A new process, which simultaneously utilizes both the light energy and the heat energy of solar radiation to produce electricity, may yield twice the efficiency and more than that of solar cells that exist today. This is what engineers from Stanford University claim
A new process, which simultaneously utilizes both the light energy and the heat energy of solar radiation to produce electricity, may yield twice the efficiency and more than that of solar cells that exist today. This is what engineers from Stanford University claim, who discovered the process and proved its activity.
The process, known as "photon enhanced thermionic emission", will be able to reduce the production costs of solar energy so that it can be competitive with oil as an energy source. Stanford University engineers have discovered how to simultaneously use light and heat from the sun to generate electricity in a way that could make solar power production more than twice as efficient as existing methods today, making it cheap enough to be competitive with oil.
Unlike the photovoltaic methods used today in solar panels - where the efficiency decreases as the temperature increases - the new process actually excels at high temperatures. The innovative process has the potential to obtain higher efficiency than thermal or photovoltaic conversion methods.
"This is a real conceptual breakthrough – a novel energy conversion process, not just a new material or a small change," said Nick Melosh, professor of materials science and engineering, who led the research group. "This is actually a completely different method of utilizing energy." And in addition, the materials required to build the facility that utilizes the method are cheap and readily available, meaning - the energy produced through it will be economical. The research findings were published in the scientific journal Nature Materials.
"Demonstrating that the process works was a big deal for us," said the lead researcher. "And we showed that the physical mechanism does occur and works as we predicted."
Most photovoltaic cells, such as those found in solar panels on building roofs, use the semi-conducting material Zoran to convert energy from the photons of light into electricity. However, these cells are able to use only a small percentage of the light spectrum, while the rest of the radiation is converted to heat.
This heat, which originates from unavailable radiation from the sun, and limitations in the efficiency of the cells themselves are the source of the loss of more than fifty percent of the initial solar energy reaching the cell.
If this heat energy could be harnessed in some way, then solar cells could be much more efficient. The limitation was that high temperatures are required to operate heat-based conversion systems, while solar cell efficiency decreases sharply at high temperatures. To date, no one has been able to find a way to combine heat conversion methods and solar cells.
The group of scientists discovered that by coating a piece of the semiconductor material with a thin layer of the metal cesium, the material could utilize both light and heat to generate electricity.
"What we have shown is a new physical process that is not based on normal photovoltaic mechanisms, but one that is capable of producing a photovoltaic-like reaction at high temperatures," explains the researcher. "In fact, the process works better at higher temperatures. The higher it is, the more efficient the process is."
While silicon-based solar cells become inactive as soon as the temperature reaches 800 degrees Celsius, the innovative device does not reach its peak efficiency until above XNUMX degrees Celsius. Since the system works optimally at temperatures that are far above those reached by normal solar panels, the device will work best inside a solar radiation concentrator such as concave plates (satellite plates) that reach a temperature of XNUMX degrees Celsius. Plates of this type are used in large solar farms such as those existing in the Mojave Desert in Southern California and which often include a heat conversion mechanism as part of the engineering design, which allows another opportunity for the new device to help generate electricity.
Photovoltaic systems never reach temperatures high enough to allow utilization of the excess heat by heat conversion systems, while the high temperatures at which the new system operates are perfect for utilizing this heat. The researchers calculated and found that their system would reach an efficiency of fifty percent for a solar concentrator, but if it is also combined with a heat circulation system, the efficiency may reach 60-55 percent - almost three times the efficiency of existing systems. The engineers are interested in designing the new devices in such a way that they will fit into existing systems, so that the conversion process will become economical enough.
The researchers used the semiconductor gallium nitride in their experiments for the proof of concept itself, as it was the only material that could withstand such high temperatures. In experiments with this material, the efficiency was indeed less than expected, but the researchers believe that they will be able to find the appropriate material, perhaps gallium arsenide, or another, in which the calculated efficiency will indeed be obtained. Another advantage of the system lies in the fact that the amount of semiconductor material required is quite small. This fact will also greatly contribute to reducing costs.
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Since the debate, the virus that attacked industrial facilities in Iran, India and Pakistan has been published, and estimates have been published that it was an Israeli or American attack. Anyone want to reassess their faith in nuclear reactors?
