The Novovoronezh Atomic Energy Station (NVAES). All photos by Sergey Kuksin
For the last month the Novovoronezh AES has been operating under heightened control. That this site is indeed strategic was clear even before we entered the plant. It took our group more than an hour to pass through various layers of security: from the thorough document check by silent guards to body scans in state-of-the-art equipment.
The day we visited, the atomic energy station was in the midst of another emergency-procedures training. It simulated the nightmare of all atomic scientists, the Fukushima scenario: the loss of all electricity to the plant, including systems meant to cool the reactor. In other words, a complete loss of control over the situation in the power plant’s “nuclear boiler”.
“All Russian stations owned by Rosenergoatom are now undergoing trainings like these,” said Vladimir Povarov, director of the Novovoronezh AES. “None of this has been specially organised for the readers of Rossiyskaya Gazeta.”
The day before, Povarov added, similar trainings took place at the Balakov and Kalinin atomic energy stations. The next level of training will simulate a scenario involving the “complete loss of cooling water”. At the Novovoronezh station, the assignment was made even harder by combining two hypothetical nightmare situations with a “fire at the transformer substations”.
The Novovoronezh AES, located around 600 km to the south of Moscow, is the same age as the Fukushima plant. Their first power-generating units were built in the 1960s and 70s. At the time, it was cutting-edge science and state-of-the-art technology. According to Sergei Novikov, press secretary for Rosatom, the state corporation that controls Russia’s nuclear complex, all types of water-to-water energy reactors (VVER) were perfected at the Novovoronezh AES. They were then mass-produced and are now in operation not only in Russia, but in other countries as well. Meanwhile, the new ones are being built, including in India. Of the five power-generating units originally built at Novovoronezh, only two are now operating. The first two units have served their time and are being taken out of operation. The fifth and most powerful unit was stopped last September for scheduled repairs and serious modernisation. At a little distance, two new reactor units are being built for the Novovoronezh AES-2.
One often hears atomic scientists from different countries say: Fukushima is just an old plant. Its reactors are more than 30 years old; the first one is over 40. Why is Novovoronezh any better? Could a Fukushima-like scenario happen here? This was the first and most important question posed by readers of Rossiyskaya Gazeta.
“The Japanese were let down by their security system. First the earthquake put the main power supply out of commission, then the emergency generators for cooling the reactor were deluged by the tsunami, and that’s when the overheating began. At our atomic energy stations the security system is of a different construction,” said Povarov. “The Japanese scenario could not happen here. Our reactor is of a fundamentally different construction: unlike Fukushima’s, our installations are double-contoured. Plus our large reserves of water allow us to remove the remaining heat released in an active zone. For around six hours we may, without interfering, without managing the accident, activate additional power-supply systems. In critical situations, this may be of decisive importance.”
In the world today there are two main types of reactors: the BWR (boiling water reactor) and PWR (pressure water reactor). The Russian equivalent of the PWR is the water-to-water energy reactor (VVER). In pressure reactors like the VVER-1000, the water temperature reaches 330 degrees, but the water never boils because it’s under great pressure. The water in the first contour (it flows round the reactor’s active zone) does not come into contact with the water in the second contour, where the steam is generated that turns the turbines. This is why it is a safer technology. The Fukushima reactors are called “boiling” reactors because the water in them boils, heating up under pressure to about 280 degrees. Steam is produced in the reactor and immediately released into the turbine. Because of this, additional precautionary measures must be taken.
The trainings were successfully completed. The “accident” was handled in 1 hour and 10 minutes. We were shown how even when the station’s whole power supply is cut, the troubled unit is quickly reached by a powerful mobile diesel generator capable of pumping huge masses of water to cool the reactor. Meanwhile, firefighters doused the flames in the supposedly burning transformer substations within minutes. In other words, our atomic scientists displayed their reserve systems and back-up safety systems in all their glory. These are systems to which Fukushima did not have access at the critical moment and which, we were told, are ready to go at Novovoronezh. But would things run so smoothly in a real crisis situation?
“We have simulated all sorts of accidents at AES right down to the breakage of an ordinary screw. Even if someone wanted to bungle something, they wouldn’t be able to: every one of our decisions, every button pushed is watched by people and video cameras. Here we are constantly upgrading our qualifications and crisis management skills,” said Dmitry, who works with the AES.
Some 3,700 people work at the Novovoronezh AES. At the work stations there is complete quiet, while the power-generating units are immaculately clean and manned by people in white protective suits and masks. “I’ve worked here for over three years. This day is no different from any other. We’re constantly keeping order!” said 27-year-old Sergei Prokhorov, who works in the turbine section of the fourth power-generating unit. He earns a very good salary for his region of Russia: around 40,000 rubles ($1,400) a month. The average salary at the AES is between 40,000 and 50,000 rubles a month. Specialists earn substantially more. The system of social benefits at the AES is also good. Employees may take out loans and mortgages at the enterprise, said Sergei.
