What's the capacity factor on THIS nuclear power plant?
Fran
TOKYO : Japan plans to keep its largest nuclear plant closed for at
least a year amid a nationwide scare after it leaked radioactive water
following an earthquake, a newspaper said Thursday.
Tokyo Electric Power Co., which operates the sprawling Kashiwazaki-
Kariwa plant northwest of the Japanese capital, has already asked
other companies to pitch in to meet the metropolis's electricity needs
in peak summer months.
The Nikkei business daily said the government planned to keep the
nuclear plant -- the largest in the world -- closed for at least a
year pending a company review of earthquake safety.
If the study concludes that the facility needs reinforcement, the
plant "could be offline for substantially more than a year," said the
newspaper, which did not specify its sources.
||||
Gosh, I wonder how often I've been told that modern industrial
economies need nukes to maintain baseload, and that the intermittency
of wind power made it unviable.
Fran
Mauried
I dont understand the question.
Whats likely to be left standing when a 6.8 richter scale earthquake
hits a 8 gigawatt wind farm, if there actually was one anywhere.
Vaughn Simon
"Fran" <Fran...@gmail.com> wrote in message
news:1184834723.4...@d30g2000prg.googlegroups.com...
>
> Gosh, I wonder how often I've been told that modern industrial
> economies need nukes to maintain baseload, and that the intermittency
> of wind power made it unviable.
Like Mauried, I guess I don't understand the question. Would you have been
happier if they left the nuke plants operating while they did their evaluation?
The fact is that nuke plants often run at full capacity without interuption for
months at a time. Wind plants lack that characteristic.
Vaughn
>
> Fran
>
Fran
wrote:
> "Fran" <Fran.B...@gmail.com> wrote in message
>
> news:1184834723.4...@d30g2000prg.googlegroups.com...
>
>
>
> > Gosh, I wonder how often I've been told that modern industrial
> > economies need nukes to maintain baseload, and that the intermittency
> > of wind power made it unviable.
>
> Like Mauried, I guess I don't understand the question. Would you have been
> happier if they left the nuke plants operating while they did their evaluation?
Of course not.
> The fact is that nuke plants often run at full capacity without interuption for
> months at a time. Wind plants lack that characteristic.
>
While wind is intermittent, properly sited and spread, the baseload
cover can be quite low. An earthquake isn't going to disable much of
the capacity, and of course the downtime is limited to repair time.
Even allowing a capacity factor of 25%, that is very solid. Even if an
earthquake puts out 10% of the windpower in an area, if the wind
resource happens to be good elsewhere, it might not make a difference.
Not so with nukes. You positively must shut down the plant if
something serious happens. Then you have to track down the problem and
fix it and get an all-clear. Due to the necessarily politically
sensitive nature of the operation, you might have to go well beyond
the precautions that are called for in practice. Indeed, even if there
is no problem in practice, but merely a threat to the plant from, say,
a terrorist, and some wisp of evidence that the plant may be at risk,
down it goes. It would be an obvious thing for a criminal to do.
That's never happening with wind. This plant may never reopen, and
it's certainly going to be out for at least a year. So it's 'capacity
factor' this year will be 0%. I wonder what baseload cover is needed
for that.
Nuclear power, by its nature, concentrates energy supply, and presents
a very inviting target. All the eggs are in one basket, for good or
ill. Wind, wave, solar and other renewables spread the 'eggs' about,
so that if some break the system is not that affected, and not for
long.
I understand that Japan doesn't have a lot of good land-based options,
but this plant was sitting at the juncture of 4 tectonic plates, which
sounds nearly as dumb as siting a motorway and fuel depot at the end
of a short runway at a busy airport. For mine, shoreline wind, wave
energy/OTEC ought to be a much better option for Japan. Natural gas
from biomass is also pretty obvious.
Fran
Mauried
Got any examples of a 8 GW wind farm operating anywhere in the world.
Fran , you need to think about the numbers.
Start by figuring out how many turbines are needed to replace a 8 GW
Baseload power station and then try and figure out where you might
locate them, and most importantly calculate the end cost of the power
that wind farm will produce.
Im no fan of Nukes, but currently in the world there is no renewable
power station operating that can replace a 8GW Nuke plant ,
irrespective of what technology is used.
If the end cost of the wind power isnt similar to the end cost of the
Nuke Power then its not a solution, no matter how safe it may be.
The world doesnt need clean , green and expensive power,especially in
countries like China where they are going for Coal and Nukes, not wind
or solar.
>
>
>
>
>
>
>
>
>
>
>
Fran
First things first:
1. I'm not opposed in principle to nuclear energy. In some settings,
it's certainly the most rational choice, all things considered. I
particularly like the idea of using Thorium as the fertile material,
as I believe the waste management issues are reduced. Having said
that ...
You don't need an 8GW windfarm to operate anywhare. What you might
have instead is 8GW generated from some combination of geographically
dispersed options including geothermal, hydro, wind, NG ( especially
from waste biomass), wave, tidal, solar, and general biomass
combustion. There are now single wind turbines that produce 3.6 MW.
But just to follow your example, an array of those along 200 miles of
coastline where the population density (and thus the demand) was high
would make a valuable contribution. Five every mile (i.e. 1000
turbines) would produce 3.6GW at peak. Even at 30% capacity that's
well above 1GW. Considering the predictability of onshore breezes, and
the fact that you could have these much nearer sea level, where the
air is denser, 30% seems conservative. Fairly obviously, since you're
going to pay for transmission lines anyway, you might as well match it
up with wave or tidal systems and speread the cost across more energy
sources.
> Fran , you need to think about the numbers.
> Start by figuring out how many turbines are needed to replace a 8 GW
> Baseload power station and then try and figure out where you might
> locate them, and most importantly calculate the end cost of the power
> that wind farm will produce.
Probably much less than 4 cents US per KwH.
> Im no fan of Nukes,
They have their place, but the argument about baseload power is a
furphy.
> but currently in the world there is no renewable
> power station operating that can replace a 8GW Nuke plant ,
> irrespective of what technology is used.
That's just it. You DON'T need single installations doing all that
work. In the less developed parts of the world, that would be nuts as
the underlying infrastructure just isn't there to deliver the output
where its needed. But even in the developed world, spreading the work
about makes sense.
> If the end cost of the wind power isnt similar to the end cost of the
> Nuke Power then its not a solution, no matter how safe it may be.
But it can be, and indeed, it could be a lot cheaper in practice, in
the long run.
> The world doesnt need clean , green and expensive power,especially in
> countries like China where they are going for Coal and Nukes, not wind
> or solar.
>
Well actually, they are taking all of the above and one or two other
things. But your framing is wrong. The world (defined as the people in
it) can't afford dirty power, because in the end, they always pay for
it, one way or another. It's just that the costs are hidden or dumped
onto someone like so much bad weather. On paper, it seems cheap
because some other sucker has to suffer the mess or bear the cost of
cleaning it up.
One of the driving forces behind the nuclear industry in Britain was
certainly the opportunity to create the nuclear materials they needed
for the Trident missile program. Without that, and the premium the
British government put on smashing up the coal miners union that had
taken down Heath in 1974, there'd have been little interest. It's this
generation though that is bearing the costs of decommisioning.
Fran
Arnold Walker
You can look at numerous turbine sites over the years and see that.
Whether you are talking California,Hawaii,or Denmark with the large farms .
And abandoned turbines littering the land scape aren't exactly clean power
either.
And as to your price for the power ...why do you think wind power is priced
higher than
conventional power generation. Or for that matter wind and solar needs
government price supports in some fashion.
In spite, of being some ot the oldest forms of power ....both have been
around before electricity came into
general.
For small villages,the biomass power is best in the first round.As the
initial infrastructure is established.
In highly industrialize countries like Japan, land is at a high enorgh
prime, the power plant had best offer
much better return than wind does on a given area.
Given the earthquake factor niether windmills or solar would survive a 6.6
quake ,much less do as well as the reactor in this thread.
>
>
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Vaughn Simon
> Due to the necessarily politically
> sensitive nature of the operation, you might have to go well beyond
> the precautions that are called for in practice. Indeed, even if there
> is no problem in practice, but merely a threat to the plant from, say,
> a terrorist, and some wisp of evidence that the plant may be at risk,
> down it goes. It would be an obvious thing for a criminal to do.
Yes, you are correct in noticing that nuclear power has problems both in
the engineering and a political dimensions, but wind also has its political
problems. I feel that it is safe to predict that wind will have even greater
political problems as time goes on.
>
> That's never happening with wind. This plant may never reopen, and
> it's certainly going to be out for at least a year. So it's 'capacity
> factor' this year will be 0%. I wonder what baseload cover is needed
> for that.
What is the "capacity factor" of a wind plant that has been shut down for
bird migration season?
>
> Nuclear power, by its nature, concentrates energy supply, and presents
> a very inviting target. All the eggs are in one basket, for good or
> ill. Wind, wave, solar and other renewables spread the 'eggs' about,
> so that if some break the system is not that affected, and not for
> long.
Just like my doctor advocates a healthy, diverse, diet for me, I advocate a
healthy mix of power sources. That mix certainly should include renewable
energy, but I don't see a future for civilization without nuclear power.
Vaughn
Fran
wrote:
> "Fran" <Fran.B...@gmail.com> wrote in message
>
> news:1184896441.4...@i13g2000prf.googlegroups.com...
>
> > Due to the necessarily politically
> > sensitive nature of the operation, you might have to go well beyond
> > the precautions that are called for in practice. Indeed, even if there
> > is no problem in practice, but merely a threat to the plant from, say,
> > a terrorist, and some wisp of evidence that the plant may be at risk,
> > down it goes. It would be an obvious thing for a criminal to do.
>
> Yes, you are correct in noticing that nuclear power has problems both in
> the engineering and a political dimensions, but wind also has its political
> problems. I feel that it is safe to predict that wind will have even greater
> political problems as time goes on.
>
Well I see it the other way about. As fossil resources become more
contentious, all non-fossil sources will appear more attractive.
Nuclear energy has its own specific baggage -- the 'mushroom cloud' is
fixed in the popular mind as its chief feature. In a world where the
chief proponents of nuclear energy are the chief advocates of fear
from terror, the pro-nuclear lobby is going to find matters difficult.
Until the right stops encouraging people to fear most of the non-
English speaking world, the idea of using more nuclear energy,
especially outside the G7, won't seem all that appealing to most.
Few people will care if terrorists seize a wind turbine or a solar
collector.
>
>
> > That's never happening with wind. This plant may never reopen, and
> > it's certainly going to be out for at least a year. So it's 'capacity
> > factor' this year will be 0%. I wonder what baseload cover is needed
> > for that.
>
> What is the "capacity factor" of a wind plant that has been shut down for
> bird migration season?
>
>
I'm ready to stand corrected on this but I'm yet to hear of one. And
if there were a prospect of that happening, then the farm is in the
wrong place. Frankly, the morbidity of birds due to wind turbines is
likely to be minimal compared with the impact of coal fired power
plants on birds and other fauna. I'd like to know about the morbidity
of birds near major airports, (and come to that the indirect effects
on bird colonies of the construction of said airports).
>
> > Nuclear power, by its nature, concentrates energy supply, and presents
> > a very inviting target. All the eggs are in one basket, for good or
> > ill. Wind, wave, solar and other renewables spread the 'eggs' about,
> > so that if some break the system is not that affected, and not for
> > long.
>
> Just like my doctor advocates a healthy, diverse, diet for me, I advocate a
> healthy mix of power sources. That mix certainly should include renewable
> energy, but I don't see a future for civilization without nuclear power.
>
Here, we are on much the same page, though I can easily envisage
civilization without nuclear power. That might not be the most
rational choice however. My point would simply be that nuclear power's
value should be assessed on the same basis as any other power source
-- risks, costs, maintainability, and public benefits. When it's a
part of the best solution, I'm for it and when some other package can
do the job better, all things considered, I'm for that.
Fran
Fran
No, I can't. Wind technology is improving each year. Twenty years ago,
they weren't built in the right places or to the right scale.
> Whether you are talking California,Hawaii,or Denmark with the large farms .
> And abandoned turbines littering the land scape aren't exactly clean power
> either.
Much better than abandoned nuclear plants.
> And as to your price for the power ...why do you think wind power is priced
> higher than
> conventional power generation.
Because it doesn't get the kind of price support that nuclear energy
gets?
> Or for that matter wind and solar needs
> government price supports in some fashion.
The Energy Policy Act sets out massive subsidies for nuclear energy.
> In spite, of being some ot the oldest forms of power ....both have been
> around before electricity came into
> general.
> For small villages,the biomass power is best in the first round.As the
> initial infrastructure is established.
> In highly industrialize countries like Japan, land is at a high enorgh
> prime, the power plant had best offer
> much better return than wind does on a given area.
Japan is one of the least stable places on the face of the Earth.
> Given the earthquake factor niether windmills or solar would survive a 6.6
> quake ,much less do as well as the reactor in this thread.
>
But they needn't all be in the same place. You may not have heard, but
Japan is actually an archipeligo -- composed of about 4000 islands.
The turbines in the vicinity of the quake may well have been put out
of action, but the cost of restoring them would have been piffling.
There would have been no panic. They could have been back up within
weeks and maybe less, and all the while, all the others would still be
working.
Fran
daestrom
Don't blow smoke up our skirts. Yes, the air is densest at sea-level, but
what density of air is assumed in the rating of 3.6 MW per wind turbine?
Probably sea-level density don't you think? So 30% isn't 'conservative'.
