad"), it is a matter of the public strenuosly
objecting to the construction of every power plant and every
transmission line. So, eventually, the public gets what it deserves
("who, me? Me, wrong? Me, the voter" to paraphrase P.J O'Rourke).

Even thought New England power managed to squeak by, around here
the "voter" was promised a ridiculous low cost in order to implement
the split of power distribution and generation. How the hell are
these companies going to do development? They're barely able to
fund maintenance.

Yes, indeed. Then when things will break down, it'll be their fault,
of course:)
Meanwhile, California fiddles while power generation burns.
So what else is new.

Mati Meron | "When you argue with a fool,
[email protected] | chances are he is doing just the same"
 
T

The Ghost In The Machine

Jan 1, 1970
0
In sci.physics, Anthony Cerrato
<[email protected]>
wrote
"The Ghost In The Machine"
In sci.physics, Mark Thorson
<[email protected]>
wrote
Now that the blackout has shaken the public's faith in
the electric power industry, we have an opportunity
to make much-needed large-scale changes in how
electricity is distributed.
[snippage]

I'll admit I like the general idea of a 400 Hz system
but the hum from such a system may get very irritating
(60 Hz hum is irritating enough but at least it's
a low hum). Think of the tone from a 440 Hz tuning
fork to get a general idea; you'd hear that *everywhere*.
(Presumably the Air Force, however, might have some
ideas on how to mitigate that problem. The 60 Hz hum
one hears is primarily from harmonics.)

Besides all the other problems, sounds like a recipe for
mass population deafness--the long-term medical costs to
society might be stupendous! :) Why not just solve all the
problems by building a decent transmission system with
_proper_ protocols? Time to stop being penny-wise and pound
foolish-at least wrt quality of life -- someone recently
said we are the only superpower in the world with a third
world power grid system --let's add a few more backup
generation plants at critical nodes to help the network out
too (all new funding for all this crap is presently tied up
in political squabbles I believe.) We can fix the
system--have Big Blue et al. design the network and
failsafes this time--

All of Big Blue's protocols, good as IBM is, aren't going to
help a system which has no reserve power. Other posters
have already pointed this out; we ship our power over
long distances already (which doesn't help) and the current
blackout was apparently caused by a failure which eventually
led to the unexpected reversal of huge energy flows over key
wires somewhere in the general area (the Ohio line failures
were merely a trigger), presumably causing various breaker
trips and system shutdowns over a matter of less than
a second -- including nuclear power plants, presuambly as
a safety precaution. (I surmise the cadmium damper rods
were shoved in by an emergency solenoid. Of course now
the reactor needs to be nudged carefully back into life,
lest it blow up or melt down. And there has to be load
on the reactor matching its power output. I don't know
how much "give" or buffering there is in a typical
reactor system.)

It's useful to remember how fast electricity flows.
The Earth has an approximate circumference of 40,000 km.
Light travels at 300,000 km/s. These events apparently
transpired in mere tens of milliseconds, despite spreading
out over two time zones (roughly 15 degrees) -- well beyond
man's ability to control directly.

I'll admit I'd like to see some localization of the
problem, possibly by building low-cost solar solutions
on everyone's roof. The problem is, that's not always
possible, especially for office skyscrapers. (I live
in a 2-floor condo, which means I have roof area
covering 4 units. What happens to the other 4?)

I suppose one could attempt to put solar cells on the
windows but one then runs into a variant of the square-cube
problem.

