AND CENTRAL EUROPE
Lynne C. Myers
Science and Technology Division
A. RBMK Reactors
B. VVER Reactors
IN CENTRAL AND EASTERN
INTERNATIONAL AID FOR IMPLEMENTING
AND CENTRAL EUROPE
of the former Soviet Union and other political changes in eastern and
central Europe have opened up the area to closer scrutiny than was previously
possible. Because of the accident at Chernobyl, nuclear power is one of
the subjects that western nations have had a great deal of interest in
exploring. The former Soviet Union designed and/or helped build more than
60 civilian reactors in the region. Most of these reactors follow one
of two distinctly different designs: the VVER, or pressurized water reactor
series; and the RBMK, which is a graphite-moderated, multi-channel reactor
(the so-called Chernobyl type). In addition, there are two fast-breeder
reactors and four graphite-moderated boiling water reactors for combined
heat and power in operation in Russia. These last two designs are not
widely distributed and so are not discussed in detail in this report.
As noted above, the safety
of Soviet-designed reactors has been of great concern around the world
since the catastrophic events at Chernobyl in 1986. This paper will briefly
describe the technology involved. It will also examine the main safety
concerns, both technical and organizational, associated with each reactor
type. In addition, the paper will review the nuclear power programs in
the new countries emerging from the former Soviet Union and its satellites
and discuss the international efforts underway to address the most pressing
A. RBMK Reactors
A loose translation of the
acronym RBMK is "very large, tube type reactor." This design
originated from the early Soviet military reactors used to produce plutonium
for weapons. The first generation of reactors, designed for plutonium
production only, used graphite as the neutron moderator, with the fuel
cooled by ordinary water. In the second generation, the fuel was enclosed
in zirconium alloy pressure tubes, allowing the water to operate at high
pressure and high temperature.
In this Soviet design, the
coolant water itself is allowed to boil, and the resulting steam is fed
directly to the steam turbines, which then power generators, producing
electricity. The success of the early 100 and 200 MW military reactors
led the Soviets to develop a 1,000 MW "commercial" RBMK
reactor. The first two units, built near Leningrad, came on-line in 1973
The RBMK reactor consists
of a large cylindrical array of graphite blocks which act as the neutron
moderator and through which 1600 zirconium alloy pressure tubes pass vertically.
The nuclear fuel, which is enriched uranium dioxide, is contained in the
pressure tubes and the ordinary water, which acts as the coolant, is pumped
upwards through them. The water absorbs heat from the nuclear reaction
and, as a result, some of it boils, forming steam. The steam and water
mixture then passes into the steam drums where it is separated, with the
steam being channelled off to the turbines, which then drive the generators.
The reactor is controlled
by a large number of control rods, which alter the rate of the nuclear
reaction that takes place. As more rods are inserted into the reactor,
the rate of fission slows down. The rods are the main safety feature of
the RBMK, being used to shut down the reactor completely if necessary.
However, in some circumstances, the shutdown rate is not adequate. The
inappropriate operation of the reactor at Chernobyl during a scientific
experiment created just such a situation. The safety system could not
react fast enough to prevent the reactor from going out of control, with
disastrous consequences. Subsequent modifications, including speeding
up the shutdown system, redesigning the fuel and adding fixed neutron
absorbers appear to have largely overcome this particular fault.
Unlike most western-designed
nuclear reactors, the RBMK design does not include a concrete containment
structure which would act to prevent the dispersion of radioactivity following
an accident. The size and the layout of the existing RBMK plants precludes
retrofitting such structures and so this problem remains.
B. VVER Reactors
The second type of soviet-designed
reactor is the VVER type. This acronym stands for "water-water reactor,"
since ordinary water acts as both the neutron absorber (as opposed to
graphite in the RBMK type) and as the fuel coolant. This reactor type
is very similar to the PWRs (pressurized water reactors) used in many
western countries. It has the same origin as well, having first been developed
for use in nuclear-powered submarines.
The prototype land-based
VVERs had power outputs of 210 MW and 365 MW. Subsequently, the design
was standardized at a rated output of 440 MW. The first VVER reactors,
model 230, were built in the 1960s; after 1970 they were superseded by
the second generation, Model 213. A third generation of "small"
(440 MW) reactors followed, as did the 1000 MW VVER 320 series. Each subsequent
series added improved safety features, but, as discussed elsewhere in
this report, concerns remain.
As was noted above, the
VVER reactor is very similar to the pressurized water reactors common
in western countries other than Canada. The reactor consists of a large,
very thick-walled pressure vessel which contains the reactor fuel and
ordinary water. The fuel used in the VVER reactor is enriched to about
four times the natural level of uranium-235. The water acts as both a
neutron moderator, which sustains the nuclear reaction, and as the coolant,
which removes the heat of the reaction from the vessel. The hot water,
which is also under pressure in the vessel, leaves the vessel and passes
through heat exchangers. The heat is used to boil water, producing the
steam to drive the steam turbines and subsequently the generators. The
cooled water is then recirculated through the pressure vessel to continue
Various technical and organizational
problems associated with the nuclear power program in the former Soviet
Union (FSU) and its satellites have given rise to serious concerns about
the safety of the reactors operating in that part of the world. Since
the break-up of the FSU, experts from both within Eastern Europe and from
the west have had the opportunity to work closely with Soviet scientists
to assess the basic safety deficiencies and to identify possible remedial
action. Western input has been on both a bilateral and a multinational
basis, with the International Atomic Energy Agency playing a leading role
in many studies. The results of these numerous investigations give a fairly
clear picture of the situation.
