Atomic plants are built by engineers which know way more than I do....
In earthquake prone nations and by the Pacific oceans why in the world
would they build an Atomic plant almost at sea level???
I realize that it would cost a bundle to build a pad up about 150 ft. with
a sloping concrete wall facing the ocean.
This way some of the safety features maybe would not fail.
Wouldn't that be more cost effective (accountants) than what's going on
now???
They pump water around it to keep it cool so it was a 'cost saving' attempt technically I think.... I cant remember the full 'fact' but it had something to do with pumping sea water around the plant however I picked this up from a random news report so this is dubious fact :lol....
We have several Nuclear Power Plants in California, that are right on the coast, and both within the region considered part of the San Andreas Fault Zone.
I think the concept is that the nuclear fuel heats water (pressurized) that in turn powers huge turbines that generate electricity for the grid. Being right on the ocean means that they can then dump the water that has been heated (but, is not radioactive) directly into the ocean. Also, seawater can be used conveniently for cooling. We had lots of protests here from concerned citizens over the proximity to the San Andreas Fault of both the San Onofre (http://en.wikipedia.org/wiki/San_Onofre_Nuclear_Generating_Station), and Diablo Canyon (http://en.wikipedia.org/wiki/Diablo_Canyon_Power_Plant) Nuclear Power Plants, and, they engineered them to withstand whatever earthquake magnitude was considered probable.
Agreed.
But not tidal waves caused by an offshore earthquake.
Unlike many parts of the world, we have a tsunami warning system that will provide advance notice that a tsunami is coming.
Quote from: MichaelW on April 13, 2011, 01:12:16 AM
Unlike many parts of the world, we have a tsunami warning system that will provide advance notice that a tsunami is coming.
(http://trendsupdates.com/wp-content/uploads/2009/08/AsteroidImpact.jpg)
Power plants, whether using nuclear or fossil fuel, require a lot of cold water to condense the steam as it exits the electricity producing turbines. The condensed steam is then recovered as pure water and recycled to the reactor (or furnace) to generate steam again. (In nuclear power plants, that pure water may be radioactive.)
The heated cooling water is generally sent to cooling towers where it is contacted by a flow of air and cooled by evaporation. That is creating the plume you see coming out of those cooling towers when the water vapor gets in contact with the colder air at the exit. (In nuclear plants, that cooling water is never exposed to the nuclear fuel rods and is thus not radioactive.)
In the process, the salts in the cooling water get concentrated and part of it must thus be disposed off continuously and replaced with fresh water to prevent overconcentration of those salts. Thus the need for a large supply of water and also a place to dispose of the concentrated cooling water. Oceanside is thus an ideal place.
Hydroelectric power plants also need a very large supply of water but for a completely different reason. :8)
there is also a need for "heavy water" used to stabilize and control the nuclear reaction
heavy water is made up of water molecules with hydrogen atoms that are an isotope
a normal hydrogen atom has a proton and no neutron
the isotope "deuterium" has a proton and a neutron
heavy water may be found in ordinary every-day water
something like 1 in 6000 molecules of regular water is "heavy"
they can isolate the heavy water molecules by electrolysis (repeatedly)
but, it is mighty handy to have a large supply of water on hand to get the 1 in 6000 molecules :bg
Hi,
Power plants also tend to be close by the users of the power
as long distance transmission is costly in terms of both money
and efficiency. So if a lot of people live on or near a fault, you
can expect their power plants to be there as well. Newer kinds
of technology is improving things though.
As a side note, a PBS show on Niagara Falls noted that the
first power plant there was built by Tesla and most people
did not think it could power a city 30 miles away. But it did
due to alternating current and a relatively high voltage for the
time.
Cheers,
Steve N.
Quote from: FORTRANS on April 13, 2011, 12:06:18 PM
Hi,
Power plants also tend to be close by the users of the power
as long distance transmission is costly in terms of both money
and efficiency.
A pity that Tesla is not alive today. Im sure he would have found an efficient way of doing it.
Hindsight is always 20/20 and I'm sure those engineers did contemplate many factors before and during construction, but unlike software engineering you can't easily go back and tweak something below the foundation with compromising the rest. So of all the combination and permutations, one must resort to reasonable probabilities. Most have lifestyles that are completely dependent upon amenities such as power and natural gas. Where I live and as we had -40C weather for almost 3 weeks last winter, if the power was to go out for 3 or 4 days, catastrophe would ensue. The point is and due to cost considerations 1:8000 people here would be suitably equipped, the rest would have experience major damage as all their plumbing would have froze. The reality is in my 60 yrs of existence, I've only experienced one 9 hr power outage in winter and it wasn't that cold. This complacency is what makes us compromise for the sake of saving money and that exact dynamic exists ubiquitously it seems.
yah - and.....
it's Japan - not like they have billions of acres to pick from
Quote from: xanatose on April 14, 2011, 12:44:31 AM
A pity that Tesla is not alive today. I'm sure he would have found an efficient way of doing it.