Regarding the claim that a nuclear reactor is not a nuclear bomb: it is a nuclear bomb that explodes slowly. In the reactor there is far beyond a critical mass of fissile material, and the explosion is slowed down by electron-absorbing rods. If something happens to the rods, such as melting or extraction due to a malfunction - the reactor works as a bomb mod. A few scientists have already died because they accidentally brought two lumps of fissile material together - and reached a critical mass.
Something interesting to see here:
http://en.wikipedia.org/wiki/Renewable_energy_commercialization
In 2008 for the first time, more renewable energy than conventional power capacity was added in both the European Union and United States, demonstrating a "fundamental transition" of the world's energy markets towards renewables, according to a report released by REN21, a global renewable energy policy network based in Paris.[22]
Eddie
The problems you raise are particularly relevant to the State of Israel for which the issue of a nuclear power plant is not relevant at all.
Note that a nuclear power plant is not a bomb and cannot be the opposite! In my opinion there is more danger in a hydroelectric power plant where terrorists blow up a dam and cause a massive flood, but I don't hear people making such claims. Terrorists can do more damage blowing up chemical facilities than a nuclear power plant but I'll stop there to mark targets for terrorists.
As mentioned, 30% of the electricity consumption in the USA is provided by nuclear power reactors and in France it is 80%
To this day I have not heard of such a reactor being attacked by hostile elements. I know that it is not possible to prove by induction that such an attack will not happen, but many of the countries of the world are safe enough to generate electricity in reactors. Note that there are more than 400 power reactors in the world. In addition, since the existence of nuclear power reactors, an operating reactor has never been bombed and such an action would definitely be a violation of a red line for a country to do so. Beyond that, nuclear reactors can be protected by various means.
Terrorists can also eliminate the government of a country with a bomb, which will cause chaos, but this fact does not prevent holding elections and appointing ministers. In conclusion, the fear of addicts is much more psychological than realistic. In the largest nuclear accident that occurred in Chernobyl, most of the dead were firefighters who extinguished the fire.
sympathetic,
Even if we assume that generation 4 is quite secure, beyond concerns about reactor accidents - there are also concerns about terrorist elements and terrorist states taking over nuclear technologies - and nuclear means, including nuclear power plants, potentially XNUMX of which are a terrible bomb. There is the fear of reactors exploding due to warlike actions of enemy countries.
Unfortunately, there is nothing that guarantees humanity today from the possibility of the deliberate destructive use of nuclear reactors, as well as the capabilities and advantages resulting from their operation and exploitation, by terrorist elements of all kinds, or of detonating reactors in war operations.
In my opinion, a principled priority for the development of solar or green energy sources follows from this. I believe that in the end, after adequate investments, they will find satisfactory solutions to the energy supply problem - and these will save humanity the existential risk of needing nuclear reactors.
sympathetic:
Thanks for answering my concerns about nuclear power even though I didn't say I had such concerns.
I explained what I think is the state of mind in the public - a state of mind that you also referred to.
It's a mindset that exists and has a lot of power.
Regarding the availability of energy sources - why don't you look at what is happening today regarding mineral energy? Do you see a problem with oil funding terrorism? Aren't you aware of all the conspiracy theories that crop up every morning about the "real reasons" for all kinds of wars?
Energy independence is a goal that countries strive for.
They manage without her but that doesn't make them not aspire to her.
Do you disbelieve in that?
Do you think the fact that you don't see it as a problem will influence any leader of any country?
I was afraid that you would take the historical view to the point where you took it and I hope you are clear that this is demagoguery.
First of all, it is the energy of fusion and not of fission.
The situation in this field is much more far from perfect than the field of solar energy.
And between us - if you want to play with words - then what I propose is exactly this - solar energy is fusion energy so if you really stood behind what you say - you would not rule out solar energy but claim that it is a special case of nuclear energy.
Regarding the costs of solar energy - they are not that high and are becoming cheaper.
Do you think there are no people in the leadership of any country in the world who know how to count?
Why are all countries going in this direction?
So fine - say they don't know how to count, but the more you claim that their accounting error is greater, the more you will have to admit the power of the public mindset that you tried to solve by trying to calm me down.
As I mentioned - biofuel is a successful form of solar energy storage.
There is also progress in other forms of energy storage and to the best of my memory there are also several articles on this here on the website. Even pumping water to a high place is a successful form of energy storage.
