Vision: Ultra-small nuclear reactors, which will operate for 30 years without the need for refueling or maintenance and will save the emission of toxic diesel fumes, will provide heat and electricity to small towns in America
By Don Stover
The Toshiba company, best known as a manufacturer of entertainment electronics, now offers the smallest nuclear reactors in the world. The height of the reactor, known as 4S [acronym for Super Safe, Small and Simple], is about two meters and will be sealed in a concrete vault at a depth of about thirty meters underground. The reactor is also called a "nuclear battery" because it operates for 30 years without the need for refueling.
The secret behind the proposed reactor's ability to operate without the need for maintenance lies in its cooling system. In most of the nuclear reactors that operate in the USA, pressurized water is used, but in the 4S reactor, molten sodium is used as a coolant. Since sodium is a metal, it can be spun in the reactor with the help of electromagnetic pumps - saving moving parts that need repairs.
obstacles
Of the more than 400 full-size nuclear reactors operating worldwide, only two are currently cooled with sodium. One of the concerns is that if the sodium comes in contact with water, an explosion will occur. Another question is whether it will be possible to operate the reactor safely for 30 years without the need for inspections or repairs. If maintenance is still required, the reactor will have to be taken out of the ground and sent to a factory in Japan.
Expected
Toshiba hopes to install the first 4S reactor in Galena, Alaska [population 700] in 2012. Today, the residents of the remote town pay 45 cents per kilowatt for electricity generated from diesel. The electricity produced in the 4S reactor should cost half of this amount.
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In fact, silicone is a very cheap material! The reduction is the one that allows increasing the speed and efficiency of the processor, as the distance between the processor bodies is smaller, less energy and less time is needed to communicate between the parts.
A large processor with the same architecture would never achieve the quality signal of speed and efficiency
I remember that a year ago, maybe less, I read an article about a development by IBM, that they developed an adhesive that conducts heat much better, so that you can glue the fins (heat sinks) and make it conduct better.
In addition, there are cooling systems that are based on water, which cool better.
And if not, you can always throw the processor into a glass with liquid nitrogen and the cooling problems are solved...
Regarding the heat transition and the development of new methods, there are generally three mechanisms of heat transitions:
Conduction like between two solids (between the processor and the fins), convection through a fluid (between the fins and the air) and radiation (which is at really high temps, so not relevant).
The transfer of heat by conduction depends on two things: the surface area between the two materials and their coefficients of transfer of heat by conduction.
In the past, the heat in convection mainly depends on the convection coefficient, this coefficient takes into account, among other things, the geometry of the heat passage, say we use cylindrical fins, i.e. round columns. If we arrange them on a chessboard, we can put a flipper on any square (black and white) or on a certain color (only black). Between the two cases there will be a difference in the heat transfer coefficient.
Therefore, to solve the problem, you can search in three areas: the first is new materials with better thermal conduction, the second is to look for new configurations to arrange the fins and their shape, and the third is to switch to biological computers or any other technology that does not emit so much heat...
1. The computer's case plays a very important role in cooling, it is worth investing in a high-quality aluminum case (allows for more efficient heat dissipation) with a wide body and two 120 mm fans, one that draws air from the front and the other that emits hot air from the back.
2. It is also worth checking the possibility of water cooling for the computer (closed system of course) there are many computer stores where you can get such equipment and cooling with water is considered significantly better than air cooling, and here too you should invest in something of quality and not a toy.
Good luck, David Ben-Gurion would be proud of you (The Negev Flower)
You're right, and there's nothing you can do about it (except living in the Pole without a fan or in Tonga without a computer...)
A fan makes noise and it's annoying.
Ami,
There are more serious CPU fans that you can install in your computer and prevent it from crashing as a result of the CPU heating up.
Try to inquire with your computer guy, and if you don't succeed, I'll give you a name that can help you.
There is indeed a problem with the heat dissipation of processors and it stems from the density of the circuits (the tiny size) and the switching speed (the speed of the processor).
interesting. Thanks.
It seems that the cooling field needs to undergo a technological transformation because it is very basic to all processes. My computer shuts down from time to time (I live in the Negev today) and this is as a result of heat. The cooling fins of the processor are not doing a good enough job. It is a semi-passive cooler, since a ventilator is installed on these ribs that circulates the air over them to take the heat from them. The semi-passivity is in the relatively slow heat transfer from the processor to the ribs.
I sometimes think that today in a world where everything is miniaturized, we actually create small ovens and thus miss quite a bit of their efficiency. What would happen if instead of my small processor of only a few centimeters, I had the same processor with the same computing power, on a large board and parallel to the entire motherboard? It would take up space, but the passive cooling would be much more efficient. And what do I care if Will another board be placed inside this box?
I assume that there is also the problem of an expensive material (silicon) which is difficult to slice very, very thinly in order to expand the surface area for the needs of heat emission, while maintaining the efficiency of the calculation.
The article is interesting and enlightening.
Shabbat Shalom to all,
Ami Bachar
To Ami Bachar
The reactor cannot be completely sealed because it has to emit the heat. The cooling piping of the liquid sodium must, therefore, be outside the concrete shell or inside the concrete but close to the outer surface area. In cold areas, as reported in the article - in Alaska for example, it will probably be possible to be satisfied with air cooling, however, in warmer areas it is not possible to be satisfied with air cooling and water cooling will be necessary.
The sodium and water thing sounds a bit silly to me. Sealing something for thirty years is not such a complicated story. The outer capsule of the facility will be wrapped in a very thick layer of concrete and this can be surrounded by a layer of plastic. There is no danger that the sky will penetrate such a thing in the next million years, there will also be an earthquake there. Second, the cooling technology must be improved and promoted precisely in order to learn how to avoid the need to use water. We also remember that in facilities that are cooled by water, the same water goes out into the sea and pollutes it with heat! This heat does dissipate, but it is still dirty. Light is also a pollutant, by the way (for example, the lamps on the boardwalks of various kinds have a severe effect on the very high mortality of sea turtles that hatch and run to the boardwalk instead of the moonlight that is reflected from the sea).
Atomic energy sounds like a green energy option to me.