Submitted by Anonymous on Fri, 2013-08-30 08:02.

Once again the anti-nukes conclusively demonstrate that they are totally clueless about the technology. The above poster states:

Seems silly to superheat water(?°F) in order to simply boil it 212°F

The figure of the boiling point of water being 212°F is only true for water at atmospheric pressure
A BWR doesn’t operate at atmospheric pressure; it operates at a pressure of about 75 atmospheres or 1000 – 1100 psi. At those pressures, the boiling point of water is no longer 212°F but 550°F.
Perhaps the above poster can get a little education at:
http://en.wikipedia.org/wiki/Boiling_water_reactor

The cooling water is maintained at about 75 atm (7.6 MPa, 1000–1100 psi) so that it boils in the core at about 285 °C (550 °F)

Why is the process carried out at these elevated pressures and temperatures? Because it is more efficient than if it were carried out at atmospheric pressure. Contrary to the ill-conceived, and UNEDUCATED opinion of the above poster; it is NOT SILLY AT ALL!
The above poster also states:

Aren’t there significant inefficiencies involved there?

Welcome to the REAL WORLD and the Laws of Physics.
The anti-nukes and so-called “environmentalists” are always pointing to inefficiencies, and wondering why we have those inefficiencies.
The reason is that the Laws of Physics MANDATE those inefficiencies and provide NO WAY to get around them. The anti-nukes and so-called “environmentalists” don’t understand that the Laws of Physics put constraints on the transformation of energy, and limits the efficiency by which we can do certain processes.
More research isn’t going to “solve” the “problem”; these are limits that we have know for a long time. Scientists have known about these limits since the earliest steam engines or about the time our Founding Fathers were drafting the US Constitution. We haven’t found a way around them in over 2 centuries, and we know there is no way “around” these limits since they are physical laws.
One of the limiting laws is the 2nd Law of Thermodynamics, courtesy of the Physics Dept. at Georgia State University:
http://hyperphysics.phy-astr.gsu.edu/hbase/thermo/seclaw.html#c2
So many so-called “environmentalists” that I’ve conversed with want to dispense with “waste heat” as being unneccessary and want to do what is protrayed in the right half of the figure in the link above. They want to take ALL the energy in heat QH and turn it into useful work W.
Unfortunately, the Laws of Physics DON’T LET you do that!!
It says that would constitute a perfect heat engine which is FORBIDDEN by the 2nd Law.
If the so-called “environmentalists” are going to be listened to, they need to dispense with these childish notions of “perfectly efficient” machines, “grow-up”, and LEARN some Physics.
The Laws of Physics will ALWAYS limit what you can do.
We see that the 2nd Law of Thermodynamics limits how efficient we can make heat engines like the Rankine steam cycle engine associated with nuclear power plants.
However, even the “greenie” energy sources are limited too by the Laws of Physics. For example, “Betz’s Law” puts a limit on the efficiency of wind turbines that the “environmentalists” don’t know about:
http://en.wikipedia.org/wiki/Betz%27_law
Solar photovoltaic cells are limited by the “Quantum Efficiency”, “Charge Carrier Recombination”… and a host of other limits.
The Laws of Quantum Mechanics only allow a single photon of light to help boost an electron up and over, the “energy band gap” between the valence band to the conduction band, so that that electron can be part of the electricity produced in a solar cell. Unfortunately, not all the photons in sunlight are energetic enough to give the electron enough energy to get it into the conduction band, and the Laws of Quantum Mechanics don’t let multiple photons combine their energy to help a single electron. So we can NEVER extract all the solar energy in sunlight with solar cells. That’s the essence of the “Quantum Efficiency Limit”.
In a solar cell, you want the photons of sunlight to boost an electron to the conduction band ( leaving a “hole” ), and then you collect the electrons, run them external to the solar cell to power the load, and then return the electrons to the solar cell where they find one of the “holes”, and return to the valence band; hence maintaining the solar cell as electrically neutral.
However, a certain fraction of the electrons will find a “hole” before they power the load. They will emit a photon, and settle back into the “hole”. The energy of those electrons will NEVER find their way out to power the load.
So yes; there are inefficiencies in the Rankine steam cycle. A Rankine steam cycle will be, at most; 40% efficient.
The so-called “environmentalists” gasp at that figure.
However, solar cells are only about 20% efficient in practice, because of the concerns mentioned above.
Somehow, that doesn’t bother the so-called “environmentalists” as it does with the Rankine steam cycle.
The typical UNEDUCATED anti-nuke is so concerned for the 60-70% inefficiency of the Rankine steam cycle on a nuclear reactor, but they are not concerned at all about the 80% inefficiency and waste heat from solar cells.
Solar cells produce waste heat too – and don’t say that heat would have been there anyway. Solar cells are DARK for a reason; you don’t want to reflect sunlight, you want to absorb it.
So solar cells make the landscape “blacker”; they reduce the albedo, and hence the amount of sunlight that is reflected to space. If solar cells turned ALL the extra energy they absorbed into electricity that was sent somewhere else; they wouldn’t produce waste heat or thermal pollution. However, they don’t turn all the sunlight into electricity; only 20% or so. So the majority of the extra absorbed energy that is absorbed by the solar cell instead of being reflected to space, is turned into heat; and solar cells are thermal polluters. On a per unit of electricity generated; they are WORSE waste heat producers than Rankine steam engines.

Submitted by Anonymous on Sun, 2013-07-28 12:35.

There are many sources of clean energy! Geothermal, solar, wind, and water as well as energy emitted from the earth. If all of these are used and researchers put in enough time and willpower into it, all of these systems can be improved. Solar power is getting more advanced.
Nuclear power is dangerous, and extremely harmful to the environment and all it’s inhabitants. No matter what figures you compile to be “right” or what expert says so, there is always another expert who disagrees, it is dangerous! Many people have died in nuclear accidents, and what if Japan has another big earthquake? The food supply in the Pacific is already contaminated, fish are testing positive for radiation such as tuna that spawns off the coast of Japan. They are finding radioactive particles in the seaweed and kelp off of the California shore, there are at least 3 types of radioactive particles in the rain and air all over the US that have come from Japan. Our bodies can repair the damage as long it is low exposure that is not too prolonged but if we get a massive dose or ongoing low exposure our health is very much at risk. Putting the health of the entire earth at risk is just really stupid, no matter how passionate you are in arguing about it.

REALLY??

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Submitted by Anonymous on Fri, 2013-08-23 13:15.

When confronted by facts versus their warmed over leftist dogma; the anti-nuke flies off the handle.
The number of accidents at nuclear power plants pales compared to aviation accidents. We don’t shutdown aviation; and those accidents actually kill people.
At least in the nuclear accident, the “victims” have a slightly increased chance of getting a curable cancer decades from now.

Submitted by Anonymous on Fri, 2013-08-16 12:17.

🙂

Submitted by Anonymous on Mon, 2012-05-07 05:48.

Do you have some science to show what a 0.015% increase in exposure will do to rates of cancer?

Submitted by Anonymous on Thu, 2012-04-12 08:10.

The problem is how to distinguish between the real scholars, and the anti-nukes that are just out to scare you so they can get their way.
Certainly anything you see posted by BRAWM members can be trusted.
The other thing you can do is read what the real experts have to say. One of those experts was summoned by the US Congress to give testimony. So you can also believe what he says. Courtesy of the scientists at the Health Physics Society:
http://hps.org/documents/John_Boice_Testimony_13_May_2011.pdf

The health consequences for Japanese workers and public appear to be minor

The health consequences for United States citizens are negligible to nonexistent

Interesting seemingly false testimony

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The problem…

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So you can believe what he

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