Valery Ivanovich Yarygin - Doctor of Technical Sciences, Deputy Director of the Institute for Special Nuclear Power Systems of the SSC RF- IPPE. He is the head of the laboratory for the research into fundamental problems of conversion of various types of energy.
TOPAZ, Enisey and space nuclear power systems (NPS) of the second generation
Valery Ivanovich, first of all, let us ask you to tell about the history of the space nuclear research line at IPPE.
The history of the issue began more than 50 years ago, when Alexander Leipunskiy initiated the work in the area of direct conversion of thermal power produced in nuclear reactors into electric power. He worked together with his faithful pupils Igor Bondarenko and Victor Poupko, Vladimir Malykh, "heaven-born" designer-technologist, have joint them later.
The IPPE being the Research Supervisor was from the very outset and is now one of the leading institution in the area of creation of the scientific-technical basis for space nuclear power engineering, including space nuclear power systems (SNPS) with direct energy conversion. The most significant results of the IPPE work are the "BUK" and "TOPAZ" SNPS, which have been developed in cooperation with the Chief Designer (NPO "Red Star", now - FSUE "Red Star") for space vehicles, which have been called earlier the artificial satellites of the "Cosmos" series with different numbers. Now, when our activity became partially open, they are known under their real names. First of all, these "US-A" systems for marine space prospecting and target designation (NPS with thermoelectric conversion of thermal power into electric power, more than 30 launches into orbit) and two "Plasma-A" space vehicles with experimental thermionic NPS.
Thermoelectric SNPS were mass-produced and made a part of national defense. In 1986 a decision was made about the flight-design testing of "Plasma -A" space vehicle with "TOPAZ" thermionic NPP. The first satellite ("Cosmos-1818") with this system was launched on February 2, 1987, the next ("Cosmos-1867") - on July 10, 1987. These satellites had the joint research program and differed by service life -142 and 342 days, correspondingly. By the way, this year we celebrate the 20th anniversary from the launch of the first "TOPAZ" SNPS as a component of "Plasma-A" space vehicle.
TOPAZ was and remains our domestic and world pioneer work. Nobody has done it before us and it is not clear if somebody will be able to repeat it in future. Both our USA colleagues and specialists from other countries did not manage to solve the problem of developing the space thermionic reactors-converters, although they tried to do it. In particular, the Americans worked intensively in this direction in the 1970-s and 80-s for at least 15 years, but they didn't receive so notable results as we did.
Do you mean the "TOPAZ-1" reactor as it is called in many open publications?
First of all, I'd like to remind that TOPAZ (Thermionic Experimental Converter in the Core) from beginning to end is flesh of flesh and blood of blood of IPPE and NPO "Red Star". The abbreviation "Topaz-1" was artificially introduced by our colleagues and competitors from our cooperation in order to emphasize the importance of their development under the title "Enisey".
"Enisey" didn't move further than the successful ground tests of a prototype. However, many people know it under the title "TOPAZ-2". It is not true. Actually, the "TOPAZ" SNPS has its own series - "TOPAZ-1", "TOPAZ -2", "TOPAZ -3" etc., but it is the series of IPPE. It is the natural development of the line, which was laid in our initial concept, the introduction of improvements in the physics, design and technologies for the solution of the problems analogous to those, which were posed for the first "TOPAZ" SNPS.
My colleagues and me are rather sensitive to profiteering in the name of "TOPAZ" and prefer to tell so: there is "TOPAZ", there is "Enisey" and there are other sytemss, which are called now space NPS of the second generation, by the way, the follow the line of "TOPAZ", not "Enisey".
I wouldn't like to talk a lot about the second generation NPS. I'd only like to note that the scientific and technical conference "Potential of NPP Use for Solution of Near Space Problems and Power Supply for Surface Stations and Space Vehicles for Exploration of Far Planets" will be held on November 29-30, 2007, at FSUE "Red Star". A lot of materials about prospective use of thermionic SNPS will be presented at this open conference.
Let's get back to "Cosmos-1818", to "TOPAZ" reactor. Is that right that the reactor was fully designed and developed at IPPE?