Problem with onshore/offshore breezes are that they are very diurnal. Each
day at sunrise and sunset they literally stop while the temperature
difference between land and sea reverses. Best figure out some storage to
ride through the daily lulls. So 30% might be more 'optimistic' then
'conservative'.
Not to mention to get up to the 8 GW you would need about eight times the
numbers you've crunched for about 1600 miles of coastline (the 'main' island
of Honshu only has about 591 miles of coastline, undersea cables from
neighboring islands??). That's just to replace *one* nuclear site
(admittedly, their largest).
How much will all that transmission line cost to maintain? Especially if
you plan to size them larger than the wind turbine capacity to accomodate
wave/tidal.
In a country like Japan, it seems wave tide would make a good contribution
if the facilities can be 'hardened' against tsunami.
Let's face it, Japan has some serious challenges to their energy economy.
With no significant fossil fuels and limited land resources they need to
look towards the sea (as they have traditionally done for their food
supply). Something like OTEC might work well if it can be 'hardened'
against the frequent quakes.
daestrom
daestrom
> On Jul 20, 6:24 pm, "Arnold Walker" <arnoldwal...@consolidated.net>
> wrote:
>> "Fran" <Fran.B...@gmail.com> wrote in message
>>
>> news:1184910484.1...@e9g2000prf.googlegroups.com...
>>
>>
>> The hidden cost is also true of wind turbines as well.
>> You can look at numerous turbine sites over the years and see that.
>
> No, I can't. Wind technology is improving each year. Twenty years ago,
> they weren't built in the right places or to the right scale.
>
>> Whether you are talking California,Hawaii,or Denmark with the large farms
>> .
>> And abandoned turbines littering the land scape aren't exactly clean
>> power
>> either.
>
> Much better than abandoned nuclear plants.
Oh puh-lease! Show me a nuclear plant where the owners have just filed
bankruptcy and walked away leaving the plant completely 'abandoned'. Sure,
some nucs have been shutdown. But the plant isn't 'abandoned' for the
government to step in and clean it up or left rusting like several wind
plants have.
>
>> And as to your price for the power ...why do you think wind power is
>> priced
>> higher than
>> conventional power generation.
>
> Because it doesn't get the kind of price support that nuclear energy
> gets?
>
Another red herring. How much funding do nucs get from the feds? The
recent energy act promises to help fund the first few new plants if they
ever get built, but none of that has happened yet. You think the government
is subsidizing nucs somehow?
Wind and PV *do* get significant support from the government in the form of
subsidies, 'green' tax breaks and 'renewable' tax breaks. Yet it is still
expensive. Some of the expense is *probably* because the investors want a
short amortization of the capital. Such facilities don't yet have a very
good track record for operating 40+ years. And investors in general are
more inclined to seek short-term results then what they were willing to
accept 30 years ago.
>> Or for that matter wind and solar needs
>> government price supports in some fashion.
>
> The Energy Policy Act sets out massive subsidies for nuclear energy.
Which have not yet been utilized. But their are 104 nucs already running
today. Don't you see a disconnect there?
>
>> In spite, of being some ot the oldest forms of power ....both have been
>> around before electricity came into
>> general.
>> For small villages,the biomass power is best in the first round.As the
>> initial infrastructure is established.
>> In highly industrialize countries like Japan, land is at a high enorgh
>> prime, the power plant had best offer
>> much better return than wind does on a given area.
>
> Japan is one of the least stable places on the face of the Earth.
>
>
>> Given the earthquake factor niether windmills or solar would survive a
>> 6.6
>> quake ,much less do as well as the reactor in this thread.
>>
>
> But they needn't all be in the same place. You may not have heard, but
> Japan is actually an archipeligo -- composed of about 4000 islands.
> The turbines in the vicinity of the quake may well have been put out
> of action, but the cost of restoring them would have been piffling.
'Piffling'? The cost of restoring them would be on par with the original
cost to build them. There wouldn't be much salvage. The nuc plant however
retains most of its capital value. Even if it needs several million dollars
in repairs, that isn't bad compared to the total investment.
> There would have been no panic. They could have been back up within
> weeks and maybe less, and all the while, all the others would still be
> working.
>
"weeks"?? You seem to think you could just dig the blades up out of the mud
and re-install them? Or maybe you just trot on down to the local BIG_BOX
store and order up some replacements? Seriously, if a tower fell from a
quake, the hub and blades would probably not be salvagable except as scrap
copper and steel. You'd be looking at getting into the manufacturer's sales
queue and whatever lead-time they have.
daestrom
daestrom
"Vaughn Simon" <vaughnsimo...@att.FAKE.net> wrote in message
news:n30oi.177842$Sa4....@bgtnsc05-news.ops.worldnet.att.net...
I think we can all agree to that. Anyone advocating any single energy
source to the exclusion of all else is being simplistic (I'm *not* accusing
Fran of this, but others have tried to argue it in other threads). Wind can
be useful in displacing fossil fuel use, and that's a great thing. But it
has some unique limitations just as nucs and coal have their own set of
limitations.
But the argument that wind is more reliable against natural disasters or
could more easily be restored seems false. Several towers collapsing in a
wind farm is not quickly repaired. And when you start looking at the true
energy density of wind farms and compare that to usage, you start to get an
idea of the magnitude of the problem.
daestrom
Arnold Walker
"daestrom" <daestrom@NO_SPAM_HEREtwcny.rr.com> wrote in message
news:46a0c921$0$16586$4c36...@roadrunner.com...
disasters.
Add in biomass powered generators to the mix...seems that in also any
distaster...it has damaged biomass
in the form of lumber or something.So maybe if you used some of the debri to
recover the community or???
it would be that much less to clean up later.Be it a thrown together home
trashcan gasifier for a home gas generator or
a truck mounted disaster unit brought in by the local /state gov't for
community backuppower and water treatment.
In words throw in some ground zero equipment that does not seem to exist at
the moment. That runs off whatever that wind,earthquake,or
flood "trashed"while the utility and rescue people recover everything.
Don Kelly
No evidence for this.
That's fine- put in these plants and save some fuel elsewhere when the wind
is blowing not too strongly and not too lightly. Over 200 miles of coast,
the wind plants won't be independent as wind conditions will be similar over
this range. That is-if one plant is down due to inadequate wind, then all
will be similarly affected. So, with the widespread wind system there is
still need for online resources to cover this situation- in addition of
normal contingency reserves to cover such things as unplanned shutdowns such
as with the nuclear plant.
There is a balance of resources but it is not as simple a procedure as you
seem to think to come up with a suitable balance. It requires some pretty
solid and hardnosed engineering.
--
Don Kelly dh...@shawcross.ca
remove the X to answer
----------------------------
dave.w...@comcast.net
>
> - Show quoted text -
A few things. One, Fran argues for a dispersed wind-farm scenerio. Yet
it is percisely the ability to cluster them (no one I know of to be
fair is proposing a "8 GW wind farm anywhere) in 200, 400 and even 600
MW farms is WHY they can be cheap to build. It centralizing DC-to-AC
invertors, it creates shorter distances between turbine/generators
thus reducing costs of infractructure, etc. This is the ONLY a viable
way to build them. Of course even these kind of farms are spread out
of dozens of square miles sometimes.
Secondly, she states that some can "provide 3.6 MWs a peak". No, they
are billed as 3.6 MWs *whenever* the wind blows, which may or may not
be at peak and, of course, usually isn't given a daily capacity factor
of say, 20 to 45% a day spread out over a 24 hour period.
Wind will never repalce on damand power unless two things happens:
1. One overbuilds to achieve 100% capacity, maning you have to build
12 MWs of wind for every 3 MW you want (remember I stated "replaces on
demand power") or
2. You slighly over build and there exists, NOW (meaning in the near
future) true scalable storage capacity with tranformer like
effiencie--2 to 5% net loss only.
The plant now may NOT be down for at least a year in Japan. Full
assesement will come out in a week or so and from this the regulartory
agencies will in conjuction with civil and nuclear engineers, figure
out what it will take to do the repairs (minor it seems for now) and
any buttressing they need. The plant WILL be back on line. Only
reactor damage I think would take these puppies out for good.
The plants did what they were supposed to do. Very little radiation
was released.
This proves that private industry should not running nuclear power
plants, at least not in Japan where the operating companies have a
history of lying to the public and the gov't. They should re-
nationalize the electric industry there for good.
Having said that, even in Japan, with corporate lying, their nuclear
industry still has a good record and they have not stopped working on
the other 3 plants they are building. More importantly, the Chinese
and Indians, the largest builders of plants, haven't even batted an
eyelash and continue building, because they HAVE TO, their dozens of
NPPs.
David
dave.w...@comcast.net
wrote:
> "Vaughn Simon" <vaughnsimonHATESS...@att.FAKE.net> wrote in message
>
> news:n30oi.177842$Sa4....@bgtnsc05-news.ops.worldnet.att.net...
>
>
>
>
>
>
>
> > "Fran" <Fran.B...@gmail.com> wrote in message
>
> - Show quoted text -
Fran is the best and most unemotional anti-nuke advocate on the
internet that I can see. I read both Wasseman and Nader's totally
emotionally and ill-informed (see: Helen Caldicott) spews on
counterpunch.com. Fran should be writing for them, not these guys.
Nader is better than Wasserman. I really think you guys ought to read
him (former leade of the Clamshell Alliance). Unbelievable. "near
breach of the reactor" "near meltdown" "makes more CO2 than it saves",
etc etc. Totally a fool.
David
nicks...@ece.villanova.edu
>... it is percisely the ability to cluster them
>... It centralizing DC-to-AC invertors, it creates shorter distances
>... thus reducing costs of infractructure, etc.
>... This is the ONLY a viable way to build them.
>... Of course even these kind of farms are spread out of dozens...
>Wind will never repalce on damand power unless two things happens:
>1. One overbuilds to achieve 100% capacity, maning you have to build...
>2. You slighly over build and there exists, NOW (meaning in the near
>future) true scalable storage capacity with tranformer like effiencie--
>The plant now may NOT be down for at least a year in Japan. Full
>assesement will come out in a week or so and from this the regulartory
>agencies will in conjuction with civil and nuclear engineers...
Perhaps he learned English from George W. Bush? :-)
Nick
Anthony Matonak
...
> A few things. One, Fran argues for a dispersed wind-farm scenerio. Yet
> it is percisely the ability to cluster them (no one I know of to be
> fair is proposing a "8 GW wind farm anywhere) in 200, 400 and even 600
> MW farms is WHY they can be cheap to build. It centralizing DC-to-AC
> invertors, it creates shorter distances between turbine/generators
> thus reducing costs of infractructure, etc. This is the ONLY a viable
> way to build them. Of course even these kind of farms are spread out
> of dozens of square miles sometimes.
To the best of my knowledge, utility sized wind turbines don't use
DC-to-AC inverters and, even if they did, they would be located on
the turbines themselves and not "centralizing".
The only two big requirements for utility grade wind turbines are
wind resources and access to power lines.
Anthony
dave.w...@comcast.net
<anthony...@nothing.like.socal.rr.com> wrote:
If the generators produce DC then they need to convert it to 60Hz AC.
Even if it's AC, the frequency has to be regulated by solid state
voltage regulators, which, maybe included in the turbine package, I
don't know. But, the issue of spread out turbines is the point I was
responding to Fran about...access to the grid is critical, and, can be
costly (as it is for any energy source and has to be included).
David
Vaughn Simon
<dave.w...@comcast.net> wrote in message
news:1185135605.9...@d55g2000hsg.googlegroups.com...
> If the generators produce DC then they need to convert it to 60Hz AC.
> Even if it's AC, the frequency has to be regulated by solid state
> voltage regulators, which, maybe included in the turbine package, I
> don't know. But, the issue of spread out turbines is the point I was
> responding to Fran about...access to the grid is critical, and, can be
> costly (as it is for any energy source and has to be included).
Strange as it may seem, those fancy controls and inverters you logically
expect to see are only optional on a wind turbine. Actually many wind
generators use a generator that is little more than a simple squirel cage motor
that tends to lock itself onto the grid frequency. If the blade tries to push
the generator too fast, then the generator tends to bog the blade down, pulling
it back into sync. If these generators were not connected to the grid, they
would not work.
This guy explains it a bit differently: "Most manufacturers of wind
turbines use traditional electricity generators for AC at grid frequency (50 Hz
or 60 Hz), and these generators are usually wired directly to the grid. The
generators only produce electricity at the grid frequency if rotating at an
exactly constant (synchronous generator) speed, or nearly constant (induction
generator) speed, of say 1500 rpm. Matching the rotor to this requires a
gearbox; for instance, with a generator speed of 1500 rpm, and a rotor shaft at
30 rpm, a gearbox with a ratio of 50:1 is required. If the gearbox has only one
speed ratio, then the designer has to design for one wind speed (usually, the
'most probable wind speed'). If there are two speed ratios, it is possible to
reduce the rotor speed to match low wind speeds, and then use the increased
gearbox ratio for the 50 Hz or 60 Hz electricity generation. When the wind is at
speeds other than the design (rated) wind speed, generation can still occur, but
the efficiency of energy capture is less. At much larger wind speeds, this
inefficiency becomes a benefit, as the generator is then less likely to be
overloaded." From:
http://jxj.base10.ws/magsandj/rew/2003_03/wind_turbines.html
Vaughn
dave.w...@comcast.net
wrote:
> <dave.walt...@comcast.net> wrote in message
Actually that's sort of amazing they are truly "paralleled to the
system" like my unit is (a steam unit). Most wind turbines are *not*
paralled in this way, being DC which allows variable wind strength.
