Radioisotope Thermoelectric Generators

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There are around 1000 Radioisotope Thermoelectric Generators, or RTGs, in Russia, most of which are used as power sources for lighthouses and navigation beacons. All Russian RTGs have long exhausted their designed service periods and are in dire need of dismantlement. The urgency of this task is underscored by three recent incidents with these potentially dangerous radioactivity sources in 2003—one on the shore of the Baltic Sea, in March, and the most recent two, in the Kola Bay, in November.

In 1992, Bellona released a working paper on 132 lighthouses scattered along the shoreline of Northwest Russia, which are all powered by RTGs. One of them, in fact, is located just a few dozen metres from the Norwegian border.1

Bellona has warned that radioactive incidents involving these RTGs are possible, both because of the decrepit state of these old lighthouses and because the of premeditated theft of radioactive strontium 90, or 90Sr, that is contained in RTGs. Russia’s RTGs that have been used beyond their operational limits have been waiting to be sent to a repository for decades. At best, however, the nuclear installations presenting the most critical case of sitting on the decommissioning waiting list are stored at sites that are neither appropriate for this task nor meet any safety or security standards. At worst, they become prey of “non-ferrous metal hunters,” who crave to make a quick buck on RTGs, disregarding the risk of radioactive contamination to both themselves and other people.

Most Russian RTGs are completely unguarded against potential thieves or intruders, lacking such minimal security measures as fences or even signs warning of radioactive dangers. Nuclear inspectors visit these sites as seldom as once in six months, and some RTGs have not been checked for more than a decade.

But the biggest danger coming from these unprotected RTGs is their availability to terrorists, who can use the radioactive materials contained in them to make so-called "dirty bombs"—bombs that are triggered by standard explosives, but disperse radioactivity. The damage from such an explosion could surpass by many times that from a conventional bomb, with the ground zero area—potentially, dozens of kilometres—remaining radioactively contaminated for years to come.

Radioisotope thermoelectric generators
An RTG—this abbreviation sometimes stands for "radionuclide thermoelectric generator"—is a source of self-contained power for various independent types of equipment with a steady voltage of 7 to 30 volts and the power capacity of a few watts up to 80 watts. RTGs are used in conjunction with various electrotechnical devices that accumulate and transform the electric energy produced by the generators. The most frequent mode of application for RTGs is using them as power sources for navigation beacons and seamarks.2

The core of an RTG is a thermal energy source based on the radionuclide strontium 90—also known as radioisotope heat source 90, or RHS-90. An RHS-90 is a sealed radiation source, in which the fuel composition in the form of ceramic titanate of 90Sr is sealed hermetically and two-fold into a capsule using argon-arc welding. The capsule is protected against any external impact by the thick shell of the RTG, which consists of stainless steel, aluminium and lead. The biological protection shield is configured in such a way that radiation levels do not exceed 200 milliroentgen per hour, or mR/h, on the surface of these devices, and 10 mR/h at a distance of one metre. 3

The 90Sr isotope’s radioactive half-life is 29.1 years. At the time of their production, RHS-90 contains from 30 to 180 kilocuries of 90Sr. The level of gamma radiation reaches 400 to 800 roentgen per hour, or R/h, at a distance of 0.5 metres, and 100 to 200 R/h at a distance of one metre from the RHS-90. It takes no less than 900 to 1000 years before RHSs reach a safe radioactivity level. According to the Russian state nuclear watchdog Gosatomnadzor, or GAN, "the existing system of RTG management does not allow for providing adequate security to these installations, so the situation they are in can be classified as ‘an emergency manifested in the unattended storage of dangerous radioactivity sources.’ This is why these generators need to be evacuated urgently."4

RHS-90
Dimensions of the cylinder 10 by 10 centimetres
Weight 5 kilograms
Capacity 240 watts
Concentration of strontium 90 1,500 TBq, or 40,000 curies
Temperature on the surface, centigrade 300-400 degrees
Exposition dose rate at the distance of 0,02 to 0,5 metres 2,800-1,000 R/h

According to the website run by the Moscow-based All-Russian Scientific Research Institute of Technical Physics and Automatisation, or VNIITFA—the developers of RTGs—radionuclide power installations with high energy capacity operate on plutonium 238, or 238Pu, as their fuel.5 However, using RHSs based on 238Pu—though this design boasts of certain technical lifespan advantages—also demands significant financial input. Thus, in the past 10 to 15 years, VNIITFA has ceased producing such RTGs for Russian consumers for on-the-ground use.