This is not true. The "TOPAZ" reactor-converter, or, more exactly, NPS was a part of space vehicle. It is a complex unit, and its creation was an extremely difficult task. Nobody can solve it alone. The "TOPAZ" NPS was developed by cooperation of about 300 organizations, but the main organizations were the Research Supervisor organization, the Chief Designer organization and organization of the Leading Technologist of thermionic fuel elements (TFE). The IPPE was the Research Supervisor and the Leading Technologist organization. Its functions were the vindication of the operating process and characteristics, as well as the solution of all the problems connected with the support of the design studies and developments (including of the converter itself), the design and technology, the nuclear and radiation safety, the putting into operation and decommission, the supervision of ground tests and others.
NPO "Red Star" was the organization of the Chief Designer of "TOPAZ" NPS. I'd like to mention the names of two men from this enterprise, who realized, so to say, the technological policy in the matters concerned with the "TOPAZ" NPS use. These are Georgiy Gryaznov, who was at that time the director of NPO "Red Star", and his deputy Victor Serbin. Unfortunately, Georgy Gryaznov died several years ago. Victor Serbin works in space area as a consultant of V.S Vasilkovskiy, Director General of FSUE "Red Star".
I.I. Bondarenko, V.A. Kuznetsov, V.Ya. Poupko and others from IPPE, G.M. Gryaznov, V.I. Serbin and others from "Red Star" were the key people in the choice of the "TOPAZ" NPS concept and engineering solutions and their realization in the flight tests, when "TOPAZ" was a part "Plazma-A" space vehicles (satellites of "Cosmos" series ## 1818 and 1867).
The problems posed for the test-flight were solved successfully. There was nothing that could be called a negative result. One of the satellites flied, as I have already mentioned, for a half a year, another one - for a year in accordance with the test-flight program. They fulfilled their programs and were decommissioned gradually. Decommission was realized by the satellites withdrawal to a higher orbit of long existence, where the reactor will become absolutely not dangerous after deexcitation during several hundred years.
From Soviet program - to Russian one
Actually, two successful tests of "TOPAZ" completed the Soviet period of the space nuclear power engineering development. In 1986 a tragic incident at Chernobyl NPP happened, one of political consequences of which was an interruption of many activities. Then Soviet Union broke up, and in the beginning of 90-s the development work was terminated, while we at IPPE were then developing the "TOPAZ" followers -"TOPAZ-2" and "TOPAZ-3", in accordance with our numbering.
The most difficult period started, which lasted almost through the whole period of 1990-s. The cooperation created earlier was broken, many specialists went away, and everyone survived as one could. The Russian government declared the so-called defense conversion. What have we not dealing with - milk, separators… Try to imagine such situation. Our colleagues from abroad arrive. They have a colossal interest in our technologies. Digressing, I'd like to say that until now the published materials about "TOPAZ" SNPS have been of mostly promotional character, being really the tip of iceberg. Of course, specialists abroad are very interested in our achievements. So, the foreign delegation arrives and what can we show them? We show them a plant made for defense conversion tasks and designed, for example, for chicken processing. This is a vivid example of a level of defense conversion in the case of direct energy conversion technologies in the 1990-s!
By the way, the situation at IPPE was different. We managed to find the defense conversion work, which is now called correctly the diversification of technologies for civilian use. We found a problem connected with the direct energy conversion and related to power-saving technologies. Due to this ground conversion problem, which we solved together with our colleagues from the Netherlands, we managed to keep the key specialists and support technologies. The work completed in 1997 by the creation of a prototype - of course, for the Netherlands, not for Russia. Nevertheless, even at the most difficult times our people didn't go away "to dig holes and sell sunflower seeds". Our main specialists continue to be engaged in the direct energy conversion technologies.
I have already mentioned that the first satellite with "TOPAZ" reactor was launched on February 2, 1987. Eleven years later, in 1998, practically in the same day, there occurred another important event, which put an end to troublous times for nuclear space. The RF Government Chairmen V. Chernomyrdin signed then the Resolution #144 "On the Concept of Development of Space Nuclear Power Engineering in Russia".
An extract from the RF Government Resolution # 144.
Since 1990 in connection with difficult economic situation, as well as with change of geopolitical situation in the world, the work on creation target space complexes on the basis of nuclear installations in Russia was ceased that is a factor of strategic risk. Absence of necessary research and design reserve for nuclear installations having long cycle of development and creation can influence negatively on military and strategic safety of Russia.
