Serbia: HPP Djerdap stable electricity production and overhaul cycle

, News Serbia Energy

In HPP “Djerdap” planned annual production is 6.59 billion kilowatt-hours, while energy produced until mid-April reached 2.82 billion kilowatt-hours, which is 37 percent more than planned for this period.

If we can anticipate further results judging by those behind us, this year will be another record year in HPP “Djerdap”, and we shall carry out all planned overhauls, Slobodan Stamenov, Director of production in HPP “Djerdap” says, providing an abundance of data that supports this claim.

In HPP “Djerdap” planned annual production is 6.59 billion kilowatt-hours, while energy produced until mid-April reached 2.82 billion kilowatt-hours, which is 37 percent more than planned for this period.

– Production this high was achieved thanks to the well done overhauls during the past year, favorable inflow of rivers and melting snow in the mountains – Stamenov says. – The annual planned production of energy in HPP “Djerdap 1” according to the dynamic plan is around 4.86 billion kilowatt-hours, while energy produced until April 15 reached two billion kWh. That’s 36 percent more than planned for the period January – mid-April.

HPP “Djerdap 2” has so far exceeded production plan by 26 percent and has produced 537.27 million kWh to mid-April, while the planned annual production is 1.43 billion kilowatt-hours.

HPP “Pirot”, according to Stamenov, has fulfilled this year’s production plan. Projected energy for this year according to the dynamic plan was 66 million kWh. The plan has been fulfilled since April 8 and so far 67.63 million kWh have been produced.

“Vlasina hydro power plants” are also striving towards new records because the plan was exceeded by 81 percent.

– It even happened that deterrence of rivers Ljubata and Dragovišnice was done several times during March and April this year due to high water levels in the Lisinsko lake – notes Stamenov.

In “Djerdap” the overhaul plan for this year has been done, which should increase the operational readiness of all hydropower plants and in the “Djerdap” system. In the HPP “Djerdap 1”, revitalized hydro power unit A5, after final testing and continuous operation for 72 hours, has been synchronized with the power system. After 9,706 hours of operation on the revitalized power unit A4, the control and maintenance operations began mid-April and will last to the 8th of May. According to the contractual obligations with the contractor OAO “Silovije masini” from St. Petersburg, operations were to be carried out after 8,000 hours’ work of the machine, but due to the high influx of the Danube and the necessity of operation, the review has been delayed.

During operational standstill it is necessary to review and work on the moving blades of the impeller (depth control and control of surface damage from runner blades cavitation, the amount taken materials determination, peripheral edge of the moving blades repair, recovery of leakage in the sealing portion of the blade no. 4, inspection of clearance in the turning impeller), the hub of the impeller, trim impeller turbines, welds in inspection opening, works on the carrier and the guide bearing, the turbine control system, the hydraulic part of the regulator and servomotors. There is also an overview of the stator and rotor of the main and auxiliary power units.

Start of the reconstruction-recovery of power unit A1 is planned from June 1, with the replacement of the new and revitalized equipment from programs with Russia, with an increase in power and performance of power units. Hydro generators A2, A3 and A6 will this year be submitted to regular annual review (care) for a term of 12 days. After Sync, unit A5 will be inspected after 2,000 to 4,000 hours. Activities will last a maximum of 15 days.

Overhaul of canal locks

Starting from June this year a major overhaul is scheduled on the canal lock, which will last five months, when all the perceived shortcomings will be inspected and repaired, says our source.

According to Stamenova in HPP “Djerdap 2” on the A2 a month and a half overhaul is planned, while the A3 to be overhauled for nearly four months. A major overhaul of the A4 for a period of 105 days is also planned. On the other power units, 10 day-maintenances are planned in July, August and September. The ship lock in HPP “Djerdap 2” also goes into capital overhaul for a period of three months.