The whole Danish grid was destabilized last year for a day because
they couldn't control the voltage with the power fluxuating the way it
can with wind. Still, the AC idea is intersting. But, running at an
*exact* frequency is impossible as I see it, it is not enough to have
one or two settings since speed varies constantly, and if you are
paralled, meaning the generator will turn at *exactly* system speed
(1800/3600 RPMs in the US) then you would end up with a tremendous
amount of "motoring" (where the system turns the generator like a
motor instead of pushing VARS out of the generator) and create huge
burn up of the windings generator.
I'll have to read the paper, it does sound interesting.
David
Fran
Thanks for the bouquet, but strictly speaking, it's not correct to
describe me as an "anti-nuke advocate". As on all important questions,
my attitude to energy generation reflects utility. This applies as
much to the energy sources I'm most bullish on as those I'm least
enthusiastic about.
What I am is a silver bullet sceptic. The pollyannaish posturing of
some in the nuclear energy lobby is intellectually offensive. In some
settings, nuclear energy is going to be well short of the best option
on a whole range of grounds. In others of course, utility would demand
it. There's little doubting that the high capital cost of nuclear
energy implies a massive slice of the non-coal market, and to that
extent, some of the rubbishing of alternatives by the nuclear
bandwagon people reflects their fear that this nibbling away of this
sector could make nukes unviable. Needless to say, umbrage is taken on
the other side and that can skew debate away from sober analysis.
My own predisposition, all else being roughly equal, is for localised
power generation, and for solutions that leave local communities in a
good position to control this important resource. I favour solutions
that promote equity, and that can deliver benefits now when they are
needed rather than 15 years down the track. As someone who favours the
liberation of working humanity, I'm bothered by energy options that
involve that part of humanity bearing the burden of harm if the things
goes awry. Since, in practice, nuclear energy plants, and the
materials they use require the highest level of protection, the choice
of nuclear energy necessarily comes with all sorts of "national
security" pack-ins, which, by implication, anyone accepting it has to
endorse. If you will the end, you must will the means, plainly.
Nuclear energy, by definition, can rarely meet these standards. At the
very least, a transparent debate needs to take place which weighs
these considerations against the benefits of the technology. I don't
say it's impossible to meet these standards, but they should be met
before someone advocates it.
> I read both Wasseman and Nader's totally
> emotionally and ill-informed (see: Helen Caldicott) spews on
> counterpunch.com. Fran should be writing for them, not these guys.
They wouldn't like what I had to say.
Fran
Fran
I'm not sure. I was referring to those mooted for Nantucket. I suppose
the standard might be air at sea level, but that would be odd because
most wind turbines are mounted at some height to take advantage of
swifter moving air.
> Problem with onshore/offshore breezes are that they are very diurnal. Each
> day at sunrise and sunset they literally stop while the temperature
> difference between land and sea reverses. Best figure out some storage to
> ride through the daily lulls. So 30% might be more 'optimistic' then
> 'conservative'.
>
In which case the problem is simplified. If you know when the winds
will be good and where they are coming from you can take account of
that in your planning of other outputs.
> Not to mention to get up to the 8 GW you would need about eight times the
> numbers you've crunched for about 1600 miles of coastline (the 'main' island
> of Honshu only has about 591 miles of coastline, undersea cables from
> neighboring islands??). That's just to replace *one* nuclear site
> (admittedly, their largest).
>
True. I see no problem with that. Those extra 7000 turbines are going
to be a lot cheaper than the first 1000. And of course, there are
going to be times when collectively they produce a lot more than 8GW.
> How much will all that transmission line cost to maintain?
It depends. Presumably, the nuclear plant sends energy to these
islands already via transmission lines. They cost what they cost.
> Especially if
> you plan to size them larger than the wind turbine capacity to accomodate
> wave/tidal.
>
Well aren't they currently taking the output of the nuclear plant?
> In a country like Japan, it seems wave tide would make a good contribution
> if the facilities can be 'hardened' against tsunami.
>
True
> Let's face it, Japan has some serious challenges to their energy economy.
> With no significant fossil fuels and limited land resources they need to
> look towards the sea (as they have traditionally done for their food
> supply). Something like OTEC might work well if it can be 'hardened'
> against the frequent quakes.
>
True, it might.
Fran
Mauried
Heres some numbers to throw around
Japans total electricity consumption in 2005 (from Cia Factbook) was
946 billion Kwh.
That requires a generating capacity of a mere 108 GW running 24/7.
Japans growth rate is currently running at 3.3% but has been as high
as 5% in 2006.
Japan has a geographic area of 377000 sq km and 150 million people.
If you try and run Japan on Windfarms where will the people go.
There simply aint enuf room.
You have to look at the numbers and the energy needs.
Fran
wrote:
> "Fran" <Fran.B...@gmail.com> wrote in message
>
> news:1184929156....@e16g2000pri.googlegroups.com...
>
>
>
>
>
> > On Jul 20, 6:24 pm, "Arnold Walker" <arnoldwal...@consolidated.net>
> > wrote:
> >> "Fran" <Fran.B...@gmail.com> wrote in message
>
> >>news:1184910484.1...@e9g2000prf.googlegroups.com...
>
> <snip for brevity>
>
> >> The hidden cost is also true of wind turbines as well.
> >> You can look at numerous turbine sites over the years and see that.
>
> > No, I can't. Wind technology is improving each year. Twenty years ago,
> > they weren't built in the right places or to the right scale.
>
> >> Whether you are talking California,Hawaii,or Denmark with the large farms
> >> .
> >> And abandoned turbines littering the land scape aren't exactly clean
> >> power
> >> either.
>
> > Much better than abandoned nuclear plants.
>
> Oh puh-lease! Show me a nuclear plant where the owners have just filed
> bankruptcy and walked away leaving the plant completely 'abandoned'. Sure,
> some nucs have been shutdown. But the plant isn't 'abandoned' for the
> government to step in and clean it up or left rusting like several wind
> plants have.
>
If the plant is sitting there idle, and off limits for safet reasons,
I'd say "abandoned" was a fair term. Certainly, it's no less
"abandoned" than a non-functional windfarm -- which is a doddle to
make safe by comparison.
> >> And as to your price for the power ...why do you think wind power is
> >> priced
> >> higher than
> >> conventional power generation.
>
> > Because it doesn't get the kind of price support that nuclear energy
> > gets?
>
> Another red herring. How much funding do nucs get from the feds? The
> recent energy act promises to help fund the first few new plants if they
> ever get built, but none of that has happened yet. You think the government
> is subsidizing nucs somehow?
>
Take a look at the Energy Policy Act of 2005. Direct and indirect
subsidies run into the billions. Even more when you count Price-
Anderson indemnity outside the US.
> Wind and PV *do* get significant support from the government in the form of
> subsidies, 'green' tax breaks and 'renewable' tax breaks.
Nothing like nuclear though. I wonder what 6 or so billion up front
and a couple of billion each year would do the price.
> Yet it is still
> expensive. Some of the expense is *probably* because the investors want a
> short amortization of the capital. Such facilities don't yet have a very
> good track record for operating 40+ years. And investors in general are
> more inclined to seek short-term results then what they were willing to
> accept 30 years ago.
>
> >> Or for that matter wind and solar needs
> >> government price supports in some fashion.
>
> > The Energy Policy Act sets out massive subsidies for nuclear energy.
>
> Which have not yet been utilized. But their are 104 nucs already running
> today. Don't you see a disconnect there?
>
You're not counting Price Anderson are you?
>
>
>
>
>
>
> >> In spite, of being some ot the oldest forms of power ....both have been
> >> around before electricity came into
> >> general.
> >> For small villages,the biomass power is best in the first round.As the
> >> initial infrastructure is established.
> >> In highly industrialize countries like Japan, land is at a high enorgh
> >> prime, the power plant had best offer
> >> much better return than wind does on a given area.
>
> > Japan is one of the least stable places on the face of the Earth.
>
> >> Given the earthquake factor niether windmills or solar would survive a
> >> 6.6
> >> quake ,much less do as well as the reactor in this thread.
>
> > But they needn't all be in the same place. You may not have heard, but
> > Japan is actually an archipeligo -- composed of about 4000 islands.
> > The turbines in the vicinity of the quake may well have been put out
> > of action, but the cost of restoring them would have been piffling.
>
> 'Piffling'? The cost of restoring them would be on par with the original
> cost to build them.
No, it wouldn't. To begin with not all of the capacity would have been
knocked out -- it's spread remember? Secondly, you don't have to
repurchase the land, build access roads, build new transmission lines.
You replace the towers that have been damaged.
> There wouldn't be much salvage. The nuc plant however
> retains most of its capital value. Even if it needs several million dollars
> in repairs, that isn't bad compared to the total investment.
>
That's far from clear. It's far from certain that this won't be a
write off.
> > There would have been no panic. They could have been back up within
> > weeks and maybe less, and all the while, all the others would still be
> > working.
>
> "weeks"?? You seem to think you could just dig the blades up out of the mud
> and re-install them? Or maybe you just trot on down to the local BIG_BOX
> store and order up some replacements? Seriously, if a tower fell from a
> quake, the hub and blades would probably not be salvagable except as scrap
> copper and steel. You'd be looking at getting into the manufacturer's sales
> queue and whatever lead-time they have.
>
It's not passenger aircraft we're doing here. The designs and specs
are all done. No manufacturer is going to want to delay a minute
longer on a deal like that.
Fran
Fran
1. I've never asserted that wind was the total solution.
2. Off shore marine turbines and above sea level winds aren't affected
by land area
3. Tidal could also make a contribution
4. Natural gas and biomass plants seem also to be an obvious solution,
given the massive population densities
5. The latest generation of coal fired plants using syngas, could be
an important component in the system, especially if coupled with flue-
waste collection technologies.
Fran
Vaughn Simon
>
> Take a look at the Energy Policy Act of 2005. Direct and indirect
> subsidies run into the billions. Even more when you count Price-
> Anderson indemnity outside the US.
The entire power industry is steeped in public subsidy. Who financed
Hoover dam? Who pays for the damage from coal plants emissions? How much PV
industry would we have without subsidy?
Vaughn
Fran
wrote:
> "Fran" <Fran.B...@gmail.com> wrote in message
>
> news:1185159050.0...@i13g2000prf.googlegroups.com...
>
>
>
> > Take a look at the Energy Policy Act of 2005. Direct and indirect
> > subsidies run into the billions. Even more when you count Price-
> > Anderson indemnity outside the US.
>
> The entire power industry is steeped in public subsidy.
True
> Who financed
> Hoover dam?
I've used this very example myself elsewhere in usenet.
> Who pays for the damage from coal plants emissions? How much > PV
> industry would we have without subsidy?
My protest isn't against subsidies per se, but merely to argue that
the cost of power is a poor guide to its utility when subsidies of one
kind or another distort the cost.
Whether a subsidy is rational policy depends on whether the income
transfers lead to a just quid pro-quo amongst stakeholders. Sometimes
they do, but often they don't.
Fran
Vaughn Simon
>>
>> > Take a look at the Energy Policy Act of 2005. Direct and indirect
>> > subsidies run into the billions. Even more when you count Price-
>> > Anderson indemnity outside the US.
>>
>> The entire power industry is steeped in public subsidy.
>
>
> the cost of power is a poor guide to its utility when subsidies of one
> kind or another distort the cost.
OK, but it was sounding like you were rejecting one type of power because
it is subsidized by the public. That argument gets you nowhere until you are
advocating a source of power that isn't subsidized.
Vaughn
Paul M. Eldridge
Beyond geographically dispersing wind generation, strengthening
interconnections with neighbouring utilities and more closely coupling
wind resources with hydroelectric storage, real time pricing and
intelligent load management could potentially allow wind energy to
satisfy an increasingly larger share of our electricity needs.
Here in Canada, virtually all utilities are winter peaking and, by
happy coincidence, wind capacity is greatest during these cold winter
months. On the east coast, annual wind capacity factors generally
fall in the range of 30 to 40 per cent, whilst winter numbers come in
at 40 to 50 per cent and above.
Larry Hughes et all have come up with a novel idea of combining wind
energy with electric thermal storage (ETS) heaters. This approach
offers two key benefits. One is that it has the potential to reduce
system peak by shifting a portion of the residential and commercial
heating loads to off-peak hours (these loads can be curtailed during
peak times and available wind resources redirected to serve other
needs). Secondly, with two-way intelligent controls, these thermal
storage heaters can be recharged/topped up anytime surplus wind energy
is available. With two-way communication, excess energy can be
allocated on the basis of greatest need (i.e., provided to those
storage heaters with the lowest state of charge) or, alternatively,
auctioned off to the highest bidder, as determined by various price
parameters set by each user. In either case, wind availability in
large part shapes the heating load, so that supply and demand remain
better matched at all times.
For more information on this, see:
http://dclh.electricalandcomputerengineering.dal.ca/enen/2006/IGEC2-137.pdf
To a somewhat lesser degree, electric water heaters could be tied to
available wind. Again, with two-way communications and fuzzy logic
controls, these loads can be actively managed with little or no impact
to the end user. Within acceptable limits, water temperatures within
these storage cylinders would be allowed to rise and fall in sympathy
with available supplies; a tempering valve would help facilitate this
and, at the same time, ensure proper safety. Periodically boosting
storage temperatures above 60C might also help kill the legionella
bacteria commonly found in these tanks.