This situation requires an adoption of measures directed at keeping by Russia the leading positions in the area of nuclear installations and creation of research-technical reserve providing by 2010 a possibility of solving strategic tasks using nuclear installations in the interests of defense, economics and science.
The main task of activities in the area of space nuclear power is a concentration of limited financial resources and efforts of developers on the top-priority lines of activities for development of unified base assemblies and key elements of nuclear installations providing in future a creation of nuclear installations with power up to 100 kW and lifetime of 5-7 years in short period.
In my opinion, it is difficult to overestimate the importance of this document for specialists working in space area. The Government put an end to the decay of our research line. This action made a promise to cooperation and specialists - be patient for some more time! Our work today is kept at a level of research work and support of main technologies, i.e., this is the work for survival, but with potential for development…
Resolution #144 did not have such an important part as financial. Nevertheless, it is very important from ideological point of view. Everything that had been done in our research line in recent years was due to this document. Of course, specialists from all interested departments contributed their share into the preparation of this document.
An opportunity for international cooperation was also very accurately mentioned in this document. The Resolution said that cooperation with foreign countries was possible only on a basis of mutual acceptability and mutual interest. Opportunities for the execution of joint projects were provided. Unfortunately, the West tried for some time to "filter" information from Russia, but later they lost any interest in cooperation with us. One can say with certainty that in space nuclear power engineering the USA accepted a doctrine of relying on its own resources. I think that on the whole the USA stopped the thermionic work just because they were not able to cope with it without Russians.
Features of national nuclear space
Technical question, if you allow. Do thermionic reactors really have advantages over plants of other types?
There is a complex of system parameters of design character for justification of the choice of SNPS as a part of space vehicles for various purposes, which show that thermionic reactors-converters have quite positive advantages.
Today there are exact criteria by which one can judge the research line, which will receive in the nearest future a package of orders for realization. These are the performance characteristics including the limitations on masses, overall dimensions etc. The thermission has here very good prospects of winning. The competitors of space vehicles with thermionic NPS are the ones with the solar, thermoelectric and machine (dynamic) converters.
Machine conversion - the gas turbine power plants (mainly a Brayton cycle).
Even in the opinion of the USA experts, the thermionics has advantages beginning from the level of the electrical power consumed by space vehicle of 50-100 kW and more up to submegawatt level and even up to several MW. However, in my opinion, the winner would be the country, which will be able to bring its national experience in the area of nuclear technologies to the creation of a real prototype.
Experience varies. The positive experience in Russia was obtained with "TOPAZ" SNPS, therefore we stand up for thermionics. We have every reason for that as we preserved specialists and the Chief Designer ("Red Star"). Instead of the lost production base in Estonia (for the "Enisey" NPS) we have our own base in Russia. In the other words, the whole problem of the thermionic line development is enclosed in Russia and we'll not depend on anybody. And if we could receive more of the state support, everything would be excellent. As to the Americans, they direct their efforts to the gas turbine power plants. It is their national technology based on the aviation propulsion technologies of "Boeing", "Lockheed" and other corporations.
I'd like to repeat that the winner would be the country, which will be able to realize its national technology in the space vehicle similar to "Plasma-A" and other pioneers of the space age. Naturally, the created space vehicle should meet the requirements of a customer, and it will be, by definition, an order for the dual-use space vehicle.
It is important to understand that nobody will profit by the old decisions. One should search for the new operating processes (conversion processes), the new design concepts and new technologies, which will make it possible to realize all that. We are here still at the stage of research work, which was designated in the governmental Resolution #144 of 1998, with the only difference that we are actually completing this stage and it may be that with the state support we will pass on to the stage of development work.
Let's talk about the development work, if possible. As we know, the Americans had the projects of NPS not only for satellites, but also for interplanetary flights, for example, to Jupiter's moons.
You are right, such projects exist. For example, the project for flights to icy moons of Jupiter you mentioned, it is called "JIMO" (Jupiter Icy Moons Orbiter). But it was officially suspended in August- September 2005, as you know. The reason for the suspension published in the open literature was that this project is long, expensive and not sufficiently validated.
