Nuclear power provided Bulgaria a way of easing its dependence on imported fuels, although the Soviet Union and Czechoslovakia provided the expertise and equipment on which Bulgaria built its nuclear power industry. Lacking hard currency to buy enough oil, and reaching the toleration limit for pollution by coal-burning plants, Bulgaria increasingly made nuclear power the center of its energy policy in the 1980s. In 1974 the first nuclear power plant was opened at Kozloduy north of Sofia on the Danube River. After completing the original four-reactor complex in 1982, Kozloduy added a fifth unit in late 1987. This was the first 1,000-megawatt reactor in Eastern Europe outside the Soviet Union. A sixth unit was installed in 1989. At that point, Bulgaria ranked third in the world in per capita nuclear power generation, and the extent of its reliance on a sole nuclear power plant was unsurpassed in the world.
The Bulgarian nuclear power industry was beset with major problems from the beginning. The Kozloduy station had a history of technical difficulties and accidents, many of which were related to the low quality or poor design of Soviet and Czechoslovak equipment. The fifth reactor, a constant source of trouble, was out of commission for several months in 1991 because of extensive turbine damage. This setback put the entire country on a brownout schedule that shut off electricity two out of every four hours.
The Chernobyl' disaster in 1986 made nuclear safety a sensitive political issue in Bulgaria, and by the late 1980s public opinion, now a much more significant factor for policy makers, had turned strongly against the nuclear industry. A second nuclear power complex was started at Belene, to add six 1,000-megawatt reactors by the end of the Tenth Five-Year Plan. But construction was halted in 1989 by public opposition and disclosure that both Kozloduy and Belene were located in earthquake-prone regions. Long-term plans for nuclear heat generation also were shelved at that time. In 1991 the government's Commission on Nuclear Power Supply reported that the supply system was poorly organized and managed, and that managers relied on expensive foreign technical help instead of available domestic engineers. The commission also reported that, once Soviet specialists left, a shortage of qualified personnel delayed activation of the sixth reactor at Kozloduy (considered a top priority once Belene was rejected), and that most monitoring instruments in the first four Kozloduy reactors were out of operation.
In mid-1991 the International Atomic Energy Agency (IAEA) declared the Kozloduy reactors unsafe. Two reactors were shut down. Meanwhile, the planned activation of the two newest reactors at Kozloduy raised the problem of nuclear waste disposal in 1991, because the Soviet Union began charging hard currency to reprocess waste from East European reactors, formerly one of its functions under Comecon. In 1991 Bulgaria requested European Economic Community (EEC--see Glossary) aid to build its first permanent domestic repository for nuclear waste.
The Bulgarian power transmission network was supplemented in 1988 when a high-capacity transmission line from the South Ukraine Nuclear Power Station in the Soviet Union reached the northeastern port city of Varna. But like Soviet fuels, imported Soviet electricity required hard currency in 1991, mitigating the advantages of the old CEMA agreement.
Data as of June 1992