Electricity + Control August 2015

ENERGY + ENVIROFICIENCY

Generation III+ VVER nuclear reactors

By D E Kolchinsky, A V Molchanov, V V Bezlepkin, A M Altshuller (St Petersburg Atomenergoproekt (a branch of VNIPIET)), Russia, and Ryan Collyer, Rosatom South Africa

The common name for the Water-Water Energetic Reactor (VVER) is Pressurised Water Reactor (PWR). It is the most widely used nuclear power reactor technology in the world today.

V VER (Water-Water Energetic Reactor) is one of the most suc- cessful and influential branches of nuclear power plant develop- ment, and the technology is widely distributed throughout the world. VVER technology was developed in house by OKB Gidropress, a research division of global nuclear company Rosatom, while the nuclear power plant projects using this technology were implemented by three engineering organisations of this company – Atomenergo- proekt in Moscow, St. Petersburg and Nizhny Novgorod. However, the Russian VVER reactor and the materials used for its construction differ significantly from other PWR reactors. The main features of the VVER are as follows: • Use of horizontal steam generators, which reduces the risk of corrosion and malfunction, facilitates repair and maintenance and ultimately reduces costs • Use of hexagonal fuel assemblies, which increase the technical and economic characteristics of the fuel by increasing the duration of the campaign and the introduction of extended fuel cycles • Preventing the release of fission products outside the sub-reactor cavity, based on completely independent systems and taking into account all requirements of the IAEA, including the ‘post- Fukushima’ standard SSR-2.1 • High-power pressure compensation system, ensuring a long, safe and failure free operation steam-generating unit Fifty years’ experience has been accumulated through the successful operation of NPPs using VVER technology and a total of over 1 400 reactor years have been achieved. Nuclear power plants with VVER- type reactors are built with the participation of Russian specialists

in Finland, Czech Republic, Slovakia and Hungary amongst other countries. NPPs designed according to VVER-1000 technology were built in Russia (units 1 - 4 of Balakovo NPP, units 1 - 4 of Kalinin NPP, unit 5 of Novovoronezh NPP and units 1 - 2 of Rostov NPP), in Bulgaria (units 5 - 6 of NPP Kozloduy), in Ukraine (units 1 - 3 of NPP South Ukraine, units 3 - 4 of NPP Rovno, units 1 - 6 of NPP Zaporozhe and units 1 - 2 of NPP Khmelnitski), in Czech Republic (units 1-2 of NPP Temelin), India (units 1 - 2 of NPP Kudankulam), Iran (unit 1 of NPP Bushehr), China (units 3 - 4 of NPP Tianwan). NPPs designed according to the project ‘NPP-2006’ are currently under construction in Russia, Belarus, and Turkey and are expected to be constructed in Finland and Hungary. The project has more capacity due to the increased capacity of the power units (not less than 1 150 MWwith the possibility of increasing up to 1 200 MW), which will reduce capital and operating costs, as well increase economic efficiency of the project. In addition to greater capacity, the project includes a combina- tion of active and passive safety features: active safety systems are able to function when at least one of the alternative power sources is available. Passive systems are able to function independently, without power, and without human intervention. The project also provides resistance to the design basis and beyond design basis accidents, calculated on a full-featured simulator — mathematical model of a virtual power unit. The main principles underpinning the AES-2006 design are: Maxi- mum use of proven technologies; minimum cost and construction

Electricity+Control August ‘15

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