You see, the Americans have no experience. The Russians have this experience ("TOPAZ"), while the American experience of the gas turbines' use is restricted by aviation! Moreover, practically every year "Roscosmos" proposes to the Americans the cooperation in the context of global problems, for example, the Moon base. As you know, the Americans set the task to create the base on the Moon and chose the suitable place. By the 2030-s the stationary base should start functioning with a gradual increase of the level of its electrical power. Russia proposes cooperation, but receives only negative responses.
The same concerns the flights of the JIMO-type space vehicles. This is an extremely complex and very expensive project. If there are no "exterior" considerations, of course, it makes sense to combine here the efforts of many countries. But we see absolutely the same situation - the Americans either don't want or may not resort to the help of the Russians.
In the vanguard
I mentioned already that we at IPPE managed to retain the complexity in respect of all systems of space NPS, including the converter proper, the reactor core, the control devices, the moderator, radiation shielding, cooler-radiator technologies, the liquid-metal coolant technology, the calculation technique, the experimental base etc. We preserved the methodic and calculation system. We have experts, facilities, technologies and work, which has never been stopped or frozen in any circumstances. Though, of course, the scope and the level of work have changed. What we are doing now - it is, certainly, the research work.
Besides, we have the state leading scientific school named Direct Energy Conversion under the leadership of Anatoliy Zrodnikov, which is in the vanguard of the research attack on new design concepts. This school is trying to find the new processes, to confirm them at the laboratory level and to describe them. This is what one calls science, or, in the modern formulation, the problem-oriented fundamental studies.
The school was officially registered two years ago. With a small but purposeful state support, we work in the area of the scientific and technical basics of thermionic converters (TIC) with the so-called Rydberg matter. It is very promising "layer" type of the low-temperature high-performance thermionic converters, which seems to be attractive for both space and ground purposes.
Rydberg matter - the condensed excited states in alkaline metals, e.g. cesium, containing the Rydberg (highly excited) atoms and molecules. The possible interelectrode medium for the low-temperature thermionic converters could be the condensed excited cesium, which at the temperature of about 700 K has the high electrical and the electron work function less that 1 eV. The condensed excited cesium has been studied in recent years in Russia, and earlier, in 1990-s, it had been studied in Sweden. During the laboratory experimental study and test of these TIC at IPPE the efficiency of about 25% was obtained for the first time.
It is difficult to say what would be the output of the school. But I'd like to mention that our school is the only one in Russia.
In Russia or in the world?
Certainly, there is no such school abroad, because all the science in the space nuclear power engineering is the Russian science. And in Russia, our school is the only one.
We have three main directions of work in the school - the direct conversion of the laser energy into the electrical one (under the leadership of P.P. Dyachenko); the electrochemical conversion; the new thermionics and the applied research in the field of thermoelectricity represented by my colleagues and me. What are we waiting for? We are waiting for a more considerable state support, which may help us to pass from the research on to the development work.
The IPPE is the leading scientific school in the field of direct energy conversion not only today, basically it was such a school earlier too: we published the first monograph on the physics of low-temperature plasma and thermionic processes. This monograph based on the works of our teachers - I.P. Stakhanov, Yu.K. Guskov, V.P. Pashchenko, A.S. Stepanov. It was published in 1968 and has been reprinted many times. By way of machine translation it somehow appeared in the USA. In the United States, this monograph was translated into English using the machine translation. All other scientific schools published their monographs later, e.g., the Leningrad school did it at the late 1970-s.
First Russian monograph on the physics of low-temperature plasma and thermionic processes - I.P.Stakhanov, Yu.K.Guskov, V.P.Pashchenko, A.S.Stepanov. Plasmic Thermionic Energy Conversion. Moscow, Atomizdat, 1968, 392 pages.
So, we preserve our scientific traditions and try to develop them. Some of our experts are the followers of Stakhanov and Guskov. Unfortunately, both these famous scientists have passed away, but their followers are alive and continue working.
In point of fact, you are keep the knowledge in the field of the nuclear space?
Both keep and develop. Thanks to school, we obtain an interesting experience of diversification. For example, we used the BUK technologies for the creation in the interests of Gazprom of thermoelectric plants with the required high power level, up to 500 W and higher. Nobody did it earlier, except our competitors in Canada. However, our competitors already sell their plants to Gazprom, while we are so far in the process of application in industry.