Nor is current electrical solar-cell technology all that
cheap to manufacture. It's basically glass, which needs
to be melted.
in this new age of "the rise of the
machines" have the computers help us instead of hurt us with
protocols designed by smart folks instead of Dumbos--uh,
wasn't all this math and stuff worked out in the 5 decades
of math and physics since the '50s...even without
computers...go back to the game thy etc. lit. or ask that
genius who won the Economics Nobel; he'll work it all out.
And if we have to pay some small price to constantly
maintain a slightly higher power generation capacity so be
it--it will be worth it, particularly when the terrorists
come to call now that they know our vulnerabilities! We have
the technology and a workable current system--we can rebuild
it even better! ...tonyC

The market may work, but we may have to nudge it.
The market ideal, perhaps, would have Premium Power
Companies(tm) guaranteeing 24/7/365 power for those that
pay for it. These power companies would be insured, and
possibly sell insurance. (A little more than "Satisfaction
Guaranteed or your money back" may be needed here; a
fair amount of semiconductor industry can be ruined by a
prolonged outage.)

The rest of us might limp along on the current system,
although there are some issues; suppose, for example,
that the market decides that 12 hours a day (2 on, 2 off)
in a predictable, established pattern is good enough?
Say, one gets power from 7:17 AM to 9:17 AM, then cuts
out until 11:17 AM (not enough to spoil food with good
refrigeration), goes back on, cuts out again at 1:17
PM, etc. This may actually not work very well in light
of consumption patterns (not much goes on while one's
sleeping beyond powering a few electric clocks and keeping
that food cold) but it's a thought, and not a nice one.
(There are also issues on how the power is switched;
presumably this is computer-controlled -- but those computers
better have the usual backups.)

After-market units could be sold warning of an imminent
power outage, in that case; these might be a small
wall-mountable device. "You have 5 minutes left."
"You have 2 minutes left." "You have 30 seconds left."
"5...4...3...2...1...*blink*" (Or one might simply "watch
the clock" as it ticks down towards the next planned
outage.) The units might have rechargable batteries
(not unlike office emergency lighting) and a very tiny
trickle of power might remain in the lines, mostly to
convey information on the power system and when one's power
is expected to come back on. This trickle would be not
unlike TCP/IP protocols over a standard computer network,
which carry a minute amount of power to deliver information.

Of course standard computer networks don't have to worry
about isolating themselves from hundreds of amps of 110
VAC, either. The protocols also have to contend with
step-up and step-down transformers at substations, either
by bypassing them entirely through some sort of isolator
or by amplifying the signal with power from somewhere,
after it goes through the transformer. The information
need not be gigabytes/s so a 60 Hz reference carrier
with modulation may be useful. Of course it would be
a rather slow modulation; standard AM stations have 10
kHz bandwidth at about 600 kHz (at the low frequency end;
the actual band ranges from about 530 to 1700 kHz, IINM),
for example; one might get the ability to transmit within
a 1 Hz bandwidth if one uses similar bandwidth ratios.
It really depends on the Q of the transformers, methinks.

Or one could just buy a good fuel-cell generator.
GE (or Plug Power) apparently is planning one, as an
after-market unit; plug it in to the outside wiring of
one's house and hook it up to a natural gas pipeline, and
you have your very own power plant (and are now of course
beholden to one's natural gas supplier, as opposed to one's
electrical supplier). It's reasonably clean, AIUI, and I
like the idea of shifting the problem nearer the customer.
I"ll admit to some curiosity as to what the polluntants
are, and we do have a natural gas shortage right now, AIUI.
Commercial units may also be available Real Soon Now.

Presumably they're testing the marketing waters; it's
not available yet. Sort of like "Ginger" (aka Segway),
only far less mysteriously marketed.

One could envision a large number of plans -- all of them
more or less based on the premise that reliability is a
commodity, bought and sold in the usual fashion. Natural
gas refrigerators can also be an option. (The compressor
is driven by a motor; who cares what powers that motor?
It might be a dual-power motor but that's not quite as
efficient; the problem is that the electrical elements are
idle during natural gas and the pistons -- presumably it's
a piston engine -- would be idle during electrical power.
Fortunately, it's only a problem during motor startup;
unfortunately, that refrigerator motor starts up a number
of times, in a consumer unit, per day. Some commercial
units already have this option, AIUI.)