Duel fuel furnaces and boilers are one more possibility. Oil is the
dominant heating fuel in Atlantic Canada. Two-thirds of all homes in
Nova Scotia are heated with oil and this number climbs to 4 out of 5
in the case of PEI. At this time, heating oil retails for $0.85 to
$0.90 a litre; assuming 80 per cent conversion efficiency, the cost of
oil heat is a little over $0.10 per kWh(e). Nova Scotia Power's
standard domestic rate is $0.1067 per kWh and its off-peak ETS rate is
$0.0534. Assuming similarly attractive rates are offered to duel fuel
customers, excess wind energy could be used to displace fuel oil in
homes equipped with duel fuel heating systems.
For summer peaking utilities, commercial ice storage cooling systems
are an attractive option. So too residential a/c, water heater and
clothes dryer load controllers.
Cheers,
Paul
Arnold Walker
How many windmills have been built in the last 5000 years?
So what is that breakeven number on windmills?
How much more technology development do they need in order to work?
Is this a good reason to discount other energy sources?
Or is your answer, all about political feel good instead of results.
>
>> How much will all that transmission line cost to maintain?
>
> It depends. Presumably, the nuclear plant sends energy to these
> islands already via transmission lines. They cost what they cost.
>
>> Especially if
>> you plan to size them larger than the wind turbine capacity to accomodate
>> wave/tidal.
>>
>
> Well aren't they currently taking the output of the nuclear plant?
>
>> In a country like Japan, it seems wave tide would make a good
>> contribution
>> if the facilities can be 'hardened' against tsunami.
>>
>
> True
>
>> Let's face it, Japan has some serious challenges to their energy economy.
>> With no significant fossil fuels and limited land resources they need to
>> look towards the sea (as they have traditionally done for their food
>> supply). Something like OTEC might work well if it can be 'hardened'
>> against the frequent quakes.
>>
>
> True, it might.
>
> Fran
>
>
----== Posted via Newsfeeds.Com - Unlimited-Unrestricted-Secure Usenet News==----
Arnold Walker
In some
> settings, nuclear energy is going to be well short of the best option
> on a whole range of grounds. In others of course, utility would demand
> it. There's little doubting that the high capital cost of nuclear
> energy implies a massive slice of the non-coal market, and to that
> extent, some of the rubbishing of alternatives by the nuclear
> bandwagon people reflects their fear that this nibbling away of this
> sector could make nukes unviable.
fear
Needless to say, umbrage is taken on
> the other side and that can skew debate away from sober analysis.
>
> My own predisposition, all else being roughly equal, is for localised
> power generation, and for solutions that leave local communities in a
> good position to control this important resource. I favour solutions
> that promote equity, and that can deliver benefits now when they are
> needed rather than 15 years down the track. As someone who favours the
> liberation of working humanity, I'm bothered by energy options that
> involve that part of humanity bearing the burden of harm if the things
> goes awry. Since, in practice, nuclear energy plants, and the
> materials they use require the highest level of protection, the choice
> of nuclear energy necessarily comes with all sorts of "national
> security" pack-ins, which, by implication, anyone accepting it has to
> endorse. If you will the end, you must will the means, plainly.
>
> Nuclear energy, by definition, can rarely meet these standards. At the
> very least, a transparent debate needs to take place which weighs
> these considerations against the benefits of the technology. I don't
> say it's impossible to meet these standards, but they should be met
> before someone advocates it.
Which also gets to, why there is no energy policy in general.....much less
nuke
policy being what it is.
We have energy in general needs growing,alternatives are still failing to
meeting that demand.
So NIMY refineries,coal gasifiers,nuke ,drilling existing oil,hydroelectric
dams, and anyother shortterm fix while
alternatives limp at best online.If that is noticed there a pat answer about
conserving with full
knowledge that energy is the driving force of society.Part of the reason
third world countries are in the pits.
Is lack of energy.In addition to governments like Mexico that are resource
rich,but held back by government
corruption.That corruption is so intense in some countries that no level of
help will turn them around from
poverty at the hands of a greedy "elite".Who have in times past rode thier
country into the ground after the European colony
countries pulled out (think virtually the entire African continent on that
one.).That elite will also sale the food and seed sent as aid by
the world community to help the people under them.Because thier pockets are
more important than the folks dieing for lack of food.
You can see some of that socialist mind set filtering into the energy
lobbies.Where words almost never match the view...the reason for PC.
>
>> I read both Wasseman and Nader's totally
>> emotionally and ill-informed (see: Helen Caldicott) spews on
>> counterpunch.com. Fran should be writing for them, not these guys.
>
> They wouldn't like what I had to say.
>
> Fran
>
>
----== Posted via Newsfeeds.Com - Unlimited-Unrestricted-Secure Usenet News==----
Arnold Walker
"Mauried" <mau...@tpg.com.au> wrote in message
news:46a4118a...@news.tpg.com.au...
is so high that
that you see an instant replay of New York City versus the rest of the
country, only worse.
They have something on par with a small townhouse and pay like we do on
commerical property.
Part of the reason you see farms mixed in with the town, sort like the diary
farms in Los Angelos.
Commerical properties like for the windfarm would be upwards of 1million
dollars per acre for the
grass or weeds in that lot.Much less the red tape and permits,etc. for the
construction.Remember
we are talking a country the has mandatory five year limits on motor vehicle
life and a learner Triangle on the
back of the car ....the first three to five years you drive in that country.
And energy has no less government
"interest" on regulations,taxes,and fees.
daestrom
No, the difference between a shutdown nuc and an 'abandon' wind farm is many
and various.
Nucs in the US that are shutdown are 'decommissioned'. That means the plant
is disassembled and disposed of while the land is returned to a 'green
field' state. Buildings disassembled, cooling towers dismantled, most
radioactive material removed (Big Rock still has spent fuel in a much
smaller storage area with armed guards). If there are armed guards and
technicians maintaining what little remains, it isn't 'abandoned'. As long
as there is radioactive material on the premises, the licensee or its
decendant is required by law to maintain the storage facility.
Look at Maine Yankee, Yankee Rowe or Big Rock point for examples. Big Rock
is in a bit of a political problem right now because the state and locals
want to place the land in public domain and make a park out of it, while
others want to develop it into an elite housing development with $1M lake
shore properties. Funny how people are fighting over the right to *use* the
land that a former nuc plant sat on.
While some wind-farms have been totally 'abandon' by the owners. The local
government siezed it for non-payment of taxes and taxpayers don't want to
pay to remove the rusting eyesores. So they sit there, a yoke around the
local government's neck, trying to figure out what to do with it.
Now do you see the difference between 'abandoned' wind farm and a
decommissioned nuc plant?
>
>> >> And as to your price for the power ...why do you think wind power is
>> >> priced
>> >> higher than
>> >> conventional power generation.
>>
>> > Because it doesn't get the kind of price support that nuclear energy
>> > gets?
>>
>> Another red herring. How much funding do nucs get from the feds? The
>> recent energy act promises to help fund the first few new plants if they
>> ever get built, but none of that has happened yet. You think the
>> government
>> is subsidizing nucs somehow?
>>
>
> Take a look at the Energy Policy Act of 2005. Direct and indirect
> subsidies run into the billions. Even more when you count Price-
> Anderson indemnity outside the US.
>
Try again. How many of the current generation of nucs have benefited from
the 2005 act? None.
Read up some more on Price-Anderson. The nucs pay an annual fee to the
government for the 'priviledge' of insuring themselves. Each reactor
operator is required by P-A to show the financial ability to pay over $200M
each for any accident that impacts the general public safety. With 104
reactors, that's over $20 B of private funds that must be available for any
reactor incident before public tax dollars would be touched. Some may say
that in a Chernobyl-type accident that wouldn't be enough. Yet the P-A act
did not require *any* payments for TMI. Basically the P-A allows / requires
separate reactor owners to pool together to 'self-insure'. If *any* reactor
in the US has an accident, *all* US reactor owners pay for damages. And for
that 'priviledge', they get to pay the federal government a hefty 'premium'
every year regardless of any accidents.
<sarcasm>
Yeah, paying a premium to the feds and having money idle in escrow for some
other reactor's accident sure does lower the cost of nuclear, I can 'see'
your point.
</sarcasm>
>> Wind and PV *do* get significant support from the government in the form
>> of
>> subsidies, 'green' tax breaks and 'renewable' tax breaks.
>
> Nothing like nuclear though. I wonder what 6 or so billion up front
> and a couple of billion each year would do the price.
???
You might try to use some real numbers. And divide them by MW-hours
generated to see what that really comes down to.
>
>> Yet it is still
>> expensive. Some of the expense is *probably* because the investors want
>> a
>> short amortization of the capital. Such facilities don't yet have a very
>> good track record for operating 40+ years. And investors in general are
>> more inclined to seek short-term results then what they were willing to
>> accept 30 years ago.
>>
>> >> Or for that matter wind and solar needs
>> >> government price supports in some fashion.
>>
>> > The Energy Policy Act sets out massive subsidies for nuclear energy.
>>
>> Which have not yet been utilized. But their are 104 nucs already running
>> today. Don't you see a disconnect there?
>>
>
> You're not counting Price Anderson are you?
>
No, and you shouldn't either. Learn what Price-Anderson really is before
you speak about it.
>> >> In spite, of being some ot the oldest forms of power ....both have
>> >> been
>> >> around before electricity came into
>> >> general.
>> >> For small villages,the biomass power is best in the first round.As
>> >> the
>> >> initial infrastructure is established.
>> >> In highly industrialize countries like Japan, land is at a high enorgh
>> >> prime, the power plant had best offer
>> >> much better return than wind does on a given area.
>>
>> > Japan is one of the least stable places on the face of the Earth.
>>
>> >> Given the earthquake factor niether windmills or solar would survive a
>> >> 6.6
>> >> quake ,much less do as well as the reactor in this thread.
>>
>> > But they needn't all be in the same place. You may not have heard, but
>> > Japan is actually an archipeligo -- composed of about 4000 islands.
>> > The turbines in the vicinity of the quake may well have been put out
>> > of action, but the cost of restoring them would have been piffling.
>>
>> 'Piffling'? The cost of restoring them would be on par with the original
>> cost to build them.
>
> No, it wouldn't. To begin with not all of the capacity would have been
> knocked out -- it's spread remember? Secondly, you don't have to
> repurchase the land, build access roads, build new transmission lines.
> You replace the towers that have been damaged.
>
You replace the towers, the hub, the blades and the transmission line. This
is not 'piffling'. About the only thing you do get to avoid is the land
cost (*thats* a 'piffling' amount of the original construction cost). Some
units may not be damaged if they really are spread out over 200 miles, but
every one that falls will need replacement and be off-line for more than 'a
couple of weeks'.
>> There wouldn't be much salvage. The nuc plant however
>> retains most of its capital value. Even if it needs several million
>> dollars
>> in repairs, that isn't bad compared to the total investment.
>>
>
> That's far from clear. It's far from certain that this won't be a
> write off.
At this point, any speculation either way is just that, pure speculation.
>
>> > There would have been no panic. They could have been back up within
>> > weeks and maybe less, and all the while, all the others would still be
>> > working.
>>
>> "weeks"?? You seem to think you could just dig the blades up out of the
>> mud
>> and re-install them? Or maybe you just trot on down to the local BIG_BOX
>> store and order up some replacements? Seriously, if a tower fell from a
>> quake, the hub and blades would probably not be salvagable except as
>> scrap
>> copper and steel. You'd be looking at getting into the manufacturer's
>> sales
>> queue and whatever lead-time they have.
>>
>
> It's not passenger aircraft we're doing here. The designs and specs
> are all done. No manufacturer is going to want to delay a minute
> longer on a deal like that.
>
It's a matter of production capacity. Yes, the manufacturer can
'cookie-cutter' them out just as fast as they produce them. But guess what,
they are *not* sitting around idle waiting for your disaster-replacement
order. They're already building units for others. They have production
schedules out for a year or more. They've got a staff out there marketing
and scheduling all the time to keep the production floor gainfully employed.
Are they going to tell their other customer in Norway (or whereever),
"Sorry, we stopped work on your order because they had an earthquake in
Japan. We'll get back to it in a couple of months when we've finished
building them some replacements."
Maybe if the Japanese come up with a hefty 'expeditition fee'. But it would
have to cover all the 'penalty fees' for not delivering on time to Norway.
Not likely though. More likely is your replacement order goes on the bottom
of the pile and won't be filled until all the other orders ahead of you are
filled.
daestrom
Fran
What you're asking here needs clarification.
> ......at least in theory.
> How many windmills have been built in the last 5000 years?
I wouldn't know. Quite a few I'd say.
> So what is that breakeven number on windmills?
Pretty good, whatever that means. I'll bet pretty much every
competently erected windmill has paid for itself. You can't say that
about nuclear.
> How much more technology development do they need in order to work?
They all work. Better storage and reticualtion technology would help
them work even better, obviously.
> Is this a good reason to discount other energy sources?
No, and if you'd bothered to read the bits of my posts that don't suit
your own caricature (expressed below) you'd know that.
> Or is your answer, all about political feel good instead of results.
>
When the results are good, I feel politically good.
Fran
Fran
wrote:
>
> To a somewhat lesser degree, electric water heaters could be tied to
> available wind. Again, with two-way communications and fuzzy logic
> controls, these loads can be actively managed with little or no impact
> to the end user. Within acceptable limits, water temperatures within
> these storage cylinders would be allowed to rise and fall in sympathy
> with available supplies; a tempering valve would help facilitate this
> and, at the same time, ensure proper safety. Periodically boosting
> storage temperatures above 60C might also help kill the legionella
> bacteria commonly found in these tanks.