My logic is not the other way around.
I explain what they are looking for and point out that this is the only solution to what they are looking for.
But know what?
All this preoccupation with prophecy seems silly to me. We'll see. I really don't care how the problem is solved in the end - the main thing is that it is solved.
First, regarding what you call a "historical view" take it another step back... most of the energy on Earth originates from nuclear reactions that the sun mediates for us. Why not cut out the middleman and enjoy nuclear energy directly. Although today we know how to produce controlled energy from fissions and not from fusions like in the sun, but it is possible that in the future there will be other options.
As for your logic, it seems the opposite to me. You start from the premise that renewable energies must be the solution because any other type of energy source will be depleted and therefore the solution is renewable energies. That is, what must be the solution is the solution. For me, this is reverse logic, there may be no solution, if something comes and shows that the costs of solar energy are too high, even though it is renewable energy, for me, this is not the solution. It is possible that the solution in the short term is nuclear energy which will be enough for the hundreds of Korob and then who knows.
You mention continuous progress in the fields of renewable energies and in particular solar energy, but in my opinion the major problems have not been addressed at all: energy storage and low efficiency. There is a lot of public relations for renewable energies but I don't see progress on the horizon mainly politics.
Regarding your concerns about nuclear energy. First generation 4 reactors are supposed to answer the problem of securing the fissile material. The reactors are designed so that their fuel cannot be used for military purposes. Second, today's miners are much, much safer than those used in the former USSR. France provides 80% of its electricity consumption through reactors and I have not heard of an accident in a French reactor. The new miners are supposed to be completely safe. What happened at Chernobyl is a combination of poor planning, poor safety regulations and serious human error. What happened in the Eastern Bloc is unlikely to happen in a democratic country with safety supervision in its reactors. In conclusion, nuclear energy is a mature energy source that has undergone several improvements over the years and generation 4 reactors are supposed to answer the security problems (preventing the possibility of producing weapons), safety (they are supposed to be inherently safe), efficiency (they are supposed to have high efficiency) and perhaps the most important of all Should produce some nuclear waste of long-lived radioactive elements.
Regarding the equal distribution between countries, I don't see it as a problem, the other minerals are also not distributed equally, and yet the world is managed by free trade. Regarding the solar energy that is apparently equally distributed, I do not agree that the northern countries have very few sunny days, nor do all the countries have enough empty areas (deserts) to be able to utilize the solar energy, so there is no equal distribution on this issue either.
Very interesting article.
It is also interesting to look at things from a historical perspective:
For most of the years of the earth's existence, almost all life on it was based on solar energy (all except for a few tiny creatures in the depths of the sea).
Most of the mineral energy we consume today is nothing more than solar energy.
Bio-fuel, which has received a lot of investment in recent years, is solar energy for a penny (only different from mineral energy - here it is renewable energy).
My confidence comes from a number of reasons.
I mentioned two of them:
One is that in all the areas you mentioned there is constant progress.
The second is that there is a tremendous amount of this type of energy and it is truly renewable.
Reasons that I did not mention partly stem from the second reason and partly contribute to the first reason:
One is political/sociological/rational: the public has a fear (which is difficult to claim with unwarranted confidence: earthquakes are important, for example) from the use of nuclear energy.
Another reason is the fear of the connection between nuclear energy and the ability to develop a nuclear bomb.
Another reason is the much greater degree of energy independence that countries can achieve (sunlight falls to one degree or another on all countries while only some of them have uranium ores)
Michael
A much more mature alternative is nuclear energy (not relevant to Israel). In France, 80% of electricity consumption is provided by nuclear reactors, in the US it is 30%. The technology of nuclear reactors has already gone through several stages, currently it is about generation 4 reactors, there is no place at all for comparison with solar energy. The main failure in nuclear energy is the psychology of the movie "The Chinese Syndrome", together with the malfunction in the reactor in the USA (the death of one technician if I'm not mistaken) caused the complete braking of nuclear energy in the USA about 30 years ago. Today there is a return and decline in the field. I don't see significant progress in solar energy or a wobble with the fundamental problems: low efficiency, storage of energy for long periods of time. Where does your confidence come from?
Solar energy (along with its derivatives - such as the wind and waterfalls) is the main renewable energy available to us.
We currently use only a tiny part of it.