Hi,
Actually, efficient methods methods for long distance transmission
exist. However they are expensive and somewhat complex. If
they were cheaper, large scale solar power and wind power would
be much more practical than they are currently.
Tesla actually had a plan for distribution of electricity via his
famous "coil" or generator. It was a bit "outside the box" and
at the time, completely impractical. From some odd commentary
on TV shows, it seems that some of the current "out of the box"
'characters' would like another go at trying his idea out. Seems
very unlikely to be a viable idea to me. Not to mention _very_
expensive to try it out if one even wanted to. But still an amusing,
interesting, and creative concept that was (and still is? he he)
ahead of its time.
Cheers,
Steve N.
i will agree that it was a creative idea
beyond that, it has little merit because it is extremely inefficient
the field strength at a given point is inversely proportional to the square of the distance :bg
as for transfering energy over great distance...
what do you guys think those high-tension lines are ?
they are very high voltage transmission lines
by "transmission lines", i mean they are carefully designed to be efficient
they are viewed mathimatically as a series of "lumped elements" of inductance and capacitance
and, using a higher voltage means a lower current for an equivalent power level
a lower current means a lower IR drop - lower loss
Hi Dave,
Yes, inefficient. However I think he thought that the field
would follow the the crust of the Earth, not sure why, which
would lower the losses somewhat. Still horrible in my estimation.
I was using "out of the box" as a euphemism.
The current high tension lines do exist and do work. There
was an article in the November 2010 Scientific American that is
titled "How to Build the Supergrid" that points out some require-
ments for upgrading our (North American/USA) electrical
transmission grid. The author is concerned with losses using the
older lines and building new lines with older technology and
advocates using new lines using newer technology to do the upgrade.
Gains in efficiency seen to require still higher voltages and DC currents.
An interesting read if your library carries the magazine. An
expensive infrastructure upgrade that will have to done in any
event sooner or later. Pity that the Republicans dislike building
infrastructure and baulk. Pity the Democrates can't think ahead.
Delaying things just increases the total cost.
Cheers,
Steve N.
yah - they are too busy spending money on an unneeded underpass in Boston
but, hey, at least the rich-ass contractors that paid off the politicians are making out
personally, i think a larger number of smaller generators would be a good start
we need to be using solar and geo-thermal energy
wind and other sources are nice, too - but solar and geo-thermal have an added advantage
they help to reduce the global temperature :U
Tesla wanted to make energy avaiable to everyone. He foresaw the problem with nonrenewable energy sources and out of control energy waste. The idea was to use the earth natural forces (hydro-electrical, thermo-electrical) and be able to send it huge distances by resonating the magnetic field of the earth. Problem is that the instalations need to be huge in order to cause the resonance effect on the earth magnetic field.
http://www.reformation.org/tesla-wireless-transmission.html
http://www.teslauniverse.com/nikola-tesla-patents-1,119,732-transmitting-electrical-energy
We are talking about a guy that was not only the father of modern technology, but also the creator of an earthquake machine based on resonance. He new first hand on the power of resonance. If you send the energy at the correct frequency, you could get the magnetic field to resonance, thus the energy send would increase (just like a sound wave that makes a material resonate).
I watched a history channel show on Tesla..He was the one that came up with AC current,is responsable for the electric moter among other things we take for granted. Edsion wanted only DC for power, and Edison "Stole" an invention from Tesla(Tesla worked for Edison,and was promised a large sum for inventing something for Edison) Edison screwed tesla for the money. Gives a different perspective about Edison. If you get a chance to view the History channel's show on Tesla, watch it. Tesla was a bit strange, and said he was in communacation with Alians. Tesla was WAY ahead of his time.
i am an engineer - you think i'd idolize Edison, right ?
nahhhhhh
he was an asshole thief - lol
more of a patent attorney than an inventor
to date, he still has more patents than anyone in history
but - that is because he was an expert at getting his name on someone else's work
i have FAR more respect for Archimedes, Newton, Franklin and of course, Einstein
I believe that Edison was a firm believer in sweat shops. And in taking his workers ideas and place patents upon them.
He was the equivalent of the modern day CEO. "Take credit of other peoples work. And make a ton on money while paying peanuts."