>
> Duel fuel furnaces and boilers are one more possibility. Oil is the
> dominant heating fuel in Atlantic Canada. Two-thirds of all homes in
> Nova Scotia are heated with oil and this number climbs to 4 out of 5
> in the case of PEI. At this time, heating oil retails for $0.85 to
> $0.90 a litre; assuming 80 per cent conversion efficiency, the cost of
> oil heat is a little over $0.10 per kWh(e). Nova Scotia Power's
> standard domestic rate is $0.1067 per kWh and its off-peak ETS rate is
> $0.0534. Assuming similarly attractive rates are offered to duel fuel
> customers, excess wind energy could be used to displace fuel oil in
> homes equipped with duel fuel heating systems.
>
> For summer peaking utilities, commercial ice storage cooling systems
> are an attractive option. So too residential a/c, water heater and
> clothes dryer load controllers.
>
> Cheers,
> Paul
Interesting post, Paul. Demand management is certainly one approach to
making best use of intermittent energy sources. Water pumping to
catchments is something that can be done off peak or when surplus
power is available.
Fran
daestrom
Actually, there is another type that is often used for the large units. It
consists of a wound-rotor motor with electronics controlling the power flow
into/ out of the wound rotor. By controlling the current / frequency on the
three-phase rotor winding they control the slip speed of the rotor. So the
rotor speed can vary over a pretty good range and still have 60 Hz (or 50
Hz) output from the stator winding. One paper on the subject stated that
careful control algorithms could extract something like 40% of the total
power from the rotor winding and the other 60% from the stator winding.
This system allows operating with a fixed gear-box and yet a range of blade
speeds.
daestrom
Fran
<vaughnsimonHATESS...@att.FAKE.net> wrote:
> "Fran" <Fran.B...@gmail.com> wrote in message
Fair comment.
Actually, what I believe could be a better approach would be to try
and quantify in broad terms, the scope and ubiquity of the
quantifiable harms per unit of productive ouput of each industrial,
agricultural, service or retail activity and attach a cost to each
that reflected the cost of an adequate remedy, plus, say, a 5%
surcharge to cover R & D, auditing, tendering for solutions etc.
On the other side of the equation, organisations could tender for the
business of supplying the remedies or doing the R & D and when that
process was sorted out, there would not be a lot of scope for people
to argue that this was just a tax grab.
Of course, once that were done, one could then decide, in a
transparent way, the extent to which some of the cost of meeting those
obligations could be borne by the community at large or transferred to
future generations on the basis that they too were likely to be
beneficiaries.
If that were done in a rigorous way, getting the energy mix right
ought to be a lot easier.
Fran
Fran
> http://www.channelnewsasia.com/stories/afp_asiapacific_business/view/...
>
> TOKYO : Japan plans to keep its largest nuclear plant closed for at
> least a year amid a nationwide scare after it leaked radioactive water
> following an earthquake, a newspaper said Thursday.
>
> Tokyo Electric Power Co., which operates the sprawling Kashiwazaki-
> Kariwa plant northwest of the Japanese capital, has already asked
> other companies to pitch in to meet the metropolis's electricity needs
> in peak summer months.
>
<snip>
This just in:
Japan crude imports to rise on extra demand
||||
TOKYO (MarketWatch) -- Japan's crude oil demand is expected to rise on
year in August as refiners are likely to step up imports to meet extra
demand from utilities for sweet crude and low-sulfur C-fuel oil after
Tokyo Electric Power Co. (9501.TO) shut its Kashiwazaki-Kariwa nuclear
power plant last week following a strong earthquake.
This may provide a substantial boost to Japan's crude demand for
several months or even longer, analysts said.
"As long as Kashiwazaki-Kariwa remains shut, the extra demand will
continue," said Toshinori Ito, an analyst with UBS Securities Japan
Ltd.
Tepco and other utilities will have to boost electricity production at
their thermal power plants to meet summer electricity demand amid a
strong economy and forecasts of a hot summer.
Other utilities not only have to sell power to Tepco, but also to
Hokuriku Electric Power Co. (9505.TO), whose Shika plant in western
Japan is expected to remain closed throughout this fiscal year ending
March 2008 due to the coverup of an accident and turbine flaws.
Japan's crude demand has mostly been lower on year in recent years
because of widely used energy-efficient technologies such as small and
hybrid cars, as well as a shift to natural gas among large corporate
users for in-house power generation and boiler fuel.
Japan's imports of crude oil and condensate in June fell 0.9% on year
to 19.08 million kiloliters or 4 million barrels a day, the Ministry
of Finance said Wednesday.
This could give hope to Japanese refiners, who have been suffering
from excessive refining capacity and narrowing margins.
"They have enough capacity to produce the necessary C-fuel," said
Ito.
This will also have a good influence on their earnings, Ito said, as
costs will become lower thanks to higher refinery operating rates,
though the positive effect would be limited due to thin margins.
Impact On Sweet Crude Price
However, there may be a problem with purchasing sweet crude, said
Yoshihiko Inoo, an analyst with futures brokerage Tokyo Comwealth Inc
who was previously in charge of domestic oil products sales at a major
refiner.
"Since Japanese utilities can burn only low-sulfur C-fuel and sweet
crude, it will become hard for them to find the necessary amounts of
such crude while demand is surging," said Inoo.
"I don't think all sweet crude will be sold out, but prices will
rise."
Fumiaki Watari, chairman of Nippon Oil Corp. (5001.TO), Japan's
largest refiner by capacity, said last week he expects monthly demand
for C-fuel to increase by 400,000 kiloliters and by 300,000 kiloliters
for crude if the Kashiwazaki-Kariwa plant remains shut. The crude
increase is equivalent to around 62,000 barrels a day.
Nippon Oil plans to produce an additional 50,000 kiloliters of C-fuel
in August and import another extra 100,000 kiloliters or 629,000
barrels of sweet crude, mainly from Indonesia, to meet demand from
Tokyo Electric Power, The Nikkei said in its Wednesday morning
edition.
||||
Fran
dave.w...@comcast.net
>
> ||||
>
> Fran
They have already started up just about every peaker unit in the
Island. Among the many "lessons" people are going to talk about is the
amount of carbon spewed into the air to replace the zero CO2 emmiting
nuclear. Hopefully they will be able to restart the units as soon as
any problems are corrected.
David
Fran
Of course, had they not been dependent on nuclear and had a better
spread of energy sources -- wave, wind, ground heat, biomass, NG etc,
then this would not have arisen.
Indeed, even if they had wanted to use nuclear, they are close enough
to Russia or China to have a plant there and transmit the energy
across.
That might have been politically embarassing of course; far better to
spend billions constructing a nuclear plant in an area of extreme
tectonic instability
Fran
Vaughn Simon
> Indeed, even if they had wanted to use nuclear, they are close enough
> to Russia or China to have a plant there and transmit the energy
> across.
>
> That might have been politically embarassing of course; far better to
> spend billions constructing a nuclear plant in an area of extreme
> tectonic instability
Siting a power plant in another country that may have entirely different
political motives and very different safety standards carries its own risks that
could be far more serious than the tectonic ones.
Vaughn
Mauried
Id love to see the undersea power cable carrying the 8 GW.
and the cost of building it.
No country is going to hand its energy security to another country,
no matter what the politics may be.
Anthony Matonak
...
> No country is going to hand its energy security to another country,
> no matter what the politics may be.
I'm not so certain about that. The United States imports a lot of its
energy from other countries. It therefore has handed over a portion of
its energy security to these other countries. It's probably not the
only country to have done so.
Anthony
dave.w...@comcast.net
>
> - Show quoted text -
They should of not of built 8-cluster NPPS, no more than 4 or even 2.
Cheaper by the dozen, essentially. Take a 7.5 earthquake, build to
that, not 6.2. Dumb, agreed.
As stated previously, they have to start using coal and oil until
these units are fixed and/or retrofitted. Fortunatlly there was no
damage to the reactors, as far as we know, yet. They could be back up
an running in a few weeks or a few months.
Building them on the Asian mainland and wheeling the power under a 100
km of water, for that much power or more ,is simply not doable.
David
Corrupted Nutsack
>>
>> They have already started up just about every peaker unit in the
>> Island. Among the many "lessons" people are going to talk about is the
>> amount of carbon spewed into the air to replace the zero CO2 emmiting
>> nuclear. Hopefully they will be able to restart the units as soon as
>> any problems are corrected.
>
> Of course, had they not been dependent on nuclear and had a better
> spread of energy sources -- wave, wind, ground heat, biomass, NG etc,
> then this would not have arisen.
>
> Indeed, even if they had wanted to use nuclear, they are close enough
> to Russia or China to have a plant there and transmit the energy
> across.
Jesus, what a fucking nitwit you are.
daestrom
"daestrom" <daestrom@NO_SPAM_HEREtwcny.rr.com> wrote in message
news:46a53e2e$0$3110$4c36...@roadrunner.com...
OOPS, After posting this I went back to refresh my own memory on P-A and
found that I was mistaken. The act requires any reactor owner to pay the
first $300M and then all US reactors pay about $98M each towards public
damage from an accident for a total of about $10B, not the $20B I posted
above.
If damages exceed that, then the federal government will then decide how to
proceed. They may use taxpayer money, or they may simply raise the 'reactor
owner' contributions. Since it's never happened, we don't really know what
might happen in that case.
daestrom
P.S. Curiously, the DOE has paid money out for public damages under the
P-A. Not because the P-A asked the federal government to pick up the cost
of some commercial reactor accident, but because the DOE is included as a
'reactor-owner' right along with the private sector. And the DOE reactors
have caused some public damage so the DOE (as 'reactor-owner') was on the
hook for the first $300M. The amount they paid out so far is something like
$65M
daestrom
While I agree that energy diversity is a good plan, Russia has already
demonstrated a willingness to use energy for political purposes with it's
natural gas supplies to eastern Europe.
China might be willing at least in principle, but they'd probably do it with
a lot of coal and let the smog drift over Japan. China's air pollution
record isn't all that great. And besides, they have their own burgeoning
economy to feed.
Moving that much power that sort of distance would require an HVDC link, you
just can't transmit that kind of power directly with AC.
The question of centralized versus de-centralized has been around for years.
Yes, putting a large number of plants in close proximity means they are
susceptible to a common event (such as the recent earthquake). But
de-centralized comes with some problems of its own, not the least of which
is much higher transmission costs (both capital and operational).
Transferring a couple of GW of power over a couple hundred miles from each
point of the compass is *not* for the faint at heart.
daestrom
daestrom
But what price do you put on the various factors? Whatever number you use
for the 'price per mile of right-of-way for transmission line', or the
'price per unobscured sunrise', or 'price per ton of mercury discharged to
the air from fossil fuels'; the number would be highly subjective and open
to endless argument and debate. To an asthmatic, even a small amount of
particulate discharge is too much, for an naturalist even just a few acres
per mile of transmission is too much land clearing.
I agree with the idea in principle (have each technology reflect its total
cost directly and not have 'hidden costs'), I just don't see how it can be
achieved. Get ten people on a committee and they can't even decide what
colors to use for decorating a wedding hall, much less something of this
complexity.
daestrom
Fran
That's a debate that is urgently necessary. In some cases, it goes to
remedy. As you say, reconciling the particular needs of minorities
with the needs of the mass of the population is the very stuff of
politics.
Plainly, what impacts one defines as sufficiently harmful to require
mitigation or adaptation is a political question, as is the question
of the costs one wishes to bear and who should bear it. What price
does one put on sulphur or FPM, or aromatics, or CO or Hg or ozone?
What value does one put on the health of watercourses and the ocean
adjacent to a land mass?
Still, I like the idea of asking the fundamental question -- how much
would it cost to eliminate or mitigate this or that risk, or
compensate people for accepting it, and working backwards from there
to target those contributing to it. At the very least, the true rate
of subsidy each industry gets from what may be broadly called "the
commons" would be clear.
Right now, these externalities are hidden from public view which
distorts the perception of the various options in public discourse.
Yes, there would be a bit of a bunfight, but in some cases, a measure
targeting one harm considered serious would likewise deal with another
coextensively. For example, substitution of biodiesel for petrodiesel
would reduce total hydrocarbons (not just CO2) and specifically CO,
FPM, and so forth. There would be a marginal increase in tailpipe NOx,
but in lifecycle terms, less - and even these could be addressed by
the catalytic converter. Alcohol fuels produce pretty much nothing but
CO2 and water at the tailpipe. Of course, all fossil inputs (including
into biofuels) would be reflected in the cost of the output. This
would affect uranium, coal and everywhere else these are used.
More effectively designed transport systems, measures aimed at abating
the concentration of private vehicles in city centres (e.g having
major carparks on the approaches to the city centre with shuttle buses
to take people to and from the city) could massively reduce the least
energy and pollution-efficient passenger miles travelled in ways that
actually saved people money and time and stress. Such a measure would
also reduce the rate of vehicle collision and road trauma, so there
would be spin off benefits everywhere. Conceivably, health and motor
vehicle insurers could come to the party on the underlying
infrastructure.
I'm a socialist of course, but that aside, the lack of imagination at
government level is simply breathtaking.
Fran
Fran
wrote:
> "Fran" <Fran.B...@gmail.com> wrote in message
Not if they proposed a joint venture operation -- say a large nuclear
plant. In any event, I was being deliberately algebraic. It doesn't
*really* occur to me that as things stand, this would be politically
feasible. China and Japan are rivals. Japan is aligned with the US
which is tilting against China on trade matters. Japan's ruling
coalition would hate to have to be beholden to China.
On the other hand, if what we were discussing was the configuration of
the power grid of some entity like "the Confederated Socialist
Republics of East Asia" then this would be entirely plausible.