The RTG developers argue that even if an RHS-90 makes it out into the surrounding environment due to an accident or theft from its RTG, the heat source will still remain intact unless forceful means are used to remove it.

According to specialists from the Russian Ministry of Transportation’s State Hydrographic Service, or SHS, "the principal radioactive risk only comes from the sources of ionising radiation based on strontium 90 in RHS-90s." As long as the shell of the RTG is intact—which, to put it in simple terms, is nothing but a transportation case for an RHS-90—it is not considered nuclear waste, say the service’s experts.

"If taken outside the safety of anti-radiation protection, an RHS-90 will present a serious danger on the local level for people who happen to be in the immediate proximity to it. Radioactive contamination of the environment is impossible. No such case has ever yet taken place. An experimental detonation of a powerful anti-ship explosive device that was attached to a small RTG did destroy it, but the RHS-90, which was contained in it, remained undamaged."6a report by the SHS said.

At the same time, while commenting on the known incidents involving RTGs, representatives of GAN and of the International Atomic Energy Agency, or IAEA, have acknowledged more than once the probability of destruction of an RHS capsule through natural forces (see below, Chapter 3.1).

According the latest information available, some 1,000 RTGs are located on the territory of the Russian Federation. Alexander Agapov, head of the safety and emergency situations department of the Russian Ministry of Atomic Energy, or Minatom,7 puts the figure at 998 installations. Other Commonwealth of Independent States, or CIS, countries operate approximately 30 RTGs. In all, the USSR reportedly produced around 1,500 RTGs8. The operation period of all types of RTGs is 10 years. Today, all Russia’s RTGs—without exception—have reached the end of their engineering life spans and must be disposed of.9

RTGs in Russia are owned by the Ministry of Defence, the Transportation Ministry, and the Russian Federal Service for Hydrometeorology and Environmental Monitoring, known by the Russian acronym of Rosgidromet. The Transportation Ministry has jurisdiction over approximately 380 RTGs—or 386, according to various reports—with the SHS responsible for their monitoring and accounting. The Defence Ministry owns 535 RTGs, including 415 RTGs run by the Main Directorate for Navigation and Oceanology.

The SHS says it is sufficient to conduct regular inspections of the RTGs located along the shipping lanes of the Northern Sea Route—from several times down to one time a year—to maintain the physical condition of the installations, and the radioactivity levels on their surfaces and in surrounding areas, in order to ensure safety and security of their operation, including prevention of possible acts of vandalism and terrorism.10

1.1 Types of RTGs
The some 380 RTGs that the Transportation Ministry runs along the Northern Sea Route fall into four types: the Beta-M, Efir-MA, Gorn and Gong.

According to official reports by the Russian State Committee for the Protection of the Environment, "the existing system of RTG management is in contradiction with the provisions of the federal laws ‘On the Use of Atomic Energy’ and ‘On the Radiation Safety of the Population,’ because no physical security or safety has been ensured to these installations. At the time when these RTGs were placed at their locations, no consideration was made regarding the probability of damaging impact effected on them by natural and anthropogenic factors. Due to the inefficient practice of RTG accounting and control performed by the operators of these installations, certain RTGs may be ‘lost’ or ‘abandoned.’. In effect, the sites where RTGs are located can safely be regarded as temporary storage places for highly radioactive waste.11 Especially alarming are the potentially negative consequences of losing control over RTGs operating under the jurisdiction of the SHS and the Ministry of Defence."12

From the 1960s to the 1980s, VNIITFA developed 10 types of RTGs based on heat sources like the RHS-90.