There is the situation in Tasmania that they have an excess of power and not enough industry t use it so they sell some of it to the mainland. Apparently they use a very high voltage DC line under Bass Straight to Victoria which appears to work OK, I don't claim to userstand why its done as high voltage DC but apparently there are technical gains in efficiency terms from doing so.
i'll come down there, only if i get to stay with Rachael Taylor :P
Quote from: hutch-- on April 27, 2011, 04:34:52 AM
There is the situation in Tasmania that they have an excess of power and not enough industry t use it so they sell some of it to the mainland. Apparently they use a very high voltage DC line under Bass Straight to Victoria which appears to work OK, I don't claim to userstand why its done as high voltage DC but apparently there are technical gains in efficiency terms from doing so.
Hi,
In the article I mentioned earlier, high voltage DC has lower
losses and better control than high voltage AC. A quote out of
context "...less than half the alternating-current losses at the
same voltage." They also allow power to be transferred from
one power grid to another without synchronizing problems
(phase and frequency). The required conversion to AC adds
some pluses and minuses of course.
Regards,
Steve N.
i don't think that is strictly true
however, i can see where DC might be very advantageous in an underwater environment
a lot of things come into play - transmission distance, wire used, voltage and current, of course
but the surrounding environment also makes a difference
when you say "high voltage", i have to ask "how high" - lol
comparing 10 kV DC to 10 kV AC is like comparing apples and oranges in many respects
in DC circuits, the loss is primarily due to simple wire resistance, assuming that the insulation is adequate
in AC circuits, calculating losses is somewhat complex
Hi Dave,
Quote from: dedndave on April 27, 2011, 02:39:45 PM
i don't think that is strictly true
?
Quote
however, i can see where DC might be very advantageous in an underwater environment
a lot of things come into play - transmission distance, wire used, voltage and current, of course
but the surrounding environment also makes a difference
when you say "high voltage", i have to ask "how high" - lol
comparing 10 kV DC to 10 kV AC is like comparing apples and oranges in many respects
Dang, you went and wanted context. And I wanted to limit
typing. "Muntz calculates that the same 100-mile line loaded
with the same 800 MW, but operating at 500 kV, would lose
3.82 MW, less than half the alternating-current losses at the
same voltage. Push the line up to 800kV,and losses drop to
1.5 MW, also less than half for a 765 kV alternating current line."
In his maps, the lowest voltage is "230-kV AC".
Quote
in DC circuits, the loss is primarily due to simple wire resistance, assuming that the insulation is adequate
in AC circuits, calculating losses is somewhat complex
Hm, he does have a, to me, strange comment. "... In
these cases, direct current was selected because it is efficient
and controllable. Alternating current follows the path of least
resistance, buzzing along random wires like water on a mountaintop
trickling down various streams to pool at the base. A direct-current
line is like a pipe from top to bottom, with a pump that can be
adjusted in real time." Simile for effect?
Anyway,
Steve
well - there is loss, then there is voltage drop
at any rate, i can't imagine what the heck you would do at the end of the wire with 500 kV DC - lol
there are no tubes or sold state devices that can switch that
with AC, you use a step-down transformer, which may be as good as, let's say 75% efficient, tops
anything you do the high-voltage DC is likely to be in the neighbourhood of ~50%
Quote from: dedndave on April 27, 2011, 04:55:59 PM
at any rate, i can't imagine what the heck you would do at the end of the wire with 500 kV DC - lol
there are no tubes or sold state devices that can switch that
with AC, you use a step-down transformer, which may be as good as, let's say 75% efficient, tops
anything you do the high-voltage DC is likely to be in the neighbourhood of ~50%
Hi Dave,
You should read the article. Rats, their site just has a
summary. It might make a big bug zapper?
"... That is because special converter stations are needed
at each end to change alternating current to direct current and
back again. The conversion requires massive electronics that
eat up about 1 percent of the electricity at each end. ..." The
photograph of one does have that massive look to it.
Regards,
Steve N.
i must be a crappy engineer - lol
the best DC to DC switcher i ever designed was about 80% effecient - 85% tops (under the right conditions)
i was damn proud of myself, too :P
fortunately, power distribution is not really my forte'
i usually design analog, digital, and RF circuits
in spite of the fact that i started out playing with radios, i would say RF is my weakest of the 3 :P
Let me see if I have this right, any transmission conductor (power line) has both capacitance and inductance which leads to a rise time with voltage change (I know this from electromagnets and DC brush motors where you have the hysteresis characteristics but that is also subject to the steel cores [ in transformers ] ).