> China's air pollution
> record isn't all that great. And besides, they have their own burgeoning
> economy to feed.
>
So?
> Moving that much power that sort of distance would require an HVDC link, you
> just can't transmit that kind of power directly with AC.
>
True
> The question of centralized versus de-centralized has been around for years.
> Yes, putting a large number of plants in close proximity means they are
> susceptible to a common event (such as the recent earthquake). But
> de-centralized comes with some problems of its own, not the least of which
> is much higher transmission costs (both capital and operational).
Which are largely offset by lower transmission losses over great
distances, and the benefits of a more stable network.
> Transferring a couple of GW of power over a couple hundred miles from each
> point of the compass is *not* for the faint at heart.
But still very doable. It's done all the time in NSW.
Fran
Mauried
Where is it done.
What power line in NSW carries a couple of GW.
What voltage and current rating is it using.
Don Kelly
Governmental policies are affected by a "go away and someone else will have
to deal with this in the future" mentality (hard decisions cost votes).
Waffling between what the relatively ignorant public think is right and
any solid advice from knowledgeable sources depends on which gets the most
votes. Otherwise the nuclear "problems" would have been settled long ago.
I have no problem with your being socialist but I do have a problem with
"political" solutions to technical problems- you have lawyers dealing with
resource management or cigarette salesmen dealing with health problems
because they have managed to schmooze the public enough to get elected-maybe
where you live it is better but I doubt it.
--
Don Kelly dh...@shawcross.ca
remove the X to answer
Don Kelly
We have, locally, a person who is, among other things, anti-nuclear, based
on his perception of unreliability and all the other garbage. In addition he
proposes local wind, solar, etc to overcome what he calls the fragility of
the grid. However he wants to keep the most fragile part- local distribution
and assumes that the necessary diversity would still exist. IGNORANCE IS
BLISS. Take a problem-remove all annoying practical factors and then come up
with a solution which is based on wishful thinking.
As for Japan- I assume that they are glad that they have planned for
contingencies and have the capability to handle them- even if it involves
short term costs. Could wind or solar have coped? Probably not. So-diverse
sources of different kinds are needed -including the dread nuclear
plant(which would, I assume, be the source that the Japanese would be much
more uncomfortable with than North Americans) .
--
Don Kelly dh...@shawcross.ca
remove the X to answer
----------------------------
>
Mauried
There seems to be a huge lack of understanding of practicality.
I was watching a TV show last week discussing whether Nuclear Power
in Australia was going to be a viable option,and one of the so called
experts on the discussion panel simply dismissed it as a non goer,
citing that all that was needed was to put solar cells on the roofs of
every house in the country.
Now, whilst this is possible to do from an engineering perspective ,
its totally impossible financially,but this seems lost on a lot of
people.
There also seems to be a strange beleif that the only users of
electricity are people who live in houses and that all thats needed is
to reduce household energy consumption and this solves all the worlds
energy problems.
One other observation is that the people who seem most to be promoting
alteratives like wind, solar, tidal etc , dont have any background in
designing large electricity transmission and generation networks.
Maintaining grid stability , when you start adding large wind farms is
something that no one seems to care about.
Fran
> ----------------------------"Fran" <Fran.B...@gmail.com> wrote in message
All problems of social organisation represent an interplay of what
most recognise as political and technical matters. One must, of
course, start from what is technically feasible, and then begin to
assess risks, costs and benefits. This latter process of course, is
substantially political because how one values benefits, and what
risks one thinks are acceptable is essentially, a policy question.
> you have lawyers dealing with
> resource management or cigarette salesmen dealing with health problems
> because they have managed to schmooze the public enough to get elected-maybe
> where you live it is better but I doubt it.
And that's because, the claims of democracy notwithstanding, the
system really isn't politically inclusive or even transparent.
Accordingly, it lends itself to just this sort of thing.
Years ago, in the early 1980s, Salter's Duck (apparently 90% efficient
in capturing wave energy) went before a British committee as a model
for energy production in the sea, and despite being demonstrably
feasible, the committee, dominated by the coal and nuclear interests,
saw it shafted, quoting figures that overestimated, by a factor of
ten, the cost of the resultant energy. But the whole thing was kept
quiet. Britain was of course, very keen on nukes for a number of
political reasons -- smashing up the miners' union, trident missiles
and so forth.
Doubtless, Salter's Duck needed more work -- surviving in rough seas
was an issue, but it was certainly promising. Had a mere fraction of
the money that has gone into cleaning up the nuclear mess in Britain
gone into this, one can wonder how much better placed wave technology
would be today.
Fran
daestrom
No. This is a common fallacy, that a large number of small generation units
increases grid stability.
To truly understand this you must define two distinct terms, 'stability' and
'reliability'. 'Reliability' is the chances of a major power outage
happening as a result of some predictable failure. 'Stability' is the
ability of the grid to maintain the key parameters of voltage and frequency
to each load that is supplied during all sorts of conditions of both normal,
abnormal and emergency operation.
A large number of small generating units may seem more 'reliable' since any
single generating unit failure is less likely to cause an overload and
collapse. That's the theory. But the details are crucial. If you swap one
large generating unit that is more than 95% reliable with ten units that are
only 85% reliable, have you really improved? Current technology requires
that the system 'survive' a loss of the largest generating unit. Since
generating units are somewhat centralized and large, this means there must
be sufficient 'spinning reserve' to absorb the transient of losing such
large units. If there were no 'large' units and a larger number of 'small'
units were used, then yes the transient of losing a small unit is less
severe and easier to compensate.
But many large-scale blackouts in the past were not caused by a loss of a
'large' generating unit (at least not initially). The initiating event for
the August 2003 blackout for example was caused by a transmission line
issue. If a large number of 'small' generating units are interconnected by
transmission lines that are just as unreliable as before, then the chances
of a major blackout are probably about the same.
When it comes to 'stability' a large number of independent generating units,
strong together over several hundred square miles with transmission systems
is very difficult to keep stable. Power flow over a dense network of
inter-connecting lines means that power from each generating unit has
multiple pathways to reach the various loads. Controlling just how much
power flows over each line (to avoid overloading any given line) is
complicated now. Increasing the number of generating units and transmission
pathways by a an order of magnitude will not make power flow, voltage and
frequency *more* stable. If anything, it will be less stable.
On the point of transmission losses, they would not be lower for a
de-centralized scheme. By its very nature, a decentralized scheme would
have more transmission lines, not less. And line losses are function of
power carried and distance traveled. While an individual line in a
de-centralized scheme would be carrying less power, there would be more of
them. With centralized, you have one (or a few) large lines carrying some
large amount of power (say 8GW) from point 'A' to point 'B' with losses 'X'.
With de-centralized you have a whole network mesh of smaller lines, each
carrying some smaller amount of power from points 'C' through 'M' with
losses 'c' through 'm'. But the load (8GW) is still the same and the
average distance from generating unit to load is probably higher so losses
are *not* less, if anything they would be more.
>
>> Transferring a couple of GW of power over a couple hundred miles from
>> each
>> point of the compass is *not* for the faint at heart.
>
> But still very doable. It's done all the time in NSW.
Really? Where is this 'couple of GW' line that covers such a distance?
daestrom
Don Kelly
On the other hand, Salter's Duck might simply not have been cost effective
even if all the books were balanced in its favour. There is a tendency to
ignore the drawbacks of such technology and emphasise the drawbacks of
conventional sources.
90% efficient- somewhat questionable from the viewpoint of the mechanics
involved even discounting electrical generation losses. The % probability
of it being destroyed in a major storm is not mentioned.
Could it be that someone applied some hard-nosed engineering analysis and
found that the facts didn't meet the claims?
For example: the tremendous tidal energy available at the Bay of Fundy has
been known for the past 50 years and a pilot plant was built and still is in
operation but no further development has occurred. Oil and nuclear
conspiracies? No- economic and environmental factors combined to put this
well studied project on the back burner. See the parallel?
Certainly there is no reason not to explore the Salter's Duck technology-to
actually establish its performance in real life situations- i.e. build a
large enough pilot plant of sufficient size to show the promise and the
drawbacks-didn't get that far- not due to conspiracies of the oil/nuclear
cartels.
As for putting a cost on environmental factors- this is probably far more
prevalent these days than you think. In fact consideration of environmental
"costs" in the economic dispatch of available generation resources is not a
new idea. Each source has a fuel cost + an environmental "cost" and both can
be considered. The availability of each resource at a given time is also a
concern.
The problem that we have today is delivering the energy -when it is needed-
using the best mix of sources including all forms of "costs" and taking into
account their advantages/disadvantages in the mix. It is not a "wave the
magic wand" sort of thing nor something politicians can legislate (such as
once happened- defining pi as 3.0000..... ).
I have more faith in IEEE, IEE, and other reputable refereed engineering
journals than in what appears in general news reports or political
statements. First of all, the writers know their subject and secondly there
are many knowledgeable people who can and do challenge them.
Fran
> ----------------------------"Fran" <Fran.B...@gmail.com> wrote in message
<snip>
> > Years ago, in the early 1980s, Salter's Duck (apparently 90% efficient
> > in capturing wave energy) went before a British committee as a model
> > for energy production in the sea, and despite being demonstrably
> > feasible, the committee, dominated by the coal and nuclear interests,
> > saw it shafted, quoting figures that overestimated, by a factor of
> > ten, the cost of the resultant energy. But the whole thing was kept
> > quiet. Britain was of course, very keen on nukes for a number of
> > political reasons -- smashing up the miners' union, trident missiles
> > and so forth.
>
> > Doubtless, Salter's Duck needed more work -- surviving in rough seas
> > was an issue, but it was certainly promising. Had a mere fraction of
> > the money that has gone into cleaning up the nuclear mess in Britain
> > gone into this, one can wonder how much better placed wave technology
> > would be today.
>
> > Fran
>
> On the other hand, Salter's Duck might simply not have been cost effective
> even if all the books were balanced in its favour. There is a tendency to
> ignore the drawbacks of such technology and emphasise the drawbacks of
> conventional sources.
>
Regrettably, we are unlikely ever to find out, essentially as a result
of self-serving skullduggery by the fossil energy crowd, aided and
abetted by Thatcher.
> 90% efficient- somewhat questionable from the viewpoint of the mechanics
> involved even discounting electrical generation losses. The % probability
> of it being destroyed in a major storm is not mentioned.
So what we'd really need to do would be some live trial, some
monitoring, maybe put some thought into placement, mooring, shut off
and feathering points, materials etc.
> Could it be that someone applied some hard-nosed engineering analysis and
> found that the facts didn't meet the claims?
If they had, then it's astonishing that nobody mentioned this at the
time. Really, if you're pushing another barrow, having an ostensibly
objective reason for objecting to some rival would have been much less
risky than deliberately falsifying data.
> For example: the tremendous tidal energy available at the Bay of Fundy has
> been known for the past 50 years and a pilot plant was built and still is in
> operation but no further development has occurred. Oil and nuclear
> conspiracies? No- economic and environmental factors combined to put this
> well studied project on the back burner. See the parallel?
>
I'm not up on the issues with Bay of Fundy, but the emotive term
'conspiracy' notwithstanding, one knows how these things go. Baksheesh
rules.
> Certainly there is no reason not to explore the Salter's Duck technology-to
> actually establish its performance in real life situations- i.e. build a
> large enough pilot plant of sufficient size to show the promise and the
> drawbacks-didn't get that far- not due to conspiracies of the oil/nuclear
> cartels.
>
You're more trusting than I am. Let's face it, Thatcher was going to
have nukes no matter what the public interest balance was. Trident and
smashing the miners union rendered all other considerations utterly
moot.
> As for putting a cost on environmental factors- this is probably far more
> prevalent these days than you think. In fact consideration of environmental
> "costs" in the economic dispatch of available generation resources is not a
> new idea. Each source has a fuel cost + an environmental "cost" and both can
> be considered. The availability of each resource at a given time is also a
> concern.
>
I'm yet to see any rigorous example of this policy. Certainly an iron
curtain is drawn around the costs of securing and protecting oil, and
the costs of flaring at oil drill sites. There's pretty much no cost
on coal emissions either. Is anybody looking at the cost of supplying
water to mine operations? Not really. In Australia, water to uranium
miners is free. Tailings? Who cares? Overburden? What's that? Mine
deaths? Is that relevant?
> The problem that we have today is delivering the energy -when it is needed-
> using the best mix of sources including all forms of "costs" and taking into
> account their advantages/disadvantages in the mix. It is not a "wave the
> magic wand" sort of thing nor something politicians can legislate (such as
> once happened- defining pi as 3.0000..... ).
Of course not, but it requires a vision of how to decide where 'the
commons' begin and end, and how to measure and balance up benefits,
costs and risks. Right now, the elites zero rate the commons and
mostly don't even think about it. Until that changes, i.e the
political power of elites is destroyed, nothing of lasting value can
occur.
> I have more faith in IEEE, IEE, and other reputable refereed engineering
> journals than in what appears in general news reports or political
> statements. First of all, the writers know their subject and secondly there
> are many knowledgeable people who can and do challenge them.
Maybe, but their ideas will be taken up only to the extent that they
coincide with the perceived interests of the wealthy.
Fran
Fran
That's the key question though. There's no reason to assume that
smaller units will be less reliable than larger units. Depending on
how they are maintained, it might be that smaller units are looked
after better, or it might not.
> Current technology requires
> that the system 'survive' a loss of the largest generating unit. Since
> generating units are somewhat centralized and large, this means there must
> be sufficient 'spinning reserve' to absorb the transient of losing such
> large units. If there were no 'large' units and a larger number of 'small'
> units were used, then yes the transient of losing a small unit is less
> severe and easier to compensate.