One joint German-Russian
study outlined the root causes of the safety deficiencies very succinctly.(2)
According to this report, four main factors have contributed to the safety
problems in Soviet-designed nuclear reactors. The first factor is the
Soviet authorities' belief in the strength of their technology. In designing
their reactors, the Soviets took into account only the most likely accidents
and included safety systems to address only these. In western technology,
even accidents with a very remote chance of happening are analyzed and
safety systems for handling them are incorporated in the design.
A second difficulty arises
from the strong reliance of Soviet technology on the human element. Western
systems are more fully automated, recognizing the possibility of human
error in the operation of such complex technology. In the Soviet design,
personnel on duty in the control room are able to intervene in most aspects
of reactor operation. For example, as happened at Chernobyl, control-room
personnel can easily disconnect the main safety control system. This is
not the case with western-designed reactors.
delay" in the Soviet economy has also led to a number of safety-related
problems. This is particularly true in the areas of instrumentation and
control, electronics and computing. Shortcomings in these areas, for example,
made it difficult for the Soviets to include advanced automation concepts
in their reactors. This led to even more reliance on human intervention
in the operation of reactors and made it impossible for the Soviets to
build sophisticated training simulators that would have improved the technical
training of operators and given them the chance to perfect accident response
The fourth problem identified,
and echoed in other reports, was the lack of "corrective criticism."
Within the Soviet government structure, one agency or department had responsibility
for all aspects of nuclear power development; there was no independent
organization to verify the safety of Soviet-designed reactors. In the
newly emerging countries of Eastern Europe a great deal of effort is being
made to ensure that the necessary regulatory framework for the safe operation
of nuclear power stations is put into place.
A number of very detailed
technical reports on the safety of Soviet-designed reactors have been
prepared in recent years. The International Energy Agency has been the
coordinating agency for many of these efforts, having initiated a program
in 1990 designed to help the countries of eastern Europe and the FSU assess
the safety of the first generation VVER 230 reactors. The objectives of
the program were: to identify major design and operational issues; to
establish an international consensus on priorities for safety improvement;
and finally, to provide assistance in their implementation.(4)
The international community
focused first on the VVER 230 series, despite the grave concerns about
the safety of RBMK technology that arose in the wake of the Chernobyl
accident. Most experts felt that the RBMKs were so inherently unsafe that
their use should and would quickly be phased out. Only the most urgent
safety improvements were foreseen, to keep them operating until they could
be replaced. Attention was focused on the VVER-230, which, though also
considered unsafe, was likely to be in operation longer and therefore
perhaps more worth upgrading. As subsequent sections of this paper point
out, however, economic circumstances mean that RBMK reactors will continue
in operation longer than once anticipated. The search for means of ensuring
their longer-term safety has therefore come to the fore more recently.
In fact, in 1992, the IAEA program was extended to cover the safety of
RBMK reactors as well.(5)
The IAEA report on the safety
of the VVER-230 is very detailed and technical. Only the highlights will
be given here as illustrative of the problems faced. Appendix 1 provides
a more detailed list of the generic safety concerns for these reactors.
As already noted, of the three generations of VVERs, this model is seen
as having the most safety problems and therefore requiring the most urgent
One of the major concerns
related to the VVER-230 is the lack a containment structure, such as the
familiar concrete dome that encloses the CANDU and other western reactors,
which would limit the spread of radioactive contaminants in the event
of an accident. A second shortcoming is the insufficient level of "redundancy"
(back-up) in the safety systems. In addition, there is no provision for
response to common cause failure of the electrical system supplying the
safety equipment or the reactor itself. The limited core cooling capacity,
insufficient on-site fire protection and an inadequate instrumentation
and control system were also identified as problems needing urgent attention.(6)
In addition to the technical
safety concerns, a number of major operational shortcomings were also
identified in the IAEA report. For example, experts felt that there was
not an effective management structure for identifying and correcting safety
issues at the nuclear power stations. Furthermore, they identified problems
with the equipment at the plants. It was not always maintained in an appropriate
manner. Operating procedures were not always well or completely documented,
or their use was inadequately enforced. The lack of proper training, especially
in the absence of simulators, was also noted as a concern, as were inadequate
inspection and regulatory enforcement.(7)
A number of experts have
stated that the cost of improving the safety of VVER-230 reactors for
long-term operation is too high.(8) They recommend retrofitting instead, with
a view to keeping these plants in operation only as long as is absolutely
required for energy needs.(9) As in the case of the RBMK reactors, however,
the energy demands and the economic conditions in the countries using
this reactor design may mean that the Model 230s stay in use longer than
western experts would like.
The IAEA assessment of second
generation VVERs, model 213, shows that they include significantly more
safety features than the older model and so are of less immediate concern.
Nonetheless, a number of measures need to be implemented to allow them
to operate safely for their planned lifetimes. The list of urgent measures
includes installation of western instrumentation and control to partially
replace existing technology; installation of a residual heat removal system;
upgrading of the emergency power supply; improved fire protection measures;
personnel training; completion of operation, maintenance and inspection
manuals and more complete accident analyses.(10)
A number of medium-term measures are also identified that would add still
more sophisticated safety features.