Is this the direction we're going? It's an intriguing
one and would foster quite a bit of conservation, but I
can't say I like it.

[.sigsnip]
 
T

The Ghost In The Machine

Jan 1, 1970
0
In sci.physics, [email protected]
<[email protected]>
wrote
"The Ghost In The Machine"
In sci.physics, Mark Thorson
<[email protected]>
wrote
Now that the blackout has shaken the public's faith in
the electric power industry, we have an opportunity
to make much-needed large-scale changes in how
electricity is distributed.
[snippage]

I'll admit I like the general idea of a 400 Hz system
but the hum from such a system may get very irritating
(60 Hz hum is irritating enough but at least it's
a low hum). Think of the tone from a 440 Hz tuning
fork to get a general idea; you'd hear that *everywhere*.
(Presumably the Air Force, however, might have some
ideas on how to mitigate that problem. The 60 Hz hum
one hears is primarily from harmonics.)

Besides all the other problems, sounds like a recipe for
mass population deafness--the long-term medical costs to
society might be stupendous! :) Why not just solve all the
problems by building a decent transmission system with
_proper_ protocols?

Ahh, that's not the main problem.
Time to stop being penny-wise and pound
foolish-at least wrt quality of life

It has little to do with "penny-wise and pound foolish" and a hell of
a lot to do with enviro-idiocy"

It hasn't helped to force the biz into an isolated futures
market either. I'm not saying that this is a physical cause;
I'm saying that it redirects attention.
Ahh, here is the rub.

No, shit.
No matter how smart the transmission system is, it cannot work
miracles. It needs a sufficient reserve capacity behind it. Now,
check the numbers from the last few decades and observe how the excess
generation capacity keeps shrinking. And no, this is not a matter of
being "penny-wise and pound stupid" ("Beeh, beeh, evil corporations
bad, evil corporations bad"), it is a matter of the public strenuosly
objecting to the construction of every power plant and every
transmission line. So, eventually, the public gets what it deserves
("who, me? Me, wrong? Me, the voter" to paraphrase P.J O'Rourke).

Even thought New England power managed to squeak by, around here
the "voter" was promised a ridiculous low cost in order to implement
the split of power distribution and generation. How the hell are
these companies going to do development? They're barely able to
fund maintenance.
In order to deal with problems properly, you've to diagnose problems
properly, first. Seeking sacrificial lambs may be emotionally
satisfying but it does little to address the issues.

Meanwhile, California fiddles while power generation burns.

"Hi, I'm Ahhnold. I have plenty of reserve power in my
huge pectoral muscles."

:)

(Aargh. I'm not sure of Governor Gray Davis' competence
but this recall is ridiculous.)

Fortunately, I think a number of new plants came
online here since 2001 and we've not really had a good
rolling blackout problem since, even during hot weather.
The last notice was a "Restricted Maintenance Operations
notification" (this is apparently the new designation of
the old "No Touch" notifications) on 2003-07-14 at 9:10
PM PDT; presumably they were anticipating hot weather
the next day (I'd have to look at the weather records).
It was subsequently cancelled just shy of 25 hours later.

http://www.caiso.com/awe/noticelog.html

This is a far cry from a Stage 3 Alert, which means power
shutdowns are imminent. Of course we may also be living
on borrowed time (and borrowed power). Enron is alleged
(I don't know if they were convicted or not) to have
manipulated power generation to improve profits.

As the economy comes back, power consumption will, too.
And the economy is coming back. (When the jobs will,
that's another issue.)
 
"The Ghost In The Machine"
In sci.physics, Mark Thorson
<[email protected]>
wrote
Now that the blackout has shaken the public's faith in
the electric power industry, we have an opportunity
to make much-needed large-scale changes in how
electricity is distributed.
[snippage]

I'll admit I like the general idea of a 400 Hz system
but the hum from such a system may get very irritating
(60 Hz hum is irritating enough but at least it's
a low hum). Think of the tone from a 440 Hz tuning
fork to get a general idea; you'd hear that *everywhere*.
(Presumably the Air Force, however, might have some
ideas on how to mitigate that problem. The 60 Hz hum
one hears is primarily from harmonics.)

