Low Danube levels prompt review of cooling-water protection
Bulgaria is considering new infrastructure around NPP Kozloduy after unusually low Danube levels led to the country’s first precautionary nuclear output reduction tied to current hydrological conditions. The government is examining construction of a new levee near the plant to reduce vulnerability to prolonged drought and extended periods of low river flow. Energy Minister Iva Petrova said the proposed works would provide a more durable response to a problem that has become increasingly relevant for Bulgaria’s largest baseload electricity source.
On 21 August, output from one of Kozloduy’s two 1,000 MW units was reduced by about 120 MW as a safety measure. Danube levels recovered somewhat after the curtailment, lowering the immediate risk of further reductions. The episode highlighted how thermal and nuclear generation are exposed to more variable water conditions.
Nuclear reduction does not affect wider electricity balance
The precautionary reduction did not create a wider Bulgarian supply problem. Electricity production has recently been running at about 131,000 MWh per day, compared with domestic consumption of roughly 90,000 MWh. Exports have been close to 30,000 MWh per day, leaving Bulgaria with a sizeable system surplus even during the nuclear output cut.
Thermal unit returns support availability while repairs continue
Thermal availability is also improving following maintenance activity. Maritsa East 2 unit 7 has returned after repairs were completed ahead of schedule. Unit 8 is expected back before the end of August.
Bulgaria’s longer