By all accounts, the VVER
1000, which is the newest, most advanced Soviet design, includes many
of the safety features found in western pressurized water reactors. As
a result, no major improvements are seen as necessary, although a number
of retrofit measures are suggested. For example, the basic design of the
VVER 1000 makes it very important to maintain careful minute-by-minute
control of operating conditions. To ensure that operators are fully aware
of what is happening in the reactor core, it is recommended that modern
western instrumentation and control systems be installed. Other recommendations
deal more with non-technical details such as improvements to operator
training and to manuals dealing with operation, maintenance and control.(11)
As already noted, the safety
of RBMK reactors is still of concern, as the estimated length of time
during which they will remain operational appears to be increasing. It
should be noted, however, that since the accident at Chernobyl, a significant
number of changes have already be made in the operating RBMKs and in fact
a number of new RBMKs have come into operation. These new reactors incorporate
the safety improvements that have been backfitted on to the older units
and so should be safer than their predecessors. The RBMK design has evolved
over the years, even before Chernobyl, and so not all units will present
the same problems. Concerns relate primarily to the six oldest RBMKs:
two units at each of three sites, Kursk and Smolensk in Russia, and Ignalina
The IAEA study on RBMK safety,
which was published in March 1993, reviews the safety improvements already
made to the RBMKs, and assesses their success. It also looks at the additional
measures still required to further improve the safety of these units.
In general terms, most of the changes already implemented address the
major design and operational problems of the RBMK that contributed to
the accident at Chernobyl. These included the large, inadequately monitored
power fluxes within the reactor core; the slow, and again inadequate,
response of the safety shutdown equipment; and the part played by human
Human error cannot be eliminated,
but with new administrative and operating procedures in place, the chances
of such error have been reduced. Also, there have been some technical
changes that make the safety system less prone to human error. For example,
in the original RBMK design, the operator could manually stop the reactor
by pushing a button and keeping it depressed until the reactor was completely
shut down. The button has been replaced by one that simply needs to be
hit once and will stay activated until shutdown.
New equipment that monitors
reactor core conditions every five rather than fifteen minutes has been
added and there have been improvements to the equipment controlling the
core physics. To address the shutdown problem, the control rods, which
are inserted into the reactor to slow and finally stop the chain reaction,
have been significantly altered. A new fast scram system (FSS), which
includes 21 to 24 fast acting control rods with a response time of just
2.5 seconds, has been added. Also, there are now more control rods
inserted from the bottom, as well as the top of the reactor, and their
response time has gone from 19 seconds down to 12 seconds.
Additional changes have
improved the reliability of electrical power supply to the safety systems;
improved the outside water supply for emergency use in the upgraded emergency
core cooling system; upgraded the fire protection systems; improved the
seismic resistance of the facilities; and added on-site, automated radiation
monitoring.(12) In at least one case,
the Leningrad 1 unit, all 1,693 fuel channels have been replaced to bring
them back to original design standards.(13)
Despite these significant
changes to the RBMK reactors, western experts remain concerned about their
safety. The IAEA report acknowledged the efforts made to date, but also
listed measures that are still necessary. A number of these relate to
the necessity for better data-handling equipment to ensure that operators
can keep up with the rapid changes occurring while the reactor is in operation.
Existing computer systems are characterized as being "overloaded,"
resulting in an inadequate data-processing capability. Experts still feel
that the plant safety is too dependent on operator actions, and recommend
further automation efforts. The replacement of existing instrumentation
and control systems is recommended as well. Those responsible for the
safety assessment of the RBMKs also note that they require more detailed
information from authorities in the countries concerned to complete their
assessment and make final recommendations.(14)
SOVIET-DESIGNED NUCLEAR POWER
IN CENTRAL AND EASTERN EUROPE
Table 1 provides details
of the location, size and model of Soviet designed reactors that are in
operation, or operable in eastern and central Europe. The situation in
each country, with regard to the current and future role of nuclear power
and to the nature of the problems being faced is different, and so will
be reviewed briefly.
Soviet-Designed Power Reactors in Operation or Operable: 1992
South Ukraine 1
South Ukraine 2
South Ukraine 3
Czech and Slovak
1 PWR = pressurized
LWGR = light water graphite-moderated
FBR = fast breeder reactor.
GBWR = graphite-moderated
boiling water reactor.
2 VVER models
V-179, V-230 and V-270 are first generation designs; model V-213 is
second generation; and models V-187, V-338 and V-302 are third generation
"small series" and V-320 third generation "large series."
3 Output reduced
by regulator for safety reasons.
boiling water reactor for combined heat and power.
5 These reactors
were shut down in 1989, but the Armenian government recently decided
to investigate recommissioning.
6 Also desalinates
80,000 m3 of water per day.
7 Four V-230
units were built at Greifswald in former East Germany, but they have
been shut down since reunification, due to safety concerns.
Ex-USSR," Nuclear Engineering International, August 1992,
p. 37; and Morris Rosen, "International Nuclear Safety Assistance
to Eastern Europe," Special Session, Nuclear Power in Eastern
Europe and CIS - An International Challenge? World Energy Conference,
Madrid, Spain, September 1992, p. 10-12.