For our personnel, such work is the possibility to raise extra money. It is important, because the salaries of our experts are still not satisfactory.
In the context of the school, we carry out the purposeful preparation of the young people in the process of continuous training. In Obninsk there is the only in Russia Technical University for Atomic Power Engineering. A couple of years there arrived the department for advanced methods of the energy generation and conversion (Head of department - Anatoliy Zrodnikov). I give there the course of lectures with the same name.
How is the continuous training arranged? We start working with the students when they are in their fourth year of study, for a year we give them the lectures on the physics of the operating process, materials etc. In their fifth year of study the students carry out the training research work at the IPPE laboratories, in their sixth year they work on their degree thesis, and then some of the graduates start working at IPPE. I would estimate the efficiency of this system as equal to 30%, which is rather high in our time. So, I am rather optimistic about our future.
Apophis requires unity
Well, let's try to discourse on the possible medium-term and long-term orders. Both the Russians and the Americans discuss the dual-purpose space vehicles, the Moon base, the flight to mars, the Earth probing, the communication and telecasting. The "Scientific Tasks" section is somewhere in the end of the list of possible tasks, at that among the medium-term or even long-term tasks. This section has a subsection - the asteroid probing, the monitoring and control of the asteroids, large meteorites and other space bodies. The solution of this problem will require not the submegawatt, but the megawatt power, and it has been put off till 2020-s and later.
It seems to me that very soon - literally speaking, tomorrow - the asteroid control might become the top-priority problem. Recollect the 99442 Apophys asteroid. It was discovered some years ago by the observers from different countries, and it was found that this sky body would cross the Earth orbit at a distance of 40 thousand kilometers from our planet. For the Universe, the 40000 km is really nothing, you know.
This asteroid is relatively large, and its collision with the Earth will lead to the biggest catastrophe comparable with the one that entailed the destruction of dinosaurs. I guess that the Roscosmos chief Anatoliy Perminov had strong reasons to declare the Russian project of creation of anti-asteroid protection for Earth by the year 2026.
99942 Apophis - previously known as 2004 MN4 - was discovered at June 19, 2004. It caused a short period of concern in 2004 when the initial observations gave the 2.7% probability of its strike with the Earth in 2029. Later on, it was shown that it will pass on the 30000-40000 km distance from the Earth. Still there is a probability that the Apophis will go through the gravitation trap and its trajectory will be changed, so it would appear a probability of strike at April 13, 2036. The asteroid dimensions are some 250 meters.
The impact probability for April 13, 2036 is now estimated as 1:45000. However, the Planetary Society was offering 50,000 dollars award for the best plan how to put the tracking device on the Apophis.
Unexpectedly for us all, the Apophis can change the priorities in the space program, because is will be the matter of the mankind survival. We have to start working today, or even had to do it yesterday. Even more, if the Apophis danger level will rise, no country would be able to save the Earth alone. It could be done be the international cooperation only, and we have to join our efforts in spite of our "love" to each other.
How to prevent the strike? It is impossible to destroy it, because instead of one big body a lot of fragments will strike the Earth. The only way is to change the asteroid's orbit - to "catch hold" of its mass (the so-called gravitational tractor scheme) or to start evaporating it (as a rule, asteroids are friable).
Someone has to attend to it! First, one should place a beacon on the asteroid and monitor its trajectory continuously, i.e. one should be able to fly to the asteroid and to land the descent vehicle on it. Next, for evaporation one should create the light source to be placed near the asteroid. Certainly, it will be impossible to solve these problems without the SNPS.
Plutonium fast food
Let us pass on to more optimistic topics. As far as we know, the IPPE published a work with a title more pertinent to science fiction - "Application of Nuclear Photon Rockets for Exploration of Far Space". The authors propose to create for the flights beyond the Pluto orbit the photon propulsors based on the high-temperature reactors.
Right, such work has been done at the IPPE and was published. The idea belonged to the deceased Viktor Yakovlevich Poupko. He and his colleagues, first of all, Andrey Vladislavovich Gulevich, developed this idea.
Today it seems really fantastic from the point of view of all kinds of expenditures. This is the technology for the day-after-tomorrow, rather than tomorrow. But as a physical concept, which does not principally contradict the Earth technology, this idea has the right for existence. The high-temperature reactor, most probably the gas reactor, with the fantastically high temperature level (from our today point of view) should be used there. Nevertheless, this closed problem was theoretically discussed and published.