Besides all the other problems, sounds like a recipe for
mass population deafness--the long-term medical costs to
society might be stupendous! :) Why not just solve all the
problems by building a decent transmission system with
_proper_ protocols?

Ahh, that's not the main problem.
Time to stop being penny-wise and pound
foolish-at least wrt quality of life

It has little to do with "penny-wise and pound foolish" and a hell of
a lot to do with enviro-idiocy"

Well I certainly agree with that too. But it's apparently
not the whole story here--this one was a failure in
transmission protocols and infrastructure also, see-
http://www.nytimes.com/2003/08/17/nyregion/17GRID.html?hp[/QUOTE]

I'm sure there was and I'm sure there are lots of things which can be
improved in the system. But, there is no such thing as perfect
protocols so, bottom line, the robustness of a system depends on
excess capacity and redundancy.
-but ultimately, as I also said, an important part of the
answer is more local power generation is needed to
"regularize" the entire
system with a greater degree of security...and that means
more money spent with _both_ political and voter agreement
on where, when, and how much!

Yep. The thing is, while people never like to spend more money,
they'll still do it once convinced of the need, if that's the only
issue. Once ideological and emotional issues get involved, though,
there is little room for rational compromises.
I would agree that, if the over zealous Green movements and
broad antiscience Luddite factions worldwide (including all
the various anti-progressive religious groups attempting to
hold back R&D in several scientific areas, particularly,
bioscience) do not
curtail their foolish excesses, and soon, we are all headed
for harsh times ahead.
Yes, "back to nature", as many of these movements would like to:)
I'm reminded of a line from one of Terry Pratchett's books. He writes
about this young woman who left home and went to live in a "back to
nature" commune, in a tent somewhere in rural England. So, he writes
"after spending half a year struggling with flies and mosquitos, heat
and cold, mud and slosh, she finally realized why mankind was always
trying to get as far away from nature as possible" (the wording may be
non-exact, I'm quoting from memory, but the content is correct).

Mati Meron | "When you argue with a fool,
[email protected] | chances are he is doing just the same"
 
S

Scott A Crosby

Jan 1, 1970
0
The rest of us might limp along on the current system,
although there are some issues; suppose, for example,
that the market decides that 12 hours a day (2 on, 2 off)
in a predictable, established pattern is good enough?
Say, one gets power from 7:17 AM to 9:17 AM, then cuts
out until 11:17 AM (not enough to spoil food with good
refrigeration), goes back on, cuts out again at 1:17
PM, etc.

Are you CRAZY? Thats like some nightmare from the third world or from
two centuries ago. It'd be like being based on wind, with little
battery life. Unreliable power is far less valuable than reliable power.

There is no way industry, commerce, or residential users could or
would accept this. Lack of reliable power is one of the big things
that hampers the third world from exploiting lost cost of labor. Also,
unreliable power is not necessary at all. Reliable power sufficient to
last for thousands of years has already been mined. Reliable power to
last millions of years is already dissolved in the oceans; we only
need to be smart, like the french, and use it.
This may actually not work very well in light of consumption
patterns (not much goes on while one's sleeping beyond powering a
few electric clocks and keeping that food cold) but it's a thought,

There's A/C. There is a diurnal power cycle, but nighttime demand is
suprisingly high, about 40% of daytime peaks. (See the California ISO
system status page)

Scott
 
D

DarkMatter

Jan 1, 1970
0
high voltage is already used in dc high transmission lines. I'm more
interested in DC in low power applications, like small homes, cabins and
rv's, or high power apps like Electric vehicles. We commonly run higher
voltage packs, and use dc to dc converters to provide 12vdc for
instrumentation or appliances.


Have you ever seen a high capacity flashover?
 
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