Now I am guessing but high voltage DC does not have the sign inversion and thus voltage change so it misses out on the inductive and capacitive losses ?
it isn't a simple thing at all - lol
but, in AC circuits, a transimission line may be viewed as a series of "lumped elements"
(http://images-mediawiki-sites.thefullwiki.org/09/5/3/4/4376013540864935.png)
this image demonstrates an "unbalanced line"
for balanced transmission lines, there would also be inductive elements in the lower "arm"
impedance matching, standing waves, and a variety of other math fun comes into play
we usually use a smith chart to do the math for us :P
(http://www.submm.caltech.edu/cso/receivers/492trind.gif)
http://it327.groups.et.byu.net/images/Smith%20chart.jpg
this is a bit of a simplification, but easier to understand...
in a DC circuit, you will lose voltage due to resistance in the wire
the power lost is P = E x I, where E = voltage drop and I = load current
in an AC circuit, you lose both voltage and current together
now that i remember a little better, they originally chose AC current because
it was easier to distribute while maintaining nearly the same voltage
as voltage drop accumulates, they put a transformer in and everyone is happy again
but, there are other reasons also
AC is much more "natural" when it comes to converting mechanical energy (like Niagra Falls) into electrical energy
the rotating field windings in the generators want to put out the sinusoidal wave we are all familiar with
(http://www.casellausa.com/en/images/help/sine_waves.jpg)
far more efficient than a DC generator
Quote from: dedndave on April 29, 2011, 04:29:55 AM
AC is much more "natural" when it comes to converting mechanical energy (like Niagra Falls) into electrical energy
the rotating field windings in the generators want to put out the sinusoidal wave we are all familiar with
far more efficient than a DC generator
And since an alternator doesn't need a commutator and brushes to extract pieces of this sine wave and assemble them into something resembling DC, they are mechanically much simpler and more reliable. And for similar reasons, AC motors are generally much simpler and much more reliable than DC motors.
Had a quick read around and the rough distinction is that AC is far easier to deal with, adjust voltages and distribute but over very long distance transmissions DC beats it in far lower losses and less expensive cabling.
Some Siemens advertising, 800 Kv system in China.
http://www.youtube.com/watch?v=uLKfDjUfor4
http://www.energy.siemens.com/hq/en/power-transmission/hvdc/
yah - Siemens no doubt makes the switching devices - lol
they have made solid state power devices since i can remember, which lately, isn't very long :bg
I guess 800 kv semiconductors would really be something. I have seen 400 volt stuff for specialised audio but 800kv, ho ho ho.
i dunno what they do
but - i suppose you could cascade a number of devices to handle it
i can't imagine anything being 99% effecient
maybe they use the HV to shock a bunch of old guys that are peddling bicycle generators :lol
i hafta apply for a patent................
(http://img97.imageshack.us/img97/7933/hvconv.png)
Quote from: dedndave on May 02, 2011, 10:52:35 AM
i dunno what they do
but - i suppose you could cascade a number of devices to handle it
i can't imagine anything being 99% effecient
Hi,
Well some things are inherently efficient. Though rarely
when dealing with electricity. Maybe, like in "Catch-22", they
make it up in volume?
Oh well,
Steve N.
I read this somewhere and don't know if it's fact or fiction.
It was about putting hundreds of those 3-bladed windmills off the Atlantic coast. Actually they could go from New york
to Miami. They would generate DC current which would go to many AC converter stations I don't know how many
miles apart. This would let them take power from where the wind was blowing and bypass where it was not.
Sounds feasible but expensive.
Quote from: shankle on May 03, 2011, 12:12:27 PM
I read this somewhere and don't know if it's fact or fiction.
Hi,
It's a proposal. So neither fact nor fiction as yet.
Cheers,
Steve N.
Quote from: dedndave on May 02, 2011, 11:09:46 AM
i hafta apply for a patent................
(http://img97.imageshack.us/img97/7933/hvconv.png)
This reminds me of Tesla first invention, when he was 6. He invented using insects as an engine (well actually more a toy that moved things). Interesting the things you can do when you are bored.
very nice topic.
Only to mention another way of obtain energy. Using the waves of the sea.
(http://www.acionista.com.br/sustentabilidade/Ondas%20do%20Mar%20-%20conjunto%20de%20flutuadores%20-%20arte%20gr%C3%A1fica.gif)
i think geo-thermal is a good idea
get the energy we need - and cool the planet at the same time
i should get a nobel prize for such a nice green solution :U
(http://blogs.discovermagazine.com/cosmicvariance/files/uploads/nobel.jpg)