Types and main characteristics of RTGs of the Soviet design13
  RHS heat capacity, watts RHS initial nominal activity, kilocuries RTG electric capacity, watts RTG output voltage, volts RTG mass, kilograms Year of start of mass production
Efir-MA 720 111 30 35 1250 1976
IEU-1 2200 49 80 24 2500 1976
IEU-2 580 89 14 6 600 1977
Beta-M 230 35 10   560 1978
Gong 315 49 18 14 600 1983
Gorn 1100 170 60 7 (14) 1050 (3 RHS-90) 1983
IEU-2M 690 106 20 14 600 1985
Senostav 1870 288     1250 1989
IEU-1M 2200 (3300) 340 (510) 120 (180) 28 2 (3) x 1050 1990

RTGs differ by parameters which variable according to their voltage output, output power capacity, mass, size and other characteristics. Beta-M type RTGs—one of the first designs, which was developed in the late 1960s—have been used most frequently. Today, around 700 RTGs of this type are in operation. However, the joints in the carcasses of Beta-M RTGs are not welded, and, as the past 10 years experience shows, such RTGs can be easily dismantled right where they stand with the help of nothing more than common fitting tools.14 like crowbars and hammers.

In the last 10 to 15 years, VNIITFA has not developed any new types of RTGs.

2. RTG accounting
Besides designing RTGs, VNIITFA also developed their corresponding design documentation, which was then handed over to the plant that would produce the RTGs. Orders for new RTGs came principally from the Defence Ministry, the Transportation Ministry, the State Committee for Hydrometeorology—the Soviet predecessor of Rosgidromet—and the former Ministry of Geology, now part of the Ministry of Natural Resources.

The process of developing new RTGs also involved producing small numbers of experimental power generators. Mass-scale production of RTGs in the USSR was the responsibility of a plant called Baltiyets, in the city of Narva in the former Soviet republic of Estonia. In the early 1990s, the plant underwent major changes, including a re-specialisation, and stopped producing RTGs. Now called Balti EES, the company confirmed in a reply to an inquiry from Bellona’s that it no longer produces RTGs and that it has no information on the precise locations of those RTGs that it did produce or where they were delivered. However, Balti EES’ representatives said that the company’s experts have since the early 1990s taken part in replacing RTGs with other energy sources at Estonian lighthouses.

Putting RTGs into operation was in the 1960s the responsibility of a now-defunct specialised organisation within the structure of the Ministry of Medium-Level Machine Engineering, or Minsredmash—its purposefully misleading Soviet-era acronym that was transformed into today’s Minatom. They were also put into operation by the very organisations that were to operate them.

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5. RTG decommissioning programmes
"This year we’ve signed a technical assignment with the US Department of Energy for dismantling and decommissioning of several RTGs," the head of the Minatom’s safety and emergency situations department Agapov told Bellona Web in September, 200348. According to Agapov, "up to 100 RTGs per year will be decommissioned at Mayak—all the transportation schemes have been prepared, the financial resources have been promised."

Meanwhile, since 2000, VNIITFA has decommissioned only about 100 retired RTGs of various types.49

According to the current protocol, RTG cores are dismantled in a special laboratory at VNIITFA. The RHS-90 may be used for energy purposes or qualified as a radioactive waste and sent in special caskx for decommissioning at the Mayak.

Minatom’s Agapov saw replacing RTGs with safe solar devices as problematic. "At current, replacement of RTGs with solar batteries has been underway for three years, and RTG decommissioning is carried out simultaneously—about 12 RTGs have been decommissioned in this manner. But then a problem emerges—solar panels need to be wiped regularly wiped down so they continue to collect heat energy, and personnel is needed for that."

In 2002, the Russia government launched a programme called "The National Plan of Action for Marine Environment Protection from Anthropogenic Pollution in the Arctic Region of Russia."

Accounting for RTGs was an item of the plan of action. It was, for example, decided to conduct a complete inventory of the RTGs in Yakutia during 2003 and 2003.50 Tamara Argunova, Yakutia’s Ministry for Environmental Protection made the point that the RTGs were, in fact, redundant as most maritime navigations is accomplished with global positioning systems linked to satellites. She encouraged swift and diligent decommissioning of the RTGs in her area.