Technology is also advancing quickly.
I'm actually pretty sure that solar energy will be a main - if not exclusive - source of energy in the future.
Noam and also anonymous
When science connects with technology, there is a tendency to make a lot of promises, and therefore also the use of the terms innovative, groundbreaking, etc... The path in which technology develops is: idea, scientific research, development, and marketing, with the last two stages being money-grubbers. It is not enough to find a good idea, it must be shown that it is scientifically valid, then it must be shown that the idea can be used for mass production. Many ideas are good on paper but are difficult to produce and fall at this stage. In the market of the idea that does not always reach the final stage, you have to deal with the competition and the existing technology. In all the last stages, investors must be convinced to invest in the product. So far in general and regarding solar energy: First, solar energy is a technology in its initial stages, it suffers from a number of fundamental problems: low efficiency, how to store energy when there is no sun, production cost and the resulting pollution. Even if all these problems are solved, solar energy will not solve the world's energy problems, it will be a small component in the list of alternative energies. There is a lot of public relations and politics in the market for solar energy and other "green" energy alternatives (it is not clear to me that the island's solar energy is indeed green because it follows a production process).
If someone succeeds in carrying out the same process with a different material it will be but justified on their part to say that they came up with the idea first.
Just like between Gamov and Arno and Penzias, it was Gamov who first deduced the existence of the cosmic background radiation.
Comment number 9 is of course mine
Sabdarmish Yehuda
Nevertheless, there is a reason for the flaw in the publication of the article in the manner in which it was published, when the article itself also says that:-
"Although the efficiency was less than expected, the researchers believe that they will be able to find the appropriate material, perhaps gallium arsenide, or another, in which the calculated efficiency will indeed be obtained." End quote.
This is a well-known method of putting the later first so that they will always be cited as the inventors of the idea and claim rights for it. The same will be done with the meteorite from Mars (perhaps), which has the remains of living beings (perhaps), and so in any research that discovers life on Mars (perhaps) they will say we discovered it first (perhaps)
Shabbat Shalom
Sabdarmish Yehuda
You can't see the forest for most of the trees... so many techniques - plastic, hybrid production, and now this process - but in practice - only Luz and its ilk are setting up gas stations with 10(?) years of technology. What is going on here? So much research and money poured in and sometimes it seems that nothing moves...
End:
Moshe Nachmani provides an abbreviated translation of articles published in the scientific press.
The phrases he uses are taken from these articles.
Therefore you have nothing to come to him with claims.
In general - in order to claim that phrases like "innovative" or "groundbreaking" are used too much - you need to show at least once that the phrase was used when it was not justified to use it.
Therefore - even if you transfer your accusation from Moshe Nachmani to the scientists whose articles he translates - still - it cannot be based on statistics that do not refer to the contents.
Regarding the utilization of solar energy for space flights, which Nimrod and Iran brought up - don't forget the solar wind sail.
Nimrod about flights to deep space..
Since we are still so far from such a thing...the easiest answer is "when we reach the bridge we will cross it"
But now really...solar energy, at least at the moment, is not even a candidate to be used as a source of propulsion...the idea of a plasma-driven fusion reactor is still based on a nuclear reactor or a series of active ones...and this is the fastest idea we have...and it is still not fast enough for deep space flights ..if anything more for much faster flights in the solar system..
So there is still time until her name...
More important than anything is that we will no longer need oil, coal or gas and that the places thanks to which they rose and became rich will return to being a desert for their inhabitants.
Is it just me or does Dr. Moshe Nachmani very often (too much in my opinion) use explosive phrases such as "innovative process", "breakthrough" and "for the first time ever" in his articles and articles here? Are other things that are reported on the Hidan website every week less "innovative" and less "groundbreaking" than those that Moshe Nachmani reports on? Is it acceptable to use such descriptions so frequently in objective scientific reports?
This is just a question. And if I'm wrong please correct me, but this is my personal impression after years of reading this site.
They will try graphene
Their idea already existed, but the very success of conducting such an experiment can greatly advance the field of using solar energy, such a breakthrough that will result in the industrialization of the matter within a few years and can make the use of solar energy more efficient and widespread.
When you are near the sun, it is effective, but in what process will it be possible to use the depth of dark space, for example, in space flights far from the sun? Cold fusion?