“The people who work here don’t want to lose their jobs, and that’s an important guarantee of conscientious work and safety at the AES,” Povarov stressed.
The operators at the power-generating units have advanced degrees in engineering and make their decisions knowingly, the director added. “In other countries the personnel, as a rule, do not have special education and work according to instructions. But even the most perfect set of regulations cannot foresee all emergency situations. Maybe that’s why in Japan the response was delayed.”
According to those who visited the AES, their acquaintance with the atomic energy station — the reactor, the machine room and the work of the emergency brigade in a crisis situation — made a positive impression.
“I was pleasantly surprised by the certainty among employees at the station that nothing like Fukushima could ever happen here. The moral aspect, it seem to me, is also important,” said Alexander Pylev, 55.
More difficult questions followed. What would have happened if at Fukushima, instead of the three operating reactors and the three reactors under repair, there had been five power-generating units like the ones here at NVAES?
“Fukushima for us is out of the realm of science fiction. In our region, earthquakes measuring over 4 on the Richter scale cannot happen, though the station is designed to sustain one measuring up to 5,” said Povarov. “Of course, there would have been some destruction. But given that the reactor systems are designed to withstand a magnitude of up to 9, they would have continued to function. And we’re in no danger from tsunamis,” the director concluded.
Sergei Novikov, the Rosatom representative, reminded us that if in Russia there are no atomic energy stations located in zones where an earthquake with a magnitude of 9 is possible, there is a Russian-designed AES now being built near the city of Kudankulam, in southern India, that is made to sustain a strong tsunami. “Several years ago when a giant wave covered Thailand and rolled all the way to India, the station withstood it. Local residents, knowing that the AES was equipped with means of defense against tsunamis, came running to the construction site, and hid there and survived,” said Novikov.
Readers of Rossiyskaya Gazeta were also shown the new atomic energy station, Novovoronezh AES-2, which is being built according to the same design as the station in Kudankulam in India’s southern state of Tamil Nadu. It is equipped with ultra-modern and even more powerful defence systems. One of them is a meltdown trap. If such a “trap” had existed at Fukushima, meltdown products would not have wound up in the atmosphere. “This construction can localise a meltdown of nuclear fuel that could melt through the bottom of a reactor and leak out,” explained Ruben Topchiyan, deputy director of Atomenergoproekt. “It localises it and contains it.”
These traps are truly an innovation at Russian atomic energy stations. They are something like large steel pressure cookers with double walls weighing more that 800 tonnes; they are placed under the reactor. The trap itself and the space between the walls are filled with cartridges of sacrificial material (granules of oxides of aluminum and metal). In the highly unlikely event of a meltdown of fuel-material elements, said Topchiyan, they will flow into this trap and react with the sacrificial material which, by binding the radioactive matter chemically and physically, will not allow it to leak out of the trap.
The new station will also have passive safety systems that work even when all power has been cut. There is a reserve of water for cooling over 72 hours and draining heat from the reactor zone. As the energy specialists themselves say, such safety requirements which are there in Russia do not exist anywhere else in the world.
Residents of Novovoronezh (population: 30,000) are very proud of their atomic energy station. “It is our town’s calling card. If not for this station, the town would not exist. Almost every family here is connected with the AES,” said Elena Stepanova, a local resident.
True, some residents of 850-year-old Voronezh, located just 40 km from the AES, especially of the older generation, are not so happy about it, but the outlook among locals is largely positive.
“The radiation background at the station is within the norm; moreover, it’s even lower than in certain cities in our region,” says Alexander Mamatov, head of the radiation safety service. “Control over the radiation state of the station’s environs was established a long time ago. There are countless monitors both at the station and within a 30 km. zone around it. Roughly 20 checkpoints around the whole radius are connected by a single network and relay in real time all information at the AES and at the crisis center at Rosenergoatom.”
VVER reactors will remain for a long time to come the basic ones for the production of electricity the world over, including in Japan, stresses Povarov.
“These are powerful, economical reactors, especially those of the last generation, equipped with additional safety systems. The cost of energy is substantially lower than energy from electric power stations, around 800 rubles a megawatt, or 8 kopecks a kilowatt. In future reactors running on rapid neutrons will go into operation.”
“Russia is the only country now equipping such a reactor (the VN 800 at the Beloyarsk AES), next to an operating VVER reactor. We, in Russia, are the purveyors of this unique technology. The idea is to realise a closed fuel cycle: to use in a reactor running on rapid neutrons the fuel already used in a thermal reactor (uranium 238).”
All rights reserved by Rossiyskaya Gazeta.