Rough estimates for the removal and complete decommissioning of one RTG in Yakutia come to 4m roubles51 or about $120,000—the price of installing a new RTG. According to VNIITFA, removal and decommissioning of an RTG in the far flung eastern region of Chukotka amounts to 1m roubles, or $30,000.52

RTGs owned by the Russian Northern Fleet have long surpassed their engineered life span and are considered radioactive hazards. Yet it is Norway’s Finnmark region that foots the bill for their decommissioning and replacement of at least some of them with solar panels.

Indeed, there are several agreements between Finnmark and the Murmansk Regional government regulating RTG decommissioning. As per agreement ecommissioned RTG’s are first sent for storage at Atomflot, the Murmansk region’s service centre for nuclear ice-breakers that are owned by the Murmansk Shipping Company. They are then shipped to Mayak were the decommissioning is completed.

So far, five RTGs have been replace with Norwegian solar panels under one of the agreements between Finnmark and the Murmansk Region, signed in 1998, to swap four RTG’s with solar panels.

The first was installed in 1998 at Bolshoi Ainov Island nature reserve at a cost of $35,400, or NOK 266,000.53 Under the 1998 agreement, another two RTGs were replaced with solar panels in 1999 and 2000. The last, in 2002, was installed at the Laush Lighthouse on the Rybachy Peninsula.

In further cooperation between Finnmark and Murmank, the two regions agreed to decommission 15 more RTGS—12 in normal working order and the three that were vandalised for scrap earlier this year.

In June, 2002, a $200,000, or NOK1.5m, agreement was signed between the regions to decommission yet another 10 RTGs.

In August, 2002, US Congressional representatives and Bellona gathered and discussed the prospects of solar powered lighthouses in Norway near the Russian border. Prior to this gathering Bellona had raised the concern about the nuclear powered lighthouses in Russia.54.

The governors of Finnmark and the Murmansk region, on April 8th 2003, signed two new contracts, one more RTG decommissioning, and the second for testing Russian-made solar panels. By now, 25 RTGs, with a combined activity of 800,000 curies, have been decommissioned in the Murmansk region.

The new 2003 agreement mandates the decommissioning of another 20, one of them a unique project in that it uses six RHS power sources and has an activity of 300,000 curies. This new agreement will cost $600,000, or NOK 4.5m.

That part of the 2003 agreement that will replace RTGs with solar panels will cost NOK 250,000. The Russian panels will be produced in Krasnodar at the Saturn plant, and are cheaper than western analogues.55 They cost about $30,000 each. The solar panel will be designed to accumulates energy during daylight hours, and distribute it to batteries and generators when the sun goes down. The Russian panels will be tested on a lighthouse in Murmansk and a lighthouse in Finnmark.

 

Endnotes:

