On reunification the Germans understandably wasted no time in closing down Soviet-design VVER-440s in operation at Greifswald and abandoning the VVER-1000 units under construction at Stendal (both sites in the former GDR, which was also home to the 70 MWe Rheinsburg VVER prototype, closed down on safety grounds prior to renification). With the Chernobyl tragedy still very fresh in the collective memory, the VVER, the Russian version of the pressurised water reactor (characterised by horizontal steam generators) was understandably deemed completely unacceptable by the Germans and their nuclear

regulators agreed (although it was and is of course a very different proposition from the graphite moderated RBMK technology employed at Chernobyl).

It is therefore something of an irony that Siemens’ preferred joint venture nuclear partner, now it has signalled its intention to leave Areva NP, turns out to be none other than Rosatom, Russia’s state owned nuclear monolith (see p35). And the prime focus of its interest, the aforementioned VVER.

But it is not entirely surprising. Siemens has a long history of involvement with Russia in general (including with Power Machines on gas turbines and on both fossil and nuclear steam turbines) and with the VVER in particular, notably in the area of I&C. A number of VVERs around the world (including projects in China, Bulgaria, Finland, Slovakia, Hungary and elsewhere) are for example equipped with TXS, the Siemens-developed safety I&C system. (Although, interestingly, this technology currently belongs to Areva NP and would remain with it following Siemens’ departure, but presumably could be the subject of negotiation.)

The Russians can point to a healthy (by recent nuclear industry standards) number of VVER projects in the planning pipeline (mainly in their domestic market but also elsewhere) and about a dozen units under construction around the world (including Bushehr in Iran, which interestingly started life as a Siemens (KWU) PWR construction project about 35 years ago and was subsequently converted, remarkably, to VVER).

The VVER technology itself also has attractive features, as the Finns, who have been operating two VVER-440s at Loviisa successfully for many years (albeit with Western I&C), will tell you, and which is evidenced by the consistently high load factors achieved by Loviisa over many years (as regularly reported in our associate magazine Nuclear Engineering International).

Siemens are not the only German fans of the VVER by the way. RWE has recently announced it is making a substantial investment in the twin VVER-1000 Belene plant under construction in Bulgaria (commended by the EC as an example of Generation III technology), with the chairman of the giant utility describing the technology as being “in the champions league with regard to safety, efficiency and economic viability.”

It is certainly true that the VVER has come a very long way in the last couple of decades or so, with significant inputs from the Finns on the safety side. The latest manifestation, the VVER-1200, is in the same league as Areva’s EPR, while the version currently being built at Novovorenezh (see p 37), with its passive safety features, can justifiably claim to be the world’s first Generation III+ reactor to enter the construction phase (the second being the AP1000 project at Sanmen in China, where start of construction is imminent).

There is also another key consideration, which must be weighing heavily in Siemens’s considerations: the VVER-1200 looks relatively cheap, at least if the reported costs for Novovoronezh Phase II and Leningrad Phase II are anything to go by, about $2.5-3 billion per 1200 MWe unit, presumably with the potential for further cost reductions from serial production. If the Russian technology can also achieve fast construction times (a goal that so far proved elusive at Areva NP’s OL3 EPR project) then this Russian–German nuclear fusion looks like a very good option for Siemens.

James Varley is the managing editor of Modern Power Systems