Moscow: Russia`s largest nuclear power plant with a rated generation capacity of 1,200 MW is expected to attain criticality in September, said a top plant official.
"The first criticality of the first unit will be in September. The unit will be connected to the grid in December," Vladimir Poronov, plant director and deputy chief manager Rosenergoatom, told a team of visiting international journalists.
According to Russian nuclear power sector officials, once the first unit goes on stream, it will be the largest unit functioning in the country.
"The average investment per kwh of this unit will be around $3,000. But this will not be the reference cost point for foreign clients. The cost for foreign clients will be much less, around $2,500 per kwh," Poronov said.
The second identical unit is expected to go on stream in 2017.
The two new units would be the 6th and 7th units in the Novovoronezh nuclear power plant complex.
Officials at the power plant told IANS that around 1,200 people will be working in the two units.
Construction activities at the plant site began in 2007.
Officials told IANS that pre-runup tests are being done at the first unit with dummy fuel assemblies, which are identical to real fuel assemblies but without uranium.
VVER-1200 units will use 163 fuel assembly bundles similar to the VVER-1000 model. However, the fuel weight and the length of the fuel assembly would be longer than what is being used in VVER-1000 model, officials told IANS.
Poronov attributed the delay in commissioning the project to the time taken to meet the stringent safety standards stipulated by the Russian atomic power regulator.
Another reason for the delay was that the Rosatom group company had to meet global supply orders and hence supplies to this unit got a bit late.
The Novovoronezh nuclear power plant, around 600 km from Moscow, is the first commercial nuclear power plant in the world with water-cooled and water-moderated (VVER) reactors.
A total of five VVER nuclear power plants were built and commissioned at this complex. Each of the reactors operating today is a prototype of standard VVER-440 and VVER-1000 power reactors.
While the first two units set up in 1964 and 1969 respectively have been shut down, the third and fourth unit commissioned in 1970 and 1971 respectively would be shut down soon.
The fifth unit is the prototype VVER-1000 unit with 1,000 MW capacity and is now running after undergoing a modernisation involving an outlay of 14 billion rubles.
Detailing about the features of the VVER-1200 units, officials said it is based on design AES-2006 generation 3+ using the latest achievements and developments while meeting all safety requirements post the nuclear accident at Fukushima in Japan.
The reactor`s life is 60 years.
According to AES-2006 design, one cooling tower is built per unit, instead of two built earlier.
The reduction in number of cooling towers reduces the overall project cost, space and power. The life of the cooling towers is put at 100 years.
Interestingly, the two cooling towers stand around 171 metres tall, the highest among all nuclear power plant cooling towers in Russia.
On the safety aspects, officials said the reactors have active and passive features.
The reactor is housed in double-wall containment with ventilated inter-wall space, preventing leak from the inside to outside.
Passive safety systems can operate even in case of loss of all power sources and are capable to perform all critical safety functions without active systems.
The design also provides for installation of a core melt localisation device or core catcher at the bottom of the containment. It is supposed to contain the core melt and cool it.
Queried about the backup, power officials said there are three diesel power generating sets of 6.3 MW capacity each.
