In order to create nuclear fusion in the laboratory, one must find ways to bring the atoms closer together, in a way that makes it possible to overcome the repulsion between them. One method is using strong magnets, which will push the atoms together. Another method, which today seems more promising, uses lasers
Nuclear energy, not what you thought
There is no doubt that in the coming decades humans will have to make a significant change in everything related to our energy sources. The fossil fuels - coal, oil and natural gas - are depleting and going at an accelerated rate. Renewable energy sources - such as solar energy, wind and water cascades - are still very far from meeting the growing demand. In the foreseeable future, there is no doubt that the only source that will be able to provide the huge amounts of electricity that humanity requires is nuclear energy. The energy currently produced in nuclear bombs, and also in nuclear power plants, is obtained from nuclear fission - it is released when we break down the nucleus of a heavy atom, uranium or plutonium, into smaller nuclei. However, the same energy, and perhaps even more, can also be produced in the opposite process - fusion of nuclei of small atoms into one large nucleus. This process takes place permanently in the sun, where hydrogen atoms are fused to form helium nuclei. It also occurs in a hydrogen bomb, which releases much higher energy than a normal nuclear bomb.
give to get
The main problem with nuclear fusion, which requires very high temperature and pressure conditions to be maintained. Hydrogen nuclei consist of protons - heavy particles with a positive charge. When two such nuclei are brought together, the positive charges repel each other, and a lot of energy must be invested to overcome the repulsion. The heat and pressure in the core of the sun provide such energy, and in a hydrogen bomb the conditions are created thanks to an initial reaction of normal nuclear fission. But when this happens - we have no control over the fusion process of the hydrogen nuclei. One of the great challenges of science and technology today is to create a controlled process of nuclear fusion, which can be harnessed to produce electricity. The problem is that, until now, all attempts to produce energy in a process of controlled fusion required an energy investment far greater than the output obtained from the fusion itself. Now, the scientists are looking for ways to optimize the process, and make it worthwhile.
slow ignition
In order to create nuclear fusion in the laboratory, one must find ways to bring the atoms closer together, in a way that makes it possible to overcome the repulsion between them. One method is using strong magnets, which will push the atoms together. Another method, which today seems more promising, uses lasers. This method is led by the American National Ignition Facility (NIF). In the institute's facilities, 192 powerful laser beams are aimed at one tiny sphere, about one millimeter in diameter - containing hydrogen atoms. More precisely, it contains unique forms of hydrogen, known as datarium and tritium, whose nuclei are heavier than normal hydrogen (these are the hydrogen atoms from which heavy water is produced), and their repulsive force is smaller. When the lasers heat the ball to a very high temperature, pressure conditions are created inside it that allow the hydrogen nuclei to fuse into helium nuclei. The helium nuclei move at high speed near the spherical wall, and their energy can be "harvested" and converted into heat. However, even though the process takes place, the energy invested in lasers is much higher than the one ultimately obtained from nuclear fusion on such a scale.
small step
Recently, the NIF scientists reached an important achievement - even if very preliminary. For the first time, a higher energy was received in the process than the one that heated the pellet itself. With this, it should be noted that the output was considerably higher than that which reached the pellet, but still tens of times less than what was invested in the entire process. "For the first time, heating using alpha particles (helium nuclei) was demonstrated there," explains Prof. Aryeh Ziegler from the Hebrew University, whose progress was recently presented at a conference he organized in Jerusalem. "One day this process has a very high potential to reach a high energy yield. Its great advantage is the use of particles such as deuterium and tritium, which are very common, relatively cheap, and it does not appear that they are going to decay in the foreseeable future." The nuclear fusion process has several other great advantages over fission, and most importantly - it does not use rare materials such as uranium and plutonium, whose extraction and enrichment processes are very expensive, and it emits much less radioactive radiation, therefore it is very safe to use. However, even the most optimistic agree that it will take many years to perfect the process to such an extent that it will be energetically efficient, and economically viable. But even this long journey will consist of small steps, and at least one of them will be made in the last progress.
19 תגובות
Regarding a cold nuclear reactor.
Reading gives the false impression that a nuclear reactor can only be one of two types: a fission reactor or a fusion reactor. The situation is different: theoretically a nuclear reactor of the transmutaion type is possible.
A nuclear exchange process is an initiated process in which atomic nuclei undergo an isotope change (that is, neutrons are added to the original atom or neutrons are subtracted from the original atom). Each atomic nucleus has an energy value called binding energy. An isotopic change changes the binding energy, and if the binding energy decreases, then the excess binding energy can (at least in part) be energy that the reactor creates for use by those who operate it.
Andrea Rossi's i-cat cold nuclear reactor may operate through nuclear exchange. This area is still unclear. Most likely, long before it is clear what is happening in the E-Kat reactor, this reactor will be used. E-Kat miners are supposed to be sold to the public within a year or two, if there are no unexpected delays.
"The heat and pressure in the core of the sun provide such energy" - this is not true. The temperature and pressure in the center of the Sun are too low and fusion occurs thanks to the quantum tunneling effect. This is why the sun "burns slowly" and has lived for more than 10 billion years. In stars where the heat and pressure are high enough, the nuclear fusion process ends in only a few tens of millions of years.
Asaf
I'm not preventing you from expressing an opinion, I just argued that before deciding something in rulings to learn a little
on the field. Some of the news you confidently cite are misinformation and the basic claim
That the laser in NIF receives financial support because it has military applications is essentially unfounded.