In Russia, there are currently
28 nuclear power reactors at nine separate sites, with a total installed
capacity of some 19 342 MWe (megawatts electric). The 28 reactors include
11 of the RBMK type, with four each at Kursk and Leningrad and three more
at Smolensk. Twelve reactors are of the VVER, or pressurized water, design
and there is one fast breeder reactor at Beloyarsk. The final four reactors
are a unique design, being small graphite-moderated boiling water reactors
used for combined heat and power production, a technology not used anywhere
else in the former Soviet Union.(15)
For the country as a whole,
nuclear power accounts for about 11% of electricity generation; however,
on a regional basis its importance is considerably greater. For example,
in the St. Petersburgh area nuclear power provides 33% of all electricity,
and in the Moscow area it provides 22%. This regional dependency means
that western concerns about safety will not soon result in any nuclear
power plant closures. The country simply has no short-term options. In
fact, rather than contemplating shutting down any reactors, there are
five additional VVER 1000 reactors under construction in Russia, along
with the two heat-only reactors being installed in Voronezh. These six
reactors could be on-line by the year 2000. Plans are also in place for
two more fast-breeder reactors in the South Urals, but their construction
status is uncertain at this time.(16)
Local authorities have already
approved construction of additional reactors, as replacement for older
units, at the Kola, Novovoronezh and Leningrad nuclear complexes. The
1992 state investment program for the Russian Federation included plans
for three or four new nuclear power plants - anticipated to be at Kostroma,
Karelia, the Far-East and probably Rostov.(17)
Given the experiences of
the former Soviet Union with nuclear accidents, most notably at Chernobyl
and the more recent explosion at Tomsk, one may wonder why any of the
republics of the FSU still have such ambitious nuclear construction plans.
The answer is simply that they need the energy. Russia now generates 80%
of its electricity in aging oil-fired power plants and the production
of oil in Russia has been dropping at the alarming rate of 15% annually
in recent years. Add to this the fact that more and more of Russia's oil
is being sold in the export market for hard currency, and the fact that
the domestic price of oil has increased 300% in the past year, and the
attraction of nuclear-generated electricity becomes clearer. All the republics
of the FSU face similar problems and so for them also nuclear power will
continue to be a necessary part of the energy supply for the foreseeable
When it became an independent
country, the Ukraine took on the burden of looking after the Chernobyl
plant, site of the world's worst nuclear power plant accident. The government
of the Ukraine took over control of this and four other nuclear power
complexes from the former Soviet Ministry of Nuclear Power and Industry
in November 1991. As shown in Table 1, the Ukraine now has 14 power
reactors in operation. They have an installed capacity of 12,802 MWe and
provide 25% of the Ukraine's electricity.
The two units still operating
at Chernobyl, units 1 and 3, were scheduled to be shut down at the end
of 1993. However, like Russia, the Ukraine desperately needs the energy
they can produce. The country imports about 50% of its primary energy
needs, with 90% of those imports coming from Russia. Russia now demands
hard currency in payment for oil and gas, which Ukraine, with its economy
in virtual collapse, cannot provide. This dilemma led the Parliament to
reverse its decision to shut down the remaining Chernobyl reactors, and
to begin repairs to a third unit which had been out of service for two
years following a fire.(19) The Ukraine is so desperate for electrical power that
it has gone even further and lifted the moratorium on new nuclear plant
construction which had been imposed following the Chernobyl disaster.(20)
As a result of this policy change, three 1,000 MWe VVER reactors which
are nearly complete (one each at the Khmelnytsky, Rovno and Zaporozhye
sites) could be finished and come on line between 1993 and 1995, if the
necessary money can be found. It has been suggested by some that it may
be in the interests of the international community to provide loans to
complete these reactors, since they would have much higher safety standards
than the Chernobyl units that they could replace.(21)
With the dissolution of
the Soviet Union, the Ukraine was left to develop its own bureaucracy
for regulating and managing nuclear power. At the management level, the
power stations have been formed into a consortium, which, in turn, has
entered into contractual arrangements with agencies in Russia to secure
the services needed to keep the plants operating. There has been some
difficulty over Russian acceptance of spent fuel from Ukrainian reactors.
This issue is still unresolved but discussions are underway to set up
joint ventures to handle the problem.(22)
With regard to the Chernobyl
site, Moscow withdrew all financial support at the end of 1991. To fund
ongoing clean-up efforts, the people of the Ukraine are paying a big price
- a 12% tax on all citizens (no information is available as to whether
it is a consumption tax or an income tax, etc). Even this hefty tax, however,
falls short of raising the amount needed to clean up the aftermath of
the accident. In the last two years new agencies have evolved to oversee
the clean up work. The Ministry of Affairs of Population Protection from
the Results of Chernobyl (known as MinChernobyl) and the State Committee
for Nuclear Power are in the process of sorting out who has responsibility
for which aspects of the clean up; the latter feels it should have responsibility
for the remains of unit 4 and its sarcophagus and MinChernobyl should
look after only the cleaning up of the 43,000 square kilometre contaminated
zone. No matter what the outcome of this bureaucratic battle, MinChernobyl
has developed an action program to the year 2000, and has begun work on
The program has three main
aspects: radiation protection, which deals with the relocation of people
in the contaminated zone; social security, which addresses the health-related
problems of those affected by radiation or the fear of radiation contamination;
and finally the long-term program, which includes decontamination, waste
management, protecting water from contamination, and (at the moment) work
on the sarcophagus and unit 4. Clearly, the clean up and management of
the damaged reactor will be both costly and lengthy. Yet despite this
bitter legacy the Ukraine has no choice but to continue to rely on nuclear
technology for a significant proportion of its electricity production.