The nuclear photon propulsors permit to provide the flights with the distances of 100-1000 a.u. for 25-50 years within the "reasonable" for today limits of expenditures and technologies. For example, if we need to go for 1000 a.u. during 25 years, our ship will consume 16 metric tones of fuel, and the reactor power should be equal to 2,000 MW(thermal). Unfortunately, the interstellar flights are still out of the human capability, because the distance to the nearest star exceeds 250,000 a.u.
The source of energy for a photon rocket could be the high-temperature gas-core (uranium hexafluoride) nuclear reactor. The authors propose also another option - the use of the pseudo-liquefied reactor core, where the fuel is in the form of crumb and is kept in the reactor core by the vortex flow of gas (helium-xenon mixture).
When, in your opinion, the nuclear reactors will become the main direction in the development of space vehicles?
Again I refer you to the Apophis. The situation can change. Yesterday it seemed that the first users of the space reactors would be the people dealing with the dual-use technologies. Today, I think, the anti-asteroid protection tasks can receive the main priority. If something threatens to drop on your head in several years, you will take appropriate measures to avoid it.
I can not give you an exact answer to your question. I think it is the time period when we in Russia develop the basic solutions, also concerning the dates.
We hear very harsh estimates that it is unreasonable to use the NPS for satellites…
There is the international document approved in 1992 by one of the United Nations specialized committee. It does not forbid to place the nuclear sources outside atmosphere, but it states that all the dangerous factors should be eliminated, and the nuclear reactors should be used in space only if there is no other alternative.
Let's return to the satellites. When we talk about our everyday life, there is no great need to use nuclear reactors. But when we talk about special purposes, such as the anti-asteroid defense, we must understand that we can not solve it with the solar batteries. One more example of such special task is the flight to other planets. As is well known, the solar intensity drops inversely to the squared distance from the Sun.
Let us try "to speculate" on the foreign experience. The Americans also placed in space about 30 objects in the context of their nuclear program, mostly the radioisotope thermoelectric generators (RTG). They have the Prometheus program with the subprogram for the development of radionuclide technology realized in RTG.
The RTG electrical power is 150 W. This power is generated by rather a big cylinder comparable with a two-month piglet. In this cylinder there lies approximately 13 kg of 238Pu! Can you imagine it? It is approximately the same mass as the was the mass of uranium dioxide in the TOPAZ reactor, but it was the uranium, not highly toxic plutonium... Even more, the Americans install two such generators in the Cassini space vehicle.
The 238Pu is not only very expansive, but also very dangerous isotope. If, Lord forbid, an accident will happen during the launch, we should remember that the injurious factors of the 238Pu would multiply exceed the injurious factors of those isotopes that are produced in the reactor with the uranium fuel However, the United States launched already about 30 space vehicles with plutonium generators and are going to continue this program. They also sell such satellites to the European Union. Figuratively, just like the fast food damaged the bodies of the Americans, these radioisotope generators damaged the space nuclear program of the USA.
In general, however, an example with RTG shows that any idea could be realized if so needed for the solution of national problems. In the American space program you may find the clear statement - if the space vehicles with the nuclear energy sources will obtain the new quality, they could be applied.
Well, it was an answer to your questions about what is expedient and what is inexpedient.
Thank you. The last question, please. May be the USA lag in the field of nuclear space is caused by the fact the space NPS use the fast reactors, and the United States have difficulties in this area?
It is doubtful. The fast breeder reactors in the big nuclear power engineering and the fast reactors for space NPS - these are two big differences, as the residents of Odessa city say. Actually, it is not so much the reactor neutron spectrum that determines its space application as the system criteria: the "kilogram-per-kilowatt" of the whole plant, its dimensions compared to the dimensions of the whole space vehicle, the life time etc.
The "TOPAZ" NPS is the intermediate reactor, while the BUK reactor is the fast reactor, and both use the liquid-metal coolant. For the NPS electrical power level of 150-200 kW the fast reactors would be required. Each time it is necessary to optimize the NPS by the system criteria as the space vehicle component.
Thank you for interview for AtomInfo.Ru.
DATE: December 10, 2007