The disaster at the Chernobyl nuclear power plant exposed fundamental flaws in the RBMK-1000 reactor. Despite this, reactors of this type are still operating in our country.
Cool technologies are big risks. According to the World Nuclear Association, for 1 gigawatt year of electricity produced at nuclear power plants, there are far fewer human casualties than for energy from other types of power plants. But accidents at a nuclear power plant are truly catastrophic in their consequences.
Today, 10 RBMK-1000 reactors are still operating in Russia. Exactly the same reactor exploded in April 1986 in Pripyat. Yes, as a result of that disaster, the RBMK design was modified, but can we be sure that these reactors are now safe?
RBMK-100 were designed specifically to run on less enriched fuel. Reactors of this type use water as a coolant, and graphite as a moderator. Because of this separation of the roles of the coolant and moderator, the principle of negative feedback “more steam - less reactivity” did not work in RBMK.
In the reactor of the Chernobyl nuclear power plant, the increase in power in the reactor caused processes that led to a further increase in power, which was one of the main causes of the disaster. After a terrible accident, changes were made to the design of operating RBMK-1000s: more enriched fuel was used, the number of control rods was increased, additional inhibitors were introduced to avoid losing control over the reactor at low powers.
Despite the measures taken, nuclear safety experts have expressed strong doubts about the RBMK-1000. "[These reactors] are not as good as the European ones, although they have become less dangerous," says Lars-Erik de Geer, a nuclear physicist in Sweden. “There are fundamental properties of the [RBMK-1000] design that cannot be corrected in any way,” adds Eric Lyman, Project Leader for Nuclear Safety at the Union of Interested Scientists. "It is hardly possible to improve the safety of RBMKs as a whole to the level that can be expected from a similar Western-style reactor."
There have been no nuclear reactor incidents in the former USSR since the Chernobyl disaster, but the use of the RBMK-1000 still raises concerns. Perhaps, after some time they will be completely abandoned, but until then we will feel like a powder keg.