1. Bellona Working Paper N5:92, Thomas Nilsen,. "Nuclear Powered Lighthouses," Oslo, 1992.
2. Information granted to the author in reply to an official inquiry to VNIITFA.
3. M.I.Rylov, M.N.Tikhonov. Problemy radiatsionnoi bezopasnosti…//Atomnaya strategiya, St Petersburg, N1(6) June 2003, p. 32. (In Russian).
4. Report on the activities of GAN in the field of nuclear and radiation safety in 1998. Moscow, 1999, p. 72. (In Russian) See also M.I.Rylov, M.N.Tikhonov. Problemy radiatsionnoi bezopasnosti…//Atomnaya strategiya, St Petersburg, N1(6) June 2003. P. 32. (In Russian).
5. www.vniitfa.ru/_Products/RadioNuclIst/RadioNuclIst.htm (In Russian).
6. Y.V. Klyuyev [head of the SHS of the Transportation Ministry. Prodolzhayem razgovor…// Yakutia, Yakutsk, No. 59, April 1st 2000 (In Russian).
7. Agapov’s statements are a reply to the author’s inquiry about RTG decommissioning at a Minatom conference in St Petersburg, September 1st 2003.
8. M.I.Rylov, M.N.Tikhonov,. Problemy radiatsionnoi bezopasnosti…//Atomnaya strategiya, St Petersburg, N1(6) June 2003, p. 32. (In Russian).
9. Information confirmed in reply to the author’s official inquiry to VNIITFA.
10. Y.V. Klyuyev head of the SHS of the Transportation Ministry, Prodolzhayem razgovor…// Yakutia, Yakutsk, No. 59, April 1st 2000 (In Russian).
11. The Russian Ministy of Natural Resources. The State Report of 1999. www.ecocom.ru/Gosdoklad99/Part1-7.htm (In Russian).
12. The Russian Ministy of Natural Resources. The State Report of 1998. www.mnr.gov.ru/BUTT_R/5/2/Gosdoklad98/Part1-7.htm(In Russian).
13. Information partly taken from: A.M.Agapov, G.A. Novikov, Radiologichesky terrorism… www.informatom.ru/rus/safe/vena/Vena.asp (In Russian), and M.I.Rylov, M.N.Tikhonov. Problemy radiatsionnoi bezopasnosti…//Atomnaya strategiya, St. Petersburg, N1(6) June 200,. p. 32. (In Russian).
14. Information granted to the author in reply to an official inquiry to VNIITFA.
15. A report on the activities of GAN’s branch of the Far Eastern Interregional Territorial District in the field of nuclear and radiation safety regulation at the sites of application of atomic energy, first half of 2003 www.gan.ru/dvmto/otchet_1_2003.htm (In Russian).
16. The Russian Ministy of Natural Resources. The State Report of 1997. web.archive.org/web/20020223084209/http://www.ecocom.ru/arhiv/ecocom/Gosdoklad/Section29.htm(In Russian).
17. M.I.Rylov, M.N.Tikhonov. Problemy radiatsionnoi bezopasnosti…//Atomnaya strategiya, St. Petersburg, N1(6) June 2003, p. 32 (In Russian).
18. Information provided by the environmental NGO Kaira-Club, Chukotka region, www.kaira.seu.ru/kv/kv0902p2.htm (In Russian) See also: Report on the activities of GAN… 1997. Moscow, 1998, p. 72 (In Russian).
19. GAN Statement http://www.gan.ru/info82.htm (In Russian).
20. Information provided by the environmental NGO Kaira-Club, Chukotka region, www.kaira.seu.ru/kv/kv0902p2.htm (In Russian), see also: M.I.Rylov, M.N.Tikhonov. Problemy radiatsionnoi bezopasnosti…//Atomnaya strategiya, St. Petersburg, N1(6) June 2003, p. 32 (In Russian).
21. Government of Sakha Republic (Yakutia), the Ministry for the Protection of the Environment. The State Report "On the state of the environment and activities in the field of nature preservation in the Republic of Sakha (Yakutia) in 2001," Yakutsk, 2002, www.sterh.sakha.ru/gosdoklas2001/zakl.htm(In Russian).
22. Information on the violations of licencing terms and the violations of laws, federal norms and regulations in the use of atomic energy, information on the actions taken against the violators, third quarter of 2002 web.archive.org/web/20021024163030/http://www.gan.ru/dvmto/nlic-3.2002.htm(In Russian).
23. N.R.Kuzelyov. A review of “Problemy radiatsionnoi bezopasnosti…”//Atomnaya strategiya, St. Petersburg, N1(6) June 2003, p. 33 (In Russian).
24. Agapov’s statements are quoted as a reply to the author’s inquiry about RTG decommissioning at a Minatom conference in St Petersburg, September 1, 2003.