Lithuania operates two reactors
of the RBMK, or Chernobyl type, each of which is rated at 1,500 MWe. All
other RBMKs are only 1000 MW units. A third unit is partially completed
but construction has been halted for some time, and recently the government
announced its decision not to complete the unit. The station authorities
have been given permission to sell off the equipment that is no longer
The safety of the two operating
units is of great concern, especially to Sweden, on whose doorstep they
are located. As a safety precaution, the units have been derated to 1,250 MWe
each. Even so, they supply the majority of the country's electricity and
earn valuable foreign currency as 42% of Lithuania's electricity (from
all sources) is exported to Belarus. In fact, in early 1993 the percentage
of Lithuanian power supplied by nuclear power topped all countries in
the world at 88%. This percentage has grown gradually over the last few
years as electricity demand in the country has fallen and fossil fuel
plants have been shut down, in favour of operating the nuclear power stations
at full capacity. Lithuania has no indigenous energy resources and the
rising cost of importing oil, coal and gas from Russia is an important
factor in this situation.
As is the case in the region's
other newly autonomous republics, Lithuania was dependent on Russian operators
at its nuclear power plants. Since independence, however, the majority
of operators have become Lithuanian citizens and so the country has the
necessary technically trained people to keep the stations running efficiently.
In addition, the power station operators have negotiated arrangements
with Russia to ensure that a supply of nuclear fuel, spare parts and maintenance
services remains available to them.(25)
The government has also given approval for the construction of a spent
fuel storage facility at Ignalina.
With such a large dependence
on nuclear power, it is not likely that the two Ignalina units will soon
be decommissioned and they have therefore received international attention
aimed at upgrading their safety features. As outlined elsewhere in this
paper, Sweden has established a bilateral program with Lithuania which
has already seen about $7 million (U.S.) invested in safety-enhancing
changes to the reactors.(26)
There are two first-generation
VVER reactors in Armenia, but neither has been in operation since 1989,
when they were damaged by massive earthquakes. The closure of the nuclear
power plants, which used to supply 25% of the country's electricity, has
contributed to the severe energy shortages in Armenia, to the point that
electricity use is rationed to just a few hours per day.
The continuing war with
Azerbaijan has resulted in the cutting of oil and gas pipelines between
the CIS and Armenia, which worsens the already desperate energy situation.
In an attempt to address the staggering shortages of energy, the Armenian
government has approached Russia for aid in re-commissioning the two damaged
reactors, and experts from France are analyzing the safety improvements
which can be made before re-starting one or both reactors. Plans have
also been put forward for the construction of a further 2,000 MW of nuclear
capacity by the year 2005. Neither of these options seems likely to be
implemented, however, as long as the war goes on. Russia would not want
to antagonize Azerbaijan, and in any case probably does not have the financial
capability to be of much help.(27)
The international community
does not want to see these reactors re-started, and since January 1992
the U.S. has been supplying aid, much of it in the form of fuel, to help
Armenia through its energy crisis. However, the fuel must be trucked in
from a post in neighbouring Georgia, where the civil war often results
in disruption of even these supplies.(28)
Nuclear power provides more
than 30% of the electricity generated in Bulgaria. A number of factors,
including the poor state of the country's fossil-fuelled plants, the low
quality and reduced production from domestic coal mines, and the unreliability
of electricity imports from Russia and the Ukraine, dictate that nuclear
power will continue to play a leading role in the energy scene.(29)
All six of the country's
reactors are located at Kozloduy, on the Danube River about 220 km north
of Sofia. The complex includes four 440 MWe first generation VVER 230
reactors and two, more modern 1,000 MWe VVER 320s. The oldest two units
began operation in 1974-75, the next two in 1981-82 and the larger units
in 1988 and 1992. The four older units have been a focus of international
concern since this model is seen as the most dangerous Soviet design still
in use, and because of the poor maintenance record at the site.
When political changes in
Eastern and Central Europe opened Bulgaria's nuclear program to international
scrutiny, the IAEA (International Atomic Energy Agency) studied the safety
of the VVER 230 reactors and recommended that at least two of the units
be closed down immediately. The Bulgarian government refused to do this,
citing the serious energy supply problems noted above. Given this refusal
and the concern over the safety of these reactors, the Kozloduy complex
became the first to receive financial support from the internationally
funded nuclear safety account being managed by the European Bank for Reconstruction
and Development (discussed elsewhere in this report).(30)
This funding, and the upgrading
it will support comes after a two-year program involving a number of European
Community members in which operators were given help in basic "housekeeping"
(i.e., routine maintenance and equipment testing) at the site. This program
was necessary just to bring the station up to its original, albeit inadequate,
safety standards. Operators were also encouraged to improve their "safety
culture" and operating practices by being twinned with operators
at a French nuclear power station.(31)
Bringing the reactors at
the Kozloduy complex up to international standards will cost hundreds
of millions of dollars, according to most estimates. The international
community will certainly be called on to provide most of the funding since
Bulgaria shares the desperate financial situation of other former communist
The former Czechoslovakia,
which has now separated into the Czech Republic and Slovakia, depended
on nuclear power for about 28% of its electricity. The Czech Republic
now operates the four VVER 213 reactors at Dukovny while Slovakia is responsible
for the four first generation VVER 230 reactors at Bohunice, as well as
four nearly completed VVER 213s at Mochovce.(32)
The reactors in these two
countries evoke many of the same safety concerns as do all other older,
Soviet-designed reactors, although for the reactors at Dukovny, there
is less concern, since the Czechs insisted on making most of the equipment
themselves, rather than using less reliable Soviet equipment. The licences
for the Bohunice 1 and 2 were changed in 1990 so that they could continue
to be operated from 1992 to 1995 only if a total of 81 measures were introduced
to improve safety and efficiency of operation. The measures are being
implemented progressively and are on schedule. Operation beyond 1995 will
require major reconstruction of the units, which the government had agreed
would happen only if costs remained between U.S. $200 and $400 million.