>
Exactly. And remember, a large unit is a much better target for attack
from criminals than a small unit.
> But many large-scale blackouts in the past were not caused by a loss of a
> 'large' generating unit (at least not initially). The initiating event for
> the August 2003 blackout for example was caused by a transmission line
> issue. If a large number of 'small' generating units are interconnected by
> transmission lines that are just as unreliable as before, then the chances
> of a major blackout are probably about the same.
>
That's true, but the effect of those transmission failures on the
system as a whole will be smaller.
> When it comes to 'stability' a large number of independent generating units,
> strong together over several hundred square miles with transmission systems
> is very difficult to keep stable. Power flow over a dense network of
> inter-connecting lines means that power from each generating unit has
> multiple pathways to reach the various loads. Controlling just how much
> power flows over each line (to avoid overloading any given line) is
> complicated now. Increasing the number of generating units and transmission
> pathways by a an order of magnitude will not make power flow, voltage and
> frequency *more* stable. If anything, it will be less stable.
>
Again, it depends on a whole range of factors. Localised demand
management is a pretty important tool, since a lot of power usage is
potentially elastic -- one can choose when to pump water to catchments
and when to stop. Water heaters can be adjusted to take advantage of
times when demand is low, realtive to supply.
> On the point of transmission losses, they would not be lower for a
> de-centralized scheme. By its very nature, a decentralized scheme would
> have more transmission lines, not less.
True, but each unit of energy might have to travel, on average, less
far before being converted into work, Thus, if the typical
transmission distance is under 50 km, losses in transmission are going
to be less that if it's three or four times that. As I understand it,
the need to avoid brownouts at the end of the line means having more
power at the source than those near to the source actually need.
> And line losses are function of
> power carried and distance traveled. While an individual line in a
> de-centralized scheme would be carrying less power, there would be more of
> them. With centralized, you have one (or a few) large lines carrying some
> large amount of power (say 8GW) from point 'A' to point 'B' with losses 'X'.
> With de-centralized you have a whole network mesh of smaller lines, each
> carrying some smaller amount of power from points 'C' through 'M' with
> losses 'c' through 'm'. But the load (8GW) is still the same and the
> average distance from generating unit to load is probably higher so losses
> are *not* less, if anything they would be more.
>
I don't see that. If C -- > M involves typically navigating less
copper than A -- B surely it's the better option. If every significant
source of demand has a generating unit nearby, with the surplus sent
into the grid to the next closests point where there's unmet demand
then surely losses are lower.
>
>
> >> Transferring a couple of GW of power over a couple hundred miles from
> >> each
> >> point of the compass is *not* for the faint at heart.
>
> > But still very doable. It's done all the time in NSW.
>
> Really? Where is this 'couple of GW' line that covers such a distance?
I'll have to get back to you on NSW, but I note that the Chinese are
planning to send 18.6 GW about 2000 km from the Xi,loda Xiangjiabo
power plant. The Benmore Dam in NZ carries 1.2 GW over 500 km. Then
there's that HDC line carrying 3.1 GW 1300 km down the Pacific Coast
from Oregon to California.
Using HVDC is obviously the way to go, particularly under water where
capacitance is high. Basslink uses a submarine cable under Bass Strait
(separating the Australian mainland from Tasmania) nearly 300km long.
Admittedly, it's only carrying half a GW from Loy Yang in Victoria,
but plainly, there's no technical reason why one could not build a
more powerful link, or series of links.
Fran
Don Kelly
"Fran" <Fran...@gmail.com> wrote in message
news:1185678494.3...@e16g2000pri.googlegroups.com...
----
There is a good reason to assume that they will be less reliable-
experience.
-----------
>
>> Current technology requires
>> that the system 'survive' a loss of the largest generating unit. Since
>> generating units are somewhat centralized and large, this means there
>> must
>> be sufficient 'spinning reserve' to absorb the transient of losing such
>> large units. If there were no 'large' units and a larger number of
>> 'small'
>> units were used, then yes the transient of losing a small unit is less
>> severe and easier to compensate.
---------------
Questionable. As small units will be tied through lower voltage lines- one
doesn't feed a 500KV line from a 10MW unit. These lead to gathering points
and retransmission at a higher voltage. Unfortunately the lower voltage
lines are much more vulnerable than the higher voltage lines and the outage
rate will rise. Most outages that you observe are due to outages on the
subtransmission system, not due to the major transmission system or large
generators. Note also that small wind and solar sources will also need
backup.
--------
However the probability of loss of supply in terms of MWH /year may
increase.
Possibly I should redirect you to an old friend who speciality is power
system reliability rather than just say nay (with somewhat more reason than
you have to say yea).
http://books.google.ca/books?id=IJBCJt2jaBQC&dq=power+system+reliability&pg=PA142&ots=KCJ4sTp8Vi&sig=9DCkFxDrDPaVPKVIWQE67gXEuv0&prev=http://www.google.ca/search%3Fhl%3Den%26q%3Dpower%2Bsystem%2Breliability%26btnG%3DSearch%26meta%3D&sa=X&oi=print&ct=result&cd=1#PPA8,M1
>>
>
>
> Exactly. And remember, a large unit is a much better target for attack
> from criminals than a small unit.
------
Not necessarily so. Depends on the stupidity or lack of it that the
criminals show.
-----------
>
>> But many large-scale blackouts in the past were not caused by a loss of a
>> 'large' generating unit (at least not initially). The initiating event
>> for
>> the August 2003 blackout for example was caused by a transmission line
>> issue. If a large number of 'small' generating units are interconnected
>> by
>> transmission lines that are just as unreliable as before, then the
>> chances
>> of a major blackout are probably about the same.
>>
>
> That's true, but the effect of those transmission failures on the
> system as a whole will be smaller.
---------
Not necessarily. Sometimes a small disturbance can have wide reaching
consequences. See the NE blackout of 1964(? year is from memory).
------
>
>> When it comes to 'stability' a large number of independent generating
>> units,
>> strong together over several hundred square miles with transmission
>> systems
>> is very difficult to keep stable. Power flow over a dense network of
>> inter-connecting lines means that power from each generating unit has
>> multiple pathways to reach the various loads. Controlling just how much
>> power flows over each line (to avoid overloading any given line) is
>> complicated now. Increasing the number of generating units and
>> transmission
>> pathways by a an order of magnitude will not make power flow, voltage and
>> frequency *more* stable. If anything, it will be less stable.
>>
>
> Again, it depends on a whole range of factors. Localised demand
> management is a pretty important tool, since a lot of power usage is
> potentially elastic -- one can choose when to pump water to catchments
> and when to stop. Water heaters can be adjusted to take advantage of
> times when demand is low, realtive to supply.
------------
This is not what is meant by power system stability- you are talking about
peak shaving.
---------------------------
>
>> On the point of transmission losses, they would not be lower for a
>> de-centralized scheme. By its very nature, a decentralized scheme would
>> have more transmission lines, not less.
>
> True, but each unit of energy might have to travel, on average, less
> far before being converted into work, Thus, if the typical
> transmission distance is under 50 km, losses in transmission are going
> to be less that if it's three or four times that. As I understand it,
> the need to avoid brownouts at the end of the line means having more
> power at the source than those near to the source actually need.
----------
Actually the losses on local lines will be as high or higher per MW-mile
than on major (and longer) transmission lines.
----------------------
>
>> And line losses are function of
>> power carried and distance traveled. While an individual line in a
>> de-centralized scheme would be carrying less power, there would be more
>> of
>> them. With centralized, you have one (or a few) large lines carrying
>> some
>> large amount of power (say 8GW) from point 'A' to point 'B' with losses
>> 'X'.
>> With de-centralized you have a whole network mesh of smaller lines, each
>> carrying some smaller amount of power from points 'C' through 'M' with
>> losses 'c' through 'm'. But the load (8GW) is still the same and the
>> average distance from generating unit to load is probably higher so
>> losses
>> are *not* less, if anything they would be more.
>>
>
> I don't see that. If C -- > M involves typically navigating less
> copper than A -- B surely it's the better option. If every significant
> source of demand has a generating unit nearby, with the surplus sent
> into the grid to the next closests point where there's unmet demand
> then surely losses are lower.
-------
No. You are comparing low voltage distribution lines to major high voltage
lines and for transferring larger amounts of power- the HV lines win out in
both efficiency and in reliability.
Yes you could, in theory, have a decentralised system and have all
generation near the load centers- but that presents problems. This was
done in the past but experience showed that the grid had and still has
advantages in terms of economics as well as reliability and stability. Part
of the problem is that most load centers require more (in terms of quantity
and reliability of supply) energy than local sources can provide.
------------------
>
>>
>>
>> >> Transferring a couple of GW of power over a couple hundred miles from
>> >> each
>> >> point of the compass is *not* for the faint at heart.
>>
>> > But still very doable. It's done all the time in NSW.
>>
>> Really? Where is this 'couple of GW' line that covers such a distance?
>
> I'll have to get back to you on NSW, but I note that the Chinese are
> planning to send 18.6 GW about 2000 km from the Xi,loda Xiangjiabo
> power plant. The Benmore Dam in NZ carries 1.2 GW over 500 km. Then
> there's that HDC line carrying 3.1 GW 1300 km down the Pacific Coast
> from Oregon to California.
>
> Using HVDC is obviously the way to go, particularly under water where
> capacitance is high. Basslink uses a submarine cable under Bass Strait
> (separating the Australian mainland from Tasmania) nearly 300km long.
> Admittedly, it's only carrying half a GW from Loy Yang in Victoria,
> but plainly, there's no technical reason why one could not build a
> more powerful link, or series of links.
----------
HVDC is great for transferring a great deal of power for a long distance or
for longer underwater cables. For shorter distances -particularly overhead,
it is more expensive than AC. It is necessary to convert from AC to DC-
transmit-then convert back to AC. They act as the backbone of a grid. There
are more examples available. Check out Manitoba Hydro,Quebec Hydro and BC
Hydro have large sources in the back country and interconnect these
sources in order to supply the high voltage systems AC and DC for
transmission to the remote load centers-( about the distance from Sydney to
Alice Springs). However DC is useless for collecting or distributing
energy so it is not a factor of consideration for your schemes.
Transferring 2GW for 200 miles over 500kv lines (more than one) is feasible
for point to point transfer provided sufficient sectionalisation and
compensation is provided but still point to point bulk transmission as are
the schemes that you and I have mentioned.
Gathering from small sources "each point of the compass" is another matter.
For what you propose- don't even think HV- AC or DC.
Daestrom has presented some good points- based on knowledge of limitations
and operation of utilities. I am not questioning your ability to think- you
have shown that- and I commend you on that but what is your technical
background, if I may be so impolite as to ask?
--
Don Kelly dh...@shawcross.ca
remove the X to answer
----------------------------
>
Vaughn Simon
"Don Kelly" <dh...@shaw.ca> wrote in message
news:MBvri.18934$rX4.12311@pd7urf2no...
Snip Don, snip. I have no idea what pearls of wisdom you wrote because I
wasn't willing to scroll down through hundreds of lines of text to hunt for
them. Please folks, think of your public.
Vaughn
Solar Flare
"Vaughn Simon" <vaughnsimo...@att.FAKE.net> wrote in message
news:C%Dri.384691$p47.3...@bgtnsc04-news.ops.worldnet.att.net...
daestrom
And more easily secured :-)
>> But many large-scale blackouts in the past were not caused by a loss of a
>> 'large' generating unit (at least not initially). The initiating event
>> for
>> the August 2003 blackout for example was caused by a transmission line
>> issue. If a large number of 'small' generating units are interconnected
>> by
>> transmission lines that are just as unreliable as before, then the
>> chances
>> of a major blackout are probably about the same.
>>
>
> That's true, but the effect of those transmission failures on the
> system as a whole will be smaller.
>
Not if the network is designed to operate near its optimal loading.
Overloading a 10 MW line is just as likely to cause a failure as overloading
a 800 MW line. And as Don pointed out, a 10 MW line may be more prone to
failure just because it is a low voltage line built to lower reliability
standards.
>> When it comes to 'stability' a large number of independent generating
>> units,
>> strong together over several hundred square miles with transmission
>> systems
>> is very difficult to keep stable. Power flow over a dense network of
>> inter-connecting lines means that power from each generating unit has
>> multiple pathways to reach the various loads. Controlling just how much
>> power flows over each line (to avoid overloading any given line) is
>> complicated now. Increasing the number of generating units and
>> transmission
>> pathways by a an order of magnitude will not make power flow, voltage and
>> frequency *more* stable. If anything, it will be less stable.
>>
>
> Again, it depends on a whole range of factors. Localised demand
> management is a pretty important tool, since a lot of power usage is
> potentially elastic -- one can choose when to pump water to catchments
> and when to stop. Water heaters can be adjusted to take advantage of
> times when demand is low, realtive to supply.
>
True, but outside the scope of this discussion.
>> On the point of transmission losses, they would not be lower for a
>> de-centralized scheme. By its very nature, a decentralized scheme would
>> have more transmission lines, not less.
>
> True, but each unit of energy might have to travel, on average, less
> far before being converted into work, Thus, if the typical
> transmission distance is under 50 km, losses in transmission are going
> to be less that if it's three or four times that. As I understand it,
> the need to avoid brownouts at the end of the line means having more
> power at the source than those near to the source actually need.
It is much more likely that the 'average' unit of energy would have to
travel *further*, not less.