We did plan to use lasers in the Star Wars project but it was for the purpose of interception
Spacecraft and satellites In any case the above project was shelved and the lasers at NIF have nothing to do with this issue. It
It is true that in Europe there is a competing Iter project, but I don't think it is possible to determine with certainty
And more without understanding in which field the project was preferred, but as mentioned, everyone is entitled to express their opinion
His opinion.
Guys, instead of fighting try to work together. Seal the kernels with a magnet and heat them with a laser, you will get great popcorn, melted and cold.
"And look at that, even though I'm neither a journalist nor a scientist. I allow myself to express my opinion" - has anyone here forbidden you to express your opinion? All in all, the person who said (who happens to understand physics more than you) said:
"Because of the problems, different projects are trying different methods and it should not be determined sharply and decisively that a certain method is better than another." And you don't agree with that. (And if you 'allow' me to express my opinion: you don't understand physics and are a bit of a jerk)
To Ehud, the Iter project has partners from all the leading countries in the world. The Americans withdrew and after they realized that they would be left behind, they returned to the project. And you can see from this, even though I am neither a journalist nor a scientist. I allow myself to express my opinion, apparently there is a democracy in Israel.
Lorem,
This means cold fusion which is performed at a low temperature (less than 001 degrees).
There is no objection to creating a device that will reach a high temperature within room temperature, and within this device the melting will take place, so that the heat that will be generated will be directed to the continuation of the process...
Asaf
Since, according to you, you are neither a journalist nor a scientist, I would not rush to make claims if I were you
Like "the laser method is only being tested in America, and has not yet had an impressive success. research
The laser is budgeted, because of a military application."
As I mentioned to you the attempts to generate energy by fusion are old and different ideas
Various problems were encountered, magnetic and hydrodynamic instabilities, inability to focus sufficiently
Point energy by lasers and instabilities. Because of the problems, different projects are trying methods
different and it should not be stated clearly and decisively that a certain method is better than another.
I don't remember who it was who was asked in the interview "When will humanity produce energy from fusion?"
But he is one of the leaders of the fusion project. That's how Hana answered, "When
This will be necessary." Today, given oil prices, the investment in fusion as an energy source
is not necessary. As soon as it becomes necessary for the existence of humanity, it will invest its resources
the necessary (and the huge money) and then it is likely that they will overcome the problems.
Regarding cold fusion, as we mentioned here, it is a fantasy and there is no need to continue to engage in it.
Cold fusion is a physical impossibility. About a little more than traveling at a speed exceeding the speed of light.
On the other hand, hot nuclear fusion is possible and has such advantages that it is impossible to understand the dragging of feet towards the development of this technology. I would expect from various governments around the world an effort along the lines of the "Manhattan Project" to develop the technology.
In relation to the French experiment (the operation with a laser mechanism). This is what was said on the H network (in the International Hour program, a few years ago). In any case, the use of lasers in military technology is discussed. In Ronald Reagan's "Star Wars". And it is known that China can dazzle satellites. So laser research will receive a military budget.
Since I am neither a journalist nor a scientist. These are popular science seekers. A Google search will show that all the details I wrote are reliable. The nuclear cut (there is no such thing as a cold cat). It is carried out in England in South Korea and much more. In South Korea they lowered the temperature to reduce the resistance of the magnets. In any case, the whole nuclear fusion initiative started in Russia, and today a huge project is underway in France to test the economic and technical capacity of this technology.
There is no doubt that cold nuclear fusion will be a revolution in all areas of humanity.
Interesting, how many budgets do governments invest for this creditor?
Asaf
I don't know about results in the field,... I would love to receive information about it. Energy from nuclear fusion always
is 40 years in the future and has remained so for the past 50 years. The French indeed
They carried out a nuclear test, but as far as I know about it, the test has nothing to do with lasers, I would be happy
get information about that too. Today the experiment at NIF is the most advanced in the field as far as I know.
The focus of the lasers was not uniform, but today I think they are able to focus about 180 laser beams
On a single point..
When the French conducted an atomic (perhaps hydrogen) experiment (during the Shirk period). The activation was with the help of a laser mechanism. Therefore, there is a research infrastructure, in laser nuclear fusion. That experiment angered the Australians, they blew it up in the ocean in front of the coral reef.
Ehud, it is true that there is a certain difficulty in the stability of the magnetic force. But there are already results in the field, with symbolic electricity generation. But there are also problems with the stability of the laser (the focus is not uniform), and in the world most of the research focuses on maintaining the plasma with a magnetic force.
Lorem
There is always a reason to look for alternative methods (unless you are CEO of an oil drilling/refining company, as you wrote).
This is the driving force behind science and humanity.
The magnetic process is so successful that if they hurry to develop the method they will get to see the first commercial power reactor far in the late forties of this century, and this is in a world where the problems of utilizing fossil fuels to produce energy are known and known to anyone who is not the CEO of a company oil.
There really is no reason to look for alternative methods.
Asaf,
Nuclear fusion is not performed at all using the magnetic force method. First the magnetic fields only constitute
A potential (a kind of vessel that captures the gas) that captures the hot plasma. The heating is received from currents
electricity and electromagnetic radiation (microwaves). Magnetic confinement fusion has complicated problems
of magnetic instabilities with which they have been entangled for decades without a solution. fusion using
Laser is a much more promising direction at the moment.
It is interesting that nuclear fusion is carried out regularly, using the magnetic force method. And the process is so successful that there is an international project for a fusion reactor in France (Iter). The laser method is only being tested in America, and has not yet achieved impressive success. The laser research is budgeted, because of a military application.