More recently, safety regulators in Slovakia recommended that the necessary
upgrading for post-1995 operation go ahead, with no mention of the cost
limitation.(33) International aid will be forthcoming
through the CEC (Commission of European Communities) technical assistance
program (the PHARE Program).(34)
There is also a great deal
of concern about the mounting stocks of spent fuel. In the past, all spent
fuel was shipped to the Soviet Union for reprocessing and disposal. New
spent fuel storage facilities are urgently needed, and a dry storage facility
at Dukovny is being planned. In the longer term, France and Britain are
both urging the new governments in the Czech and Slovak Republics to ship
their fuel to the West for reprocessing.(35)
In terms of increasing energy
demand, a recently completed government study in the Czech Republic forecast
that the country would require 2,000 MW of additional electrical capacity
by the year 2010. The current government in that country has expressed
the opinion that completion of the two partially built VVER 1000 reactors
at Temelin would be the cheapest way of providing that power. The Temelin
site is in southern Bohemia near the Austrian border, and the government
of Austria does not want to see these Soviet designed reactors brought
into use. As an alternative they have suggested cooperation in developing
other sources of electricity. Nuclear opponents within the country are
arguing that an ambitious electricity conservation program could reduce
current consumption by as much as 50% and make completion of the reactors
unnecessary. No final decision on this question has been reached.(36)
Like many other former Soviet
satellites, Hungary uses nuclear reactors designed and built by Soviet
experts. Unlike most of those other countries, however, there is a high
degree of input from Hungarian engineers and the country therefore has
an indigenous nuclear industry. As a result of this local input, the four
VVER 213 reactors at Paks are viewed by western experts as well built
and well run.(37) In fact, at the end of 1990, units 2
and 4 were ranked among the world's top ten reactors with cumulative (lifetime)
load factors of 88.9% and 86.5% respectively. Units 1 and 3 are rated
at 81.2% and 85.8%. The load factor is a measure of reliability of the
The exceptional performance
of the Paks reactors can also be attributed to the emphasis which the
Hungarians put on training and retraining of personnel. Unlike many other
central and eastern European countries, Hungary has invested in a nuclear
power plant simulator. Operators all receive 80 hours of simulator retraining
every year, including accident management training. The simulator is also
used to test emergency procedures and to verify changes in operating procedure.
The reactors have been continually
upgraded over the years since they came on-line (between 1983 and 1987).
For example, there is now a computerized environmental monitoring system
in place around the Paks complex. Also, the original, Soviet-designed
instrumentation and control system has been replaced by one designed in
Hungary. There is an active national research program to continue upgrading
these stations. The program focuses on accident prevention; severe accident
analysis; emergency preparedness; regulatory control and supervision;
and international relations and public acceptance.(39)
Hungary now gets about 50%
of its electricity from nuclear power. Future peak demand is forecast
to increase by 1,000 MW by the year 2000, and will likely be met by combined-cycle
or gas powered co-generation facilities. Over the same time frame an additional
base load plant will also be required and nuclear power is being considered,
along with coal-fired generation. Hungary is seeking bids for any additional
nuclear plants from several western countries, including France, Germany,
Canada and the U.S.(40)
AID FOR IMPLEMENTING
The problem of safety in
eastern and central Europe's nuclear power stations has been of concern
to countries around the world since the accident at Chernobyl. The need
for urgent action to address these concerns was voiced in many international
forums, including the 1991 World Economic Summit in London, the Lisbon
European Council and the G-7 Summit in Munich in 1992.(41) Because of its geopolitical, historical and economic
position, the European Community feels that it has an important role to
play in providing assistance to its neighbours in the former Soviet Union
and other east European countries to improve the safety of their reactors.
The EC has therefore developed two programs of assistance. One, known
as the PHARE program, is aimed at central and eastern European States.
The other, the TACIS program, is for the states of the ex-USSR.
Assistance under both programs
covers all aspects of safety of nuclear installations. It includes aid
directly to the plant operators as well as to any organization, including
the regulatory authorities, which play a role in assuring their safety.
There are three basic steps to the plan. First there is to be a thorough
evaluation of the design, operation and maintenance practices of nuclear
power plants. The second stage involves establishing a plan for retrofitting
plants and the third phase is the performance of all analyses and studies
needed to support the implementation of the necessary changes.(42)
An essential part of the EC plan is to support, not duplicate, any efforts
in these areas by the IAEA. All groups involved in providing aid agree
that the monetary needs are so great that close cooperation to avoid any
overlap is absolutely essential.