One approach would be to group a large number of small generating units
around some central transmission station where their individual outputs
would be combined for transmission over some major line to the load (a major
city). The 'spurs' of such a spoke-wheel system would represent an
additional line whereas the traditional system would just locate the large
generating unit at the center of such a collection and transmit directly on
the major line. The 'spurs' increase losses and reduce transmission
reliability (even if net generation reliability is constant).
Or you might imagine a circular net arranged around the load itself. The
lines near the central load would be larger than the lines around the
periphery, but they would be carrying a larger load since power from the
peripheral units would combine with the power from units near the central
core as the power flowed towards the center. But think about this a bit, if
you spread the small generating units evenly over the land area, more of the
units would be near the periphery than near the center (land area rises with
distance from central load, for a circle, dA/dr = 2*pi*r). So the 'average'
distance that power must traverse is not exactly 1/2 the radius, but further
out then that. Further out means 'average' distance that a unit of energy
travels is higher, not lower.
Further distance traveled for an 'average' unit of energy means more losses
and more susceptibility to line failure (i.e. lower reliability).
Of course if the distribution is such that you cram the units together close
to the load and spread them out as you get further from the load, you could
mitigate this. Taken to the limit, you end up with all the generation right
on top of the load (i.e. a centralized plant right in downtown). Of course
there are practical limits to this and you end up with some 'acceptable'
distance from the load where you try and crowd all the generation into as
small an area as possible. Ooops, we're right back to centralized
generation.
daestrom
Fran
<snip>>
> >> A large number of small generating units may seem more 'reliable' since
> >> any
> >> single generating unit failure is less likely to cause an overload and
> >> collapse. That's the theory. But the details are crucial. If you swap
> >> one
> >> large generating unit that is more than 95% reliable with ten units that
> >> are
> >> only 85% reliable, have you really improved?
>
> > That's the key question though. There's no reason to assume that
> > smaller units will be less reliable than larger units. Depending on
> > how they are maintained, it might be that smaller units are looked
> > after better, or it might not.
>
> ----
> There is a good reason to assume that they will be less reliable-
> experience.
> -----------
>
It depends on how they are maintained, and by whom.
> >> Current technology requires
> >> that the system 'survive' a loss of the largest generating unit. Since
> >> generating units are somewhat centralized and large, this means there
> >> must
> >> be sufficient 'spinning reserve' to absorb the transient of losing such
> >> large units. If there were no 'large' units and a larger number of
> >> 'small'
> >> units were used, then yes the transient of losing a small unit is less
> >> severe and easier to compensate.
>
> ---------------
> Questionable. As small units will be tied through lower voltage lines- one
> doesn't feed a 500KV line from a 10MW unit. These lead to gathering points
> and retransmission at a higher voltage. Unfortunately the lower voltage
> lines are much more vulnerable than the higher voltage lines and the outage
> rate will rise.
Why so?
> Most outages that you observe are due to outages on the
> subtransmission system, not due to the major transmission system or large
> generators. Note also that small wind and solar sources will also need
> backup.
They will, but not as much as some assume.
> --------
> However the probability of loss of supply in terms of MWH /year may
> increase.
> Possibly I should redirect you to an old friend who speciality is power
> system reliability rather than just say nay (with somewhat more reason than
> you have to say yea).
> http://books.google.ca/books?id=IJBCJt2jaBQC&dq=power+system+reliabil...
I will check this out
>
> > Exactly. And remember, a large unit is a much better target for attack
> > from criminals than a small unit.
>
> ------
> Not necessarily so. Depends on the stupidity or lack of it that the
> criminals show.
> -----------
Really, there's very little point in putting something out of action
that causes minor inconvenience. One might as well be hung for a sheep
as hung for a lamb.
>
> >> But many large-scale blackouts in the past were not caused by a loss of a
> >> 'large' generating unit (at least not initially). The initiating event
> >> for
> >> the August 2003 blackout for example was caused by a transmission line
> >> issue. If a large number of 'small' generating units are interconnected
> >> by
> >> transmission lines that are just as unreliable as before, then the
> >> chances
> >> of a major blackout are probably about the same.
>
> > That's true, but the effect of those transmission failures on the
> > system as a whole will be smaller.
>
> ---------
> Not necessarily. Sometimes a small disturbance can have wide reaching
> consequences. See the NE blackout of 1964(? year is from memory).
> ------
>
Is 1964 a very relevant comparison? That was more than 40 years ago.
>
>
> >> When it comes to 'stability' a large number of independent generating
> >> units,
> >> strong together over several hundred square miles with transmission
> >> systems
> >> is very difficult to keep stable. Power flow over a dense network of
> >> inter-connecting lines means that power from each generating unit has
> >> multiple pathways to reach the various loads. Controlling just how much
> >> power flows over each line (to avoid overloading any given line) is
> >> complicated now. Increasing the number of generating units and
> >> transmission
> >> pathways by a an order of magnitude will not make power flow, voltage and
> >> frequency *more* stable. If anything, it will be less stable.
>
> > Again, it depends on a whole range of factors. Localised demand
> > management is a pretty important tool, since a lot of power usage is
> > potentially elastic -- one can choose when to pump water to catchments
> > and when to stop. Water heaters can be adjusted to take advantage of
> > times when demand is low, relative to supply.
>
> ------------
> This is not what is meant by power system stability- you are talking about
> peak shaving.
> ---------------------------
>
What I had in mind was allocating intermittent sources of power to
loads that could tolerate intermittency, and using the surplus to
supply other uses. That way, by 'shaving' you could maintain the same
output while pulling load out of the system.
> >> On the point of transmission losses, they would not be lower for a
> >> de-centralized scheme. By its very nature, a decentralized scheme would
> >> have more transmission lines, not less.
>
> > True, but each unit of energy might have to travel, on average, less
> > far before being converted into work, Thus, if the typical
> > transmission distance is under 50 km, losses in transmission are going
> > to be less that if it's three or four times that. As I understand it,
> > the need to avoid brownouts at the end of the line means having more
> > power at the source than those near to the source actually need.
>
> ----------
> Actually the losses on local lines will be as high or higher per MW-mile
> than on major (and longer) transmission lines.
> ----------------------
>
Is that merely a function of the voltage?
That may reflect the relative paucity of power supply options years
ago. Waste biomass is still radically underutilised.
It's not impolite. I've no technical background in electricity
generation/transmission. I'm just someone who, about 2-3 years ago,
became very interested in renewables, and began using much of my
limited non-work and non-family time to find out as much as I could
about each. I learn something new every day, which is great.
My principal concerns start from considerations of equity,
sustainability and ubiquity. What I'm keen to establish is how best to
match energy supply to human needs in ways that are sustainable and
equitable. I found the Japanese example interesting, because there
doesn't seem to be any really good solution for them. The nuclear
option is inherently going to be very expensive to make safe and
reliable and yet they don't have a lot of land to do biomass or wind
either. Wave/tidal is certainly a possibility, but in the end they
probably are going to have to import most of their energy, one way or
another or take bigger risks and accept bigger costs with nuclear.
Fran
Don Kelly
"Fran" <Fran...@gmail.com> wrote in message
news:1186468070.3...@j4g2000prf.googlegroups.com...
> On Jul 31, 10:44 am, "Don Kelly" <d...@shaw.ca> wrote:
> <snip>>
>
>> >> A large number of small generating units may seem more 'reliable'
>> >> since
>> >> any
>> >> single generating unit failure is less likely to cause an overload and
>> >> collapse. That's the theory. But the details are crucial. If you
>> >> swap
>> >> one
>> >> large generating unit that is more than 95% reliable with ten units
>> >> that
>> >> are
>> >> only 85% reliable, have you really improved?
>>
>> > That's the key question though. There's no reason to assume that
>> > smaller units will be less reliable than larger units. Depending on
>> > how they are maintained, it might be that smaller units are looked
>> > after better, or it might not.
>>
>> ----
>> There is a good reason to assume that they will be less reliable-
>> experience.
>> -----------
>>
>
> It depends on how they are maintained, and by whom.
--------
That is one factor- but, independent of this factor, what I said is still a
fact of life. You will find that large units, simply because of the cost of
failure, will be designed to be more reliable (and efficient) than small
units -this is not necessarily economic for small units.
---------
>
>> >> Current technology requires
>> >> that the system 'survive' a loss of the largest generating unit.
>> >> Since
>> >> generating units are somewhat centralized and large, this means there
>> >> must
>> >> be sufficient 'spinning reserve' to absorb the transient of losing
>> >> such
>> >> large units. If there were no 'large' units and a larger number of
>> >> 'small'
>> >> units were used, then yes the transient of losing a small unit is less
>> >> severe and easier to compensate.
>>
>> ---------------
>> Questionable. As small units will be tied through lower voltage lines-
>> one
>> doesn't feed a 500KV line from a 10MW unit. These lead to gathering
>> points
>> and retransmission at a higher voltage. Unfortunately the lower voltage
>> lines are much more vulnerable than the higher voltage lines and the
>> outage
>> rate will rise.
>
> Why so?
------
Go outside and look at a few lines. You should be able to see the difference
in physical construction- there are also other differences in terms of
protective measures. -----------------
>
>> Most outages that you observe are due to outages on the
>> subtransmission system, not due to the major transmission system or large
>> generators. Note also that small wind and solar sources will also need
>> backup.
>
> They will, but not as much as some assume.
The assumptions that are commonly made are based on experience. What is the
basis for your assumptions?
>
>> --------
>> However the probability of loss of supply in terms of MWH /year may
>> increase.
>> Possibly I should redirect you to an old friend who speciality is power
>> system reliability rather than just say nay (with somewhat more reason
>> than
>> you have to say yea).
>
>
>> http://books.google.ca/books?id=IJBCJt2jaBQC&dq=power+system+reliabil...
>
> I will check this out
>
>>
>> > Exactly. And remember, a large unit is a much better target for attack
>> > from criminals than a small unit.
>>
>> ------
>> Not necessarily so. Depends on the stupidity or lack of it that the
>> criminals show.
>> -----------
>
> Really, there's very little point in putting something out of action
> that causes minor inconvenience. One might as well be hung for a sheep
> as hung for a lamb.
------
You are not thinking. Think remote. Think unguarded -multiple easy low risk
targets.
--------
In other words you are isolating some loads and sources and actually
reducing the reliability of supply to these customers who can tolerate it.
while not improving it for others. If there is a grid then one cannot
independently direct energy from source a to load b. You could reduce system
peaks by simply disconnecting specified loads at certain times. That can be
done, and is, in many cases.
>> >> On the point of transmission losses, they would not be lower for a
>> >> de-centralized scheme. By its very nature, a decentralized scheme
>> >> would
>> >> have more transmission lines, not less.
>>
>> > True, but each unit of energy might have to travel, on average, less
>> > far before being converted into work, Thus, if the typical
>> > transmission distance is under 50 km, losses in transmission are going
>> > to be less that if it's three or four times that. As I understand it,
>> > the need to avoid brownouts at the end of the line means having more
>> > power at the source than those near to the source actually need.
>>
>> ----------
>> Actually the losses on local lines will be as high or higher per MW-mile
>> than on major (and longer) transmission lines.
>> ----------------------
>>
>
> Is that merely a function of the voltage?
Mainly -but also the design of the conductor system (Note that copper wires
haven't been used for decades- Aluminum Conductor-steel reinforced is the
common conductor and the choice of one or more per phase (as well as
individual conductor size) is dependent on both electrical and mechanical
considerations- in which resistance becomes a relatively minor factor).
-------------
No- years ago, it was common to have thermal plants in urban areas-less
common now. Objections to such central plants apply to biomass thermal
plants as well.
----------
You are asking good questions but the answers and the reasons are in some
cases fairly technical. In that way, you are looking at utopian solutions to
a problem where there is no "ideal" solution -only various "best" solutions
where "best" is determined by the chosen weighting of factors.
-------
>
> My principal concerns start from considerations of equity,
> sustainability and ubiquity. What I'm keen to establish is how best to
> match energy supply to human needs in ways that are sustainable and
> equitable. I found the Japanese example interesting, because there
> doesn't seem to be any really good solution for them. The nuclear
> option is inherently going to be very expensive to make safe and
> reliable and yet they don't have a lot of land to do biomass or wind
> either. Wave/tidal is certainly a possibility, but in the end they
> probably are going to have to import most of their energy, one way or
> another or take bigger risks and accept bigger costs with nuclear.
---
Some question as to the relative risks and costs. It is interesting to note
that Japan, of all nations, has nuclear power- could it be that was a "best"
choice based on their choice of weighting of various factors? Would it be
mine? I don't know as I don't have all the facts and data that the planners
had available. Would I object to nuclear where I live- no. It makes more
sense than some of the ideas being touted (including some "green"
alternatives).
--
Don Kelly dh...@shawcross.ca
remove the X to answer
----------------------------
>
> Fran
>
daestrom
>> ---------
>> Not necessarily. Sometimes a small disturbance can have wide reaching
>> consequences. See the NE blackout of 1964(? year is from memory).
>> ------
>>
>
> Is 1964 a very relevant comparison? That was more than 40 years ago.
>
Similar widespread blackouts also occurred in later years. One sometime in
the '80's (I can't recall exactly) and another on August 14, 2003. The root
cause of the 2003 blackout was a failure to trim trees along the power line.
This is something that could be even more widespread if the number of
transmission lines were raised an order of magnitude.
http://en.wikipedia.org/wiki/2003_North_America_blackout
Later that same year, Italy suffered a wide spread blackout, suggesting it
isn't limited to just the North American power grid.
daestrom