There is now very little hope for the 64 workers missing after the explosion at Rushydro’s giant Sayano-Shushenskaya hydroelectric plant in East Siberia. At the time of writing, rescue workers were still searching for survivors in the flooded 287m long powerhouse, and 1000 employees had been brought in to reinforce the 100 strong rescue crew at the plant where at least 11 people were killed and 14 were injured on 17 August when a huge pulse of water burst into the facility’s main machine room. Because of the freezing temperatures survivors could only be expected now if they were lucky enough to have been inside an ‘air bubble’ protecting them from the freezing, 4°C, water.
The plant in the Khakassia republic, four time zones east of Moscow, is the country’s biggest, with a 245 m high concrete dam holding a reservoir stretching over 621 sq km. There is still some disagreement about the cause of the tragedy. A manager and former director of the station, employed by the plant’s owner Rushydro, has suggested that a technical fault in a turbine was to blame for the disaster. ‘A turbine was destroyed, and indicators show that this was not caused by the water surge but by a broken turbine lid’ Alexander Toloshinov told a meeting with relatives of the missing workers in the village of Cheryomushki, where the plant is located. Energy minister Sergei Shmatko had already ruled out a transformer explosion or repair works, two explanations put forward previously.
But Emergency Situations minister Sergei Shoigu has said the reason for the accident had not yet been established. ‘The basic reason was a water surge, and the reason for that is not clear yet’ he told reporters. Shoigu also said there was no danger of a dam leak or break. ‘We can say for sure that there is no danger for the local population. There will be no flooding’ he said.
It has been reported that engineers had warned in 1998 that the dam’s foundation was weak because of misconstruction faults and that there was a real danger that the giant concrete construction might collapse.
The disaster is likely to have serious consequences for Russian industry. Electricity prices in the region have already jumped five fold on the spot market causing prime minister Putin to order a thorough look at the implications. Russia’s Energy minister said electricity prices in Siberia could anyway rise by about 7% because more expensive coal fired power stations will have to increase production. RusHydro itself lost 7% of its
capitalisation in the hour after the accident. Its shares, which were recently floated on the London stock exchange, are now suspended Rusal, one of the world’s major aluminium producers, could be among the companies hit hardest by the price rise because its high consumption means the price of electricity is crucial for its profitability. It may have to cut its output for that reason alone, but in any case Rusal said that output from its smelters may have to be reduced as part of the wider plan to ensure sufficient electricity for the region this autumn and winter.
Energy analysts are predicting that repairs are likely to cost between a half and one and a half billion dollars. But the company is known to have substantial cash reserves. It did very well during 2008, and its debt position is very strong so the general belief is that the company should have no difficulty in borrowing the money to fix the Sayano-Shushenskaya plant.
It is also suggested that the accident will change Russia’s energy balance, boosting coal at the expense of water. Rusal and Rushydro, who have for months disagreed over the financing of Siberia’s new hydro-power plant Boguchaskaya, may have to patch up their differences and launch it as soon as possible.
Immediately after the explosion several of the plant’s ten generating units were found to have been damaged. The concrete arch gravity dam was not affected by the accident, RusHydro reported.
Operations were suspended, water in the system was drained down and inflows to the reservoir spilled by the partial opening of all 11 of the dam’s gates.
Investigations into the cause of the accident continue. RusHydro said that early views suggest that possibly there was some hydraulic equipment rupture or failure, and partial destruction of the powerhouse. Heavy damage was suffered by the hydraulics of units No 7 and No 9. Parts of the building structure fell on units No 3, 4 and 5.
RusHydro said a week before the disaster that the 6.4 GW facility, completed in 1985 on the Yenisei river, had been benefiting from higher inflows and was expected to continue to do so over the next couple of months. The plant was being operated at a higher load and this, too, was planned to continue.
More than 15 000 GWh had been generated by the plant in the year so far. One of the 10 generating units (No 6) has been undergoing refurbishment since January and the work was due for completion this month. It was commissioned in 1981, three years after the first units were brought into service.
The Sayano-Shushenskaya subsidiary company within RusHydro has a total of 6721MW of installed capacity in two plants. Sayano-Shushenskaya is the flagship of RusHydro’s expanding fleet, which consisted of a total of 25 336 MW of installed capacity at the end of 2008.