25. N.R.Kuzelyov. A review of "Problemy radiatsionnoi bezopasnosti…"//Atomnaya strategiya, St Petersburg, N1(6) June 2003, p. 33 (In Russian).
26. Ibid.
27. Ibid.
28. The Murmansk Regional Administration, Press release of 17.11.2003 No. 386 (In Russian). See also: Igor Kudrik, Rashid Alimov, Charles Digges. Two strontium powered lighthouses vandalised on the Kola Peninsula. http://www.bellona.no/en/international/russia/navy/northern_fleet/incidents/31767.html
29. Ibid.
30. Cape of Pihlisaar: 59°47’N 28°10’E.
31. Boris Karpov. Po tolstomu l’du. //Nevskoe Vremya, St. Petersburg, March 22, 2003, nevskoevremya.spb.ru/cgi-bin/pl/nv.pl?art=142016251 (In Russian).
32. GAN Statement www.gan.ru/4upr_spravka_2_2003.htm(In Russian).
33. The author’s interview with head of Radon Alexander Ignatov, April 2003; press release of the NGO Zelyony Mir, www.greenworld.org.ru(In Russian).
34. Decree issued by the governor of the Leningrad region No. 309-pg of June 20th 2000, www.lenobl.ru/main2.php3?section=government4_32#Pril3 (In Russian).
35. GAN Statement www.gan.ru/dvmto/stat2.htm (In Russian).
36. Inventory of accidents and losses at sea involving radioactive material. IAEA-TECDOC-1242, IAEA, Vienna. 2001.
37. Marina Plechikova. Gotovitsya expeditsiya…// Svobodny Sakhalin, Yuzhno-Sakhalinsk, April 30th 2003 (In Russian).
38. Mikhail Gorbunov. Mstitel okhotskogo morya…// Rossiyskaya Gazeta, July 30th 2003. See also eco-pravda.km.ru/sreda/rg30il3.htm (In Russian).
39. Information granted to the author in reply to an official inquiry to VNIITFA.
40. V.V.Dovgusha, M.N.Tikhonov, Radiatsionnaya obstanovka na Severo-Zapade Rossii. St Petersburg, 2000 (In Russian).
41. Radiatsiya v tsentre Dushanbe. //"Azia Plus", Dushanbe, April 2002 ecoasia.ecolink.ru/data/2002.HTM/000147.HTM (In Russian).
42. Information granted to the author in reply to an official inquiry to VNIITFA.
43. Marina Plechikova. Sakhalin i Kurily mogut…//Svobodny Sakhalin, Yuzhno-Sakhalinsk, No. 51(781), December 19th 2002 (In Russian).
44. See, for example, Anna Seleznyova. Radiatsionnaya lovushka…// Ekologiya i Pravo, No. 7, June 2003, P. 18 ( www.ecopravo.info); also see: Yevgeni Izyurov. Khronika luchevoi bolezni. //Vladivostok, N1330, 26th March 2003 ( www.vladnews.ru/magazin.php?id=11&idnews=9509&current_magazin=1330). (In Russian).
45. web.archive.org/web/20030423022347/http://lugar.senate.gov/nunnlugar.htm
46. Report by Minister of Atomic Energy Alexander Rumyantsev at the IAEA conference "Security of Radioactive Sources," Vienna, Austria. March 11th 2003, www.iaea.org/worldatom/Press/Focus/RadSources/statement_rus.pdf
47. IAEA conference "Security of Radioactive Sources," Vienna, Austria. March 11th 2003. Findings of the Chair, www.iaea.org/worldatom/Press/Focus/RadSources/PDF/findings.pdf
48. Agapov’s statements are quoted as made in reply to the author’s question about RTG decommissioning at a Minatom conference in St Petersburg, September 1st 2003.
49. Information granted to the author in reply to an official inquiry to VNIITFA.
50. Government of Sakha Republic (Yakutia), the Ministry for the Protection of the Environment. The State Report "On the state of the environment and activities in the field of nature preservation in the Republic of Sakha (Yakutia) in 2001," Yakutsk, 2002, www.sterh.sakha.ru/gosdoklas2001/zakl.htm(In Russian).
51. Yakutia. 38 iz 75 radioizotopnykh generatorov podlezhat utilizatsii. Regnum News Agency, January 20th 2003 12:04 (In Russian).
52. N.R.Kuzelyov. A review of "Problemy radiatsionnoi bezopasnosti…"//Atomnaya strategiya, St. Petersburg, N1(6) June 2003, p. 33 (In Russian).
53. The Murmansk Regional Administration. Statement on the international cooperation of November 22d 2000, www.murman.ru/ecology/comitet/report99/part7_5.html(In Russian).
54. Thomas Nilsen. Nuclear Lighthouses to be Replaced. www.bellona.no/en/international/russia/nuke-weapons/nonproliferation/28067.html, Oslo, Febrary 2d 2003.
55. Pyotr Bolychev. Bolshe kron…// Murmansky Vestnik. Murmansk. April 12th 2003 (In Russian).

Rashid Alimov

rashid@ecoperestroika.ru