The PHARE program started
in 1990 and now covers work in Poland, Hungary, Czechoslovakia, Bulgaria,
Rumania and Lithuania (not all of whom have Soviet-designed reactors,
but do have nuclear safety issues to deal with). Total funding under this
program for 1990 and 1991 amounted to ECU 20.5 million with 12.7 million
going to Bulgaria; 7 million to Czechoslovakia, 0.5 million to Lithuania;
and 0.3 million for Poland.(43) The
large amount dedicated to Bulgaria reflects the concern over the serious
safety problems at the Kozloduy plant, considered by most western experts
as the most dangerous Soviet-designed reactor. A further ECU 3.5 million
was set aside for continuing work at Kozloduy for 1992. Another ECU 20 million
went to other countries in 1992.(44)
The TACIS program of technical
assistance to the states of at the former Soviet Union, began in 1991
and in that year funding for nuclear safety work was set at ECU 54.5 million.
This budget was divided between measures to improve the operational safety
of the different designs of VVER and RBMK reactors, and measures to strengthen
the regulatory authorities in the new states. The funding for 1992 was
roughly the same. While representing a significant contribution to identifying
what needs to be done, it must be recognized that considerably larger
sums of money will be required for the actual upgrading work to be completed.(45)
The 1992 Munich G-7 Summit
acknowledged this need for an international fund, to which the countries
present at the summit agreed to contribute. It was not until early in
1993 that the fund actually got off the ground. It will be administered
by the European Bank for Reconstruction and Development (EBRD) with decisions
for financing being made by a steering committee representing the donor
countries.(46) Pledges to the fund
for 1993-95 are as follows: France - ECU 40 million; Germany - ECU 40
million; Japan - ECU 4 million; UK - ECU 10 million; Italy - ECU
10 million; U.S.A. - ECU 1.5 million.(47)
In addition to these multilateral
programs, Canada, Sweden, Finland and the U.S. have bilateral agreements
related to nuclear safety. Canada has committed Cdn. $30 million
which will be used to fund part of the international RBMK safety review,
examine the potential use of Russian hardware at the Cernovoda complex
in Rumania and help in the establishment of an environmental centre in
Russia. Sweden is involved in the RBMK safety review and is funding a
safety assessment of the Ignalina 2 unit. This contribution is approximately
U.S. $10.5 million.
Finland is contributing
about U.S. $ 6.6 million to two projects. One involves the Kola plant
in Russia, where Finland will use experience with the VVER design at Loviisa
to improve operational safety. Finland is also involved with part of the
international RBMK safety efforts at Leningrad, where it is assessing
the probability of fires and how to limit their consequences and looking
at the reliability of certain reactor components.
The United States has a
complex series of bilateral programs which provided U.S. $3.2 million
to Eastern European projects in 1991, including work at Kozloduy and a
number of training programs. For 1992, U.S. $4.85 million was allocated
by the U.S. Department of Energy, the Nuclear Regulatory Commission and
several private companies (Bechtel/Electrotek) again for a variety of
programs including improvements in operational safety at Bohunice in the
Czech Republic and at Kozloduy in Bulgaria, as well as for more training
programs. Also in 1992, the U.S. contributed U.S. $22 million to Russia
and the Ukraine for help in a number of areas including completing safety
analyses, training regulators, improving fire protection, assisting with
programs to handle wastes, spent fuel and other nuclear materials, etc.(48)
The opening of the former
Soviet block countries to outside scrutiny gave western experts unprecedented
access to details of nuclear power programs in that part of the world.
What they found is not particularly reassuring. Assessments of the safety
of many of the older nuclear power plants have revealed some alarming
technical and operational problems. International action to help these
new countries assess and deal with these problems has been slowly gathering
Many of the necessary assessments
have now been completed and the international funding mechanisms are in
place. However, economic conditions and energy supply problems are making
it difficult for the newly emergent countries to meet western expectations
for upgrading, shutting down and/or replacing the most dangerous reactors.
Clearly the effort to enhance the safety of existing nuclear power plants
will be a lengthy and a costly one. Given the consequences of failure,
however, there is little choice but for the international community to
continue to work closely with the countries of the former Soviet Union
and its allies.
THE SAFETY OF NUCLEAR
IN CENTRAL AND EASTERN EUROPE
AN OVERVIEW AND MAJOR
FINDINGS OF THE
IAEA PROJECT ON THE
SAFETY OF VVER 440 MODEL 230 NUCLEAR POWER PLANTS
Atomic Energy Agency (1993), p. 13-14.
2.3. Study of Generic
The Secretariat has started
to prepare a series of documents on generic VVER-440/230 safety issues,
the aim being to clearly identify the work still required in order to
resolve the issues identified in the IAEA Project. It will also provide
information on the work already performed or underway in other countries
to avoid unnecessary duplication of work.
The following is a complete
listing of generic safety issues and their underlying safety concerns:
- Applicability of Leak Before Break
Because the VVER 440/230
plants have a very limited capacity to cope with primary circuit breaks,
the detection of leaks before catastrophic failures of the primary coolant
boundary is most important. Applicability of the leak-before-break concept
needs to be established.
- Reactors Pressure Vessel (RPV) Embrittlement
The safety of RPV subject
to radiation embrittlement needs to be resolved. Conclusions of studies
to estimate the temperature at which the steel becomes brittle (Nil
Ductility Temperature), effectiveness of the method used to recover
the vessel material properties (annealing) and rate of embrittlement
after annealing should be compiled.
- Instrumentation and Control (I&C)
Review of I&C logic
and set points is required. Information to control room operators is
poor and means of processing information are also poor and need to be
A comprehensive accident
analysis using modern computer codes is required. A broad spectrum of
pipe breaks and transients should be analyzed including confinement
response and estimation of radiological consequences when applicable.
