With the correspondents of AtomInfo.Ru web-edition speaks a Chief Designer of The Dollezhal FSUE NIKIET, doctor of science Vladimir Petrovich Smetannikov.

Space nuclear energy is a "locomotive" of the development

I have been working at NIKIET since 1959. In spite of numerous proposals I have never left the institute, because I don't like very much administrative posts and prefer the combination of science and practice.

Speaking about that professional activity, that I have been realizing for about a half of the century, different directions can be defined there. But all of them, in any case, deal with the high-temperature energy generating methods. These were the first magnetohydrodynamic facilities, that were made with Evgeny Pavlovich Velihov. As you know we all "came out of the naval technologies", so I also had to be engaged with submarines.

As a result I was brought to the work on high-temperature reactors, first of all, space ones. The most significant result of this activity became a creation of IVG.1 reactor on the testing ground in Semipalatinsk. I want to stress that nobody in the world could come close to the parameters reached at this reactor. At IVG.1 were received the results, that can be called a corner stone of the creation of the energy propulsion complexes for the flight to the Mars.

IVG.1 reactor was launched at the stand complex "Baikal-1" in 1975. Reactor was destined to the full-scale testing of fuel assemblies and of reactor active zone modules for the reactors of the space propulsion systems. To 1988 4 pilot active zones were tested on it (more than 200 gas-cooled fuel assemblies for the space propulsion nuclear systems).

In 1990 reactor was modernized and on its base was creates one more water-cooled reactor IVG.1M, that was used further for radiation and experiments over the materials, including also space ones.

Its my firm believe that energy generally and space energy specifically are the break-through technologies of the 21 century. We can?t go on eliminating the organic part of our planet all the time. Real limitations have appeared that make us convert to other types of fuel - at least that don't produce CO₂.

New space energy should be based on new technological decisions. They should consider modern achievements in the sphere of computer technologies, materials nano-structuring and a lot of other. For example it is obvious that such long flights, as s flight to the Mars, can't be based only on the materials that we have nowadays.

We will need other constructional materials - more solid and lightweight. Nano-structuring technologies can cope with this task. As you see nuclear energy and specifically its space direction becomes some kind of the "locomotive", aimed to pull up all the other spheres and push forward many technologies that are not widely adopted.

There is one more aspect that shouldn't be forgotten. Space always attracts youth, and it is very important when there is a lack of specialists in the industry.

To the Mars and to the Moon -using only nuclear energy

What are the main advantages of the space nuclear energy? It removes two principal drawbacks of any other system. At first it is not oriented on the Sun and is not limited with the capacities, that give chemical fuel sources. Second, it gives inexhaustible energy supplies by the acceptable weight and dimension characteristics of the facility - speaking the other way, gives the possibility to realize long flights with the full energy provision.

Peculiarity of the space nuclear energy today is that the demands to the capacity are growing. For the exploitation of the ISS is needed more than 100 kWe, that are provided by the sun panels. It makes additional problems for the station - for example, it should be always oriented properly on the Sun.

Certainly we are still flying on the orbits where using of the nuclear energy is not very expedient. Besides, we should always think about the consequences. I am sure, that it is possible to work with the nuclear energy only on those orbits, that would completely exclude unsanctioned - it means without our command - returning of the vehicles to the Earth.

But for such flights as piloted flights to the Moon or, moreover, to the Mars, we need the systems with the capacity of some hundreds kWe or mWe. No any sun battery can solve such a problem and it means, that help of the nuclear energy will be needed.

What functions will have the energy by the flights to the other planets? First function is providing of the engines operating. Propulsion itself is an energy, big energy. By the way, to reach the Mars nuclear fission engine should work only 10 hours (5 to go there and 5 to go back). And it is very important to stress, that nowadays we managed to come closer to such characteristics at testing grounds.

Second function of the nuclear space facility is connected with producing of the great amount of energy. On the Earth a man needs up to 20 kWe×hour daily for the comfortable life. Much more energy will need the participants of the inter-planet expeditions.

Problem of "compatibility" of a man and reactor in space, that we can hear sometimes, is not an intractable. By the flight to the Mars main danger will come not from the working reactor, that will be properly shielded, and also we will provide its "remote" location from the place where people will be placed.

Main danger will appear by crossing radiation Earth belts. Compare - cosmonaut can get from the reactor a doze of 0.2 Rem and from flying through the belts - 10 Rem. That is why constructions of the ship contain so-called cameras for crossing the belts.

By the way, to minimize the doze cosmonauts should cross these belts as rapid as possible. It is also possible at the expense of using space nuclear engines, but not sun batteries or other energy sources.

But besides "ship" facilities there is one more type of the power generating facilities - on-planet. We should deliver such a station on the Mars or on the Moon almost by the first flight. It will be the foundation of the future base. Sun energy won't give a necessary capacity and that is why we speak about an on-planet NPP.

Certainly there is a proposal to build bases on the poles, where some light is conserved and exists a theoretical opportunity to use sun energy. But on the poles occur storms, that can deactivate sun batteries. By the way, these batteries should be at first delivered somehow to the Mars or to the Moon, that is not an easy task if we remember their weight and dimension characteristics.

I can say that experience, received during the testing is enough to guarantee that we will manage to deliver the on-planet NPP on the Mars and it will work successfully there. But now long-distance space expedition are only plans, prototypes of the on-planet NPPs could be used on the Earth, for example at the North. Such mobile electro stations could find a large scale of implementation in comparison with the floating NPPs.

Certainly, on-planet NPP will differ from the conventional NPPs by its construction. Outside the Earth there are no big stores of water. So, on-planet reactor will be either gas (helium with xenon), or liquid-metal (for example sodium-potassium). Though all my life I have been working on the gas reactors, I don't exclude, that liquid-metal alternatives will be chosen.

The second difference of the on-planet NPP is connected with the absence of the atmosphere and with the necessity to make changes in the heat withdrawal system. If on the Mars it is principally possible to use convection, as there is at least rarefied atmosphere, on the Moon we will rely only on the heat withdrawal by the means of radiating.

These and other aspects of the long-distance space flights are well described in the book issued this year under the title "Piloted expedition to the Mars". It resumed the great amount of work realized in this direction, implemented mostly by Russian specialists. Certainly book contains links to the foreign experience, but determinative - especially in the energy part - were Russian works.

In conclusion I would like to speak about the prospective of practical implementing of our researches. We hope, but we are not sure, that it will be very soon. Certainly hope dies the last and there are certain chances to see Russian space reactors in action again. I can guarantee only one thing - that the sooner it will happen - the less money and forces will be needed for that.

Thank you for the interview for AtomInfo.Ru web-edition.

SOURCE: AtomInfo.Ru

DATE: August 02, 2008

Topics: Russia