How Rostov-2 started up

The construction of twin 1000MW capacity units of the Rostov (Volgodonsk) nuclear power plant in parallel started in 1979, but the project was mothballed in 1990. In 1998 it was resumed, and the first nuclear power unit was put on line in 2001. The next year, the examination and survey of Unit 2 started. In 2006, a supplement to the Rostov NPP project covering Unit 2 was issued. In 2007, the document passed a review by the Federal Agency for Construction, Housing and Public Utilities (Rosstroy).

The same year, the Unit 2 construction completion was started. The Directorate for Construction of Rostov NPP, a branch of Rosenergoatom, was designated the building owner. The principal contractor for the project was designated to be the Nizhniy Novgorod Engineering Company Atomenergoproject (NN AEP, formerly the Gorky Atomenergoproject, the architect of Rostov NPP).

At the start of the intensive construction phase, the schedule delay was enormous.

In September 2006, the reactor building construction had slipped by 28 months. A year later, the turbine island delay was 24 months.

Regular financing of the work became the key objective. In 2008, about RUB12bn (EUR3.29 million) were allocated for the unit construction, and about RUB30bn in 2009.

In addition, NN AEP nearly doubled its personnel by bringing in new workers from non-nuclear construction sites who were trained by nuclear construction specialists. In peak periods the construction site employed about 10,000 workers.

The project gradually caught up with the schedule. In December 2008, the reactor building erection was just eight months delayed. The turbine island construction caught up with the schedule in autumn 2009. In the end, it took only two years to build the facility, a process that should have taken twice as long. By then, preparations for commissioning had begun. Below is a diary of major events in commissioning the reactor during a key six-month period.

The Rostov 2 reactor vessel is lowered into place

10 October 2009: Extended thermal and hydraulic tests begin, including test runs of all reactor systems, equipment and protection features. The primary and secondary circuits are subjected to pressure tests to verify their integrity and strength. Main circulation pumps (MCPs) are tested at cold and hot reactor conditions. Also, the in-house power supply systems are tested in conditions of power supply interruption and loss of all power. A comprehensive check of the reactor control and protection system is carried out.

30 October: A hot and cold run of the reactor is successfully completed. This work involves about 500 specialists from more than 20 organizations.

1 November: A 10-day-long integrity and strength test begins. The technical condition of sealed enclosure structures and systems are tested at an internal pressure exceeding 4.6 kg/cm2. The test revealed hidden installation deficiencies that could be fixed.

3 November: The Rostov-2 commissioning control panel learns at its 10th meeting that during the first criticality programme, 480 rooms had been accepted for temporary and permanent operation; 63,492 butt welds were made at process systems; 1,615 valves, 234 motors and 193 pumps were trialled; 131 ventilation systems were commissioned; and 1,222 local commissioning operations were completed.

7 November: The containment tests finish successfully. In parallel, the commissioning-related work continues on the refueling machine and systems for handling and storage of nuclear fuel. The irradiated nuclear fuel hold-up pond passes the final integrity test.

19 December: The Rostov-2 startup and commissioning programme begins. The first fuel assembly is loaded into the reactor core to mark the start of the first criticality program. Russia’s vice prime minister Sergey Sobyanin attends.

24 December: Reactor loading finishes. A total of 163 fuel assemblies were put into the core

Hexagonal fuel assemblies make up the first core load of Rostov 2

22 January 2010: The reactor is brought to the minimum controlled power.

20 February: The first power and power build-up programme begins. In the first stage, power will approach 10-12% nominal and pilot operation at 35% nominal. In the second stage, which continued at time of writing in mid-April, the reactor was rising to normal operation at 35% power and synchronizing the generator with the grid, as well as pilot operation at 40% and 50% power levels. Other tasks in this programme include a test idle run of the turbine generator; routine tests of reactor process systems and safety systems; and trial operations to synchronize and connect the generator to the grid.

24 February: The ‘turbine kick’ is performed, a no-load speed build-up of the turbine generator rotors. Readings obtained during the turbine generator tests at the design rotation speed of 1,500 RPM were evaluated as good by service engineers.

6 March: Generator synchronisation and grid connection adjustment work begins. The work includes a check of conformance between equipment and systems’ actual parameters with their design values, to ensure safe and reliable operation.

17 March: Nikolay Kutiyn, chairman of the federal environmental, industrial and nuclear supervision service (Rostechnadzor) arrives at the site for a working visit. He concludes that the construction license conditions are met; there are no regulatory breaches, and nothing prevents grid connection.

18 March: The unit is commissioned. Russia’s prime minister Vladimir Putin attends. At 4:17pm (Moscow time) he permits shift supervisor Vadim Sotnikov to start building up power up to 300 MW. The unit is connected to the grid and starts releasing electricity to Volgograd, Rostov, Krasnodar and Stavropol regional power systems in the North Caucasus region (which has a total population of 17.7 million). The station’s next target, set for May, is to build up reactor power to 50% of nominal.

30 March: The unit’s is rated highly by experts of the Moscow centre of the World Association of Nuclear Operators (WANO) who had carried out a pre-startup peer review on the site. For two weeks prior, nuclear experts from Armenia, Belgium, Bulgaria and other countries inspected Unit 2. They reviewed personnel performance in organisation and administration, operation, maintenance, engineering support, radiological protection, training and qualification.

At time of writing, the commissioning activities continue proceed on schedule. Shortly, the federal regulatory authorities are to confirm availability of Rostov 2. A Rostechnadzor inspection is set for May 15. Then, a scheduled outage will start, and the power plant will be released for pilot commercial operation afterwards. Following pilot commercial operation, a series of delivery trials will begin. Based on those results, the unit will be accepted for full commercial operation. The procedure is slated for October 2010. Rostov 2 is expected to generate 3.7 billion kWh of power in 2010.

Rostov 3 and 4 are planned to be commissioned on the Rostov site in 2014 and 2017, respectively. The successful commissioning of Unit 2 gives hope that these will be accomplished strictly on schedule.