Environmental Engineering Reference
In-Depth Information
MW (and are thus referred to as 1000 units, etc.). There are two basic types
of VVER-440 reactors, which are based on different safety philosophies.
The VVER-440/230 design comprise the Generation I reactors, while the
VVER-440/213 represents the Generation II reactor design with reduced
pressure containment. There are two specifi c VVER-440 designs currently
in operation: the Finnish Loviisa NPP with reduced pressure western-type
containment and the Armenian Medzamor NPP. In the VVER 1000 MW
series, there was a gradual design development through the fi ve oldest plants
(small series), while the rest of the operating plants represent the standard-
ized VVER-1000/320 model. More VVER-1000 units were commissioned
recently and those currently under construction are improved versions of
the VVER-1000/320. For example, the Tianwan (China) plant with AES-91
type units and the Kudankulam (India) plant with AES-92 type units. New
VVER models, such as the AES-2006 design, are being considered for
future bids; these new evolutionary models of large VVERs already exhibit
Generation III features.
The design operational lifetime of the VVER plants is generally 30 years,
with the exception of the new VVER-1000 type units which have 50 or 60
years of designed operational lifetime. A great majority of VVER plants
are quite old, nearing the end of their design lifetime, except for some in
Russia. The VVER operating countries are dependent on nuclear power
production, for example the Paks Nuclear Power Plant in Hungary pro-
vided 40% of domestic production in 2010. The nuclear power capacities
in these countries ensure the necessary diversity of power generation and
contribute to the security of supply. Therefore, the VVER owners in Central
and Eastern Europe are keeping their plants in operation via implement-
ing plant lifetime management (PLiM) programmes, with the intention of
ensuring a safe and fi nancially viable operation in the long term. The PLiM
practice of VVER plants is presented by Katona (2010) and Katona and
R á tkai (2008, 2010).
The possibility of extending the operational lifetime of VVER-440/213
plants was recognized in 1992. It was based on an assessment of the robust-
ness of the design, good technical condition of the plants and synergy
between safety upgrading measures and overall condition of the plants
(Katona and Bajsz, 1992). In all VVER operating countries, lifetime man-
agement had the explicit goal of ensuring the extension of operational life-
time (Rosenergoatom, 2003).
The operational licence of the four VVER-440/213 units at Paks NPP in
Hungary, is nominally limited to the design lifetime of 30 years. Extension
of the lifetime of this particular plant by an additional 20 years is feasible.
The fi rst formal step of licence renewal of the Paks NPP was made in 2008
and the relicensing process is still ongoing. In Ukraine, the nuclear share of
domestic production of electricity is approximately 48%, while this nuclear
Search WWH ::
Custom Search