Procedures for normal
operation and emergency conditions need to be developed, validated and
operators should be trained to use them.
Improved operators training
is required including accident management. Development and use of simulators
and modern training material is needed.
- Probabilistic Safety Assessment (PSA)
Plant specific PSAs would
be required to evaluate backfitting options. The level of detail of
the PSA should be defined consistent with the intended use of the PSA
Qualification of confinement
needs to be addressed including evaluation of structural strength, testing
of venting flaps and tightness.
The impact of system modifications
should be assessed, in particular with reference to safety injection
and spray systems, service water and feedwater system. Electric power
supply and actuation signals to these systems should also be considered.
A study of fire protection
including fire detection and fire fighting capabilities is needed. Design
weakness regarding lack of physical separation and diversity should
also be addressed.
Assessment of seismic
safety margins and evaluation of programs underway to enhance seismic
protection is needed.
A review of qualification
of sensors, actuators and other electrical and mechanical equipment
under accident conditions is required. Special attention to environmental
conditions following an accident is needed.
A Safety Analysis Report
does not exist for VVER 440/230 NPPs. Information available is scarce
and should be completed and extended to form a comprehensive safety
Information for this section provided by Government Corporate Relations,
Atomic Energy of Canada Limited, November 1993.
A. Birkhofer, "Root Causes of Safety Deficiencies," Paper No. 4,
Special Session on Nuclear Power in Eastern Europe and the CIS - An International
Challenge?" World Energy Conference, Madrid, Spain, September 1992.
International Atomic Energy Agency (IAEA), "Safety Assessment of
Proposed Improvements to RBMK Nuclear Power Plants," Report of the
IAEA Extra-Budgetary Programme on the Safety of RBMK Nuclear Power Plants,
Vienna, March 1993, Foreword.
International Atomic Energy Agency, "The Safety of Nuclear Power
Plants in Central and Eastern Europe," An Overview and Major Findings
of the IAEA Project on the Safety of VVER Model 230 Nuclear Power Plants,
Vienna, 1993, p. 1.
Ibid., p. 11.
Adolf Huttl, "Nuclear Power in Eastern Europe and the CIS - An International
Challenge," Special Session #6, World Energy Conference, Madrid,
Spain, September 1992, p. 3.
Birkhofer (1992), p. 3.
Huttyl (1992), p. 3.
Ibid., p. 4.
IAEA (1993), p. 10-11.
E.O. Adamov et al., "Making the Most of the Remaining RBMKs:
First-Stage Upgrade Completed at Leningrad-1," Nuclear Engineering
International, September 1992, p. 18.
Ibid., p. 19-20.
"Datafile: Ex-USSR," Nuclear Engineering International,
August 1992, p. 37.
Ibid., p. 38.
Andrei Gagarinski, "Great Expectations," Nuclear Engineering
International, November 1992, p. 51.
Judith Perera, "Why Russia Still Wants Nuclear Power," New
Scientist, 8 May 1993, p. 29-30.
B. Maddox, "Damage Limitation in a Death Zone," U.K. Financial
Times, 17 November 1993, p. 6.
"Economic Meltdown Leads Ukraine to Resume Building Nuclear Plants,"
The Ottawa Citizen, 22 October 1993, p. A-7.
"Those Reactors at Chernobyl," The Washington Post, 30 October
1993, p. A20.
Janet Wood, "Ukraine Takes on the Burden," Nuclear Engineering
International, August 1993.
"News Briefing," The Uranium Institute, 17-23 November
1993, p. 1.
Wood (1993), p. 40.
"Eastern Europe's Nuclear Power," The Economist, 24 July
1993, p. 20.
Wood (1993), p. 40.
Howard Witt, "Officials Dare to Re-open Unsafe Reactor," Ottawa
Citizen, 24 November 1993, p. A5.
Yanko Yanev and Ian Facer, "Backfitting Kozloduy for Continued Operation
at Less Risk," Nuclear Engineering International, December
1992, p. 16.
"EBRD Rescues Kozloduy Nuclear Reactors," The Petroleum Economist,
Vol. 60, No. 8, August 1993.
Yanev and Facer (1992), p. 17.
"East European Energy Report," Financial Times, Issue
17, February 1993, p. 11.
Nucleonics Week, 11 November 1993, p. 1.
"What's to be Done about Old VVER-440s?" Nuclear Engineering
International, May 1992, p. 49.
"West Rescues East's Nukes," Petroleum Economist, June
1992, p. 14.
"East European Energy Report," February 1993, p. 7.
"Eastern Europe's Nuclear Power," The Economist, 24 July
1993, p. 20.
"Datafile: Hungary," Nuclear Engineering International,
March 1992, p. 52.
"Still Making Headway - Just," World Survey, Nuclear Engineering
International, June 1992, p. 15.
Sergio Finzi, "Contribution of the Commission of the European Communities,"
Special Session, Nuclear Power in Eastern Europe and the CIS - An International
Challenge?, World Energy Conference, Madrid, Spain, September 1992, p. 1.
Ibid., p. 3.
1 ECU (European Currency Unit) = Cdn. $1.50 (approx.).
Finzi (1992), p. 3.
Ibid., p. 4.
"East European Energy Report" (1993), p. 1.
"Into the Labyrinth: A Guide to Aid for Operators of Soviet-Supplied
Reactors," Nuclear Engineering International, May 1993, p. 40.
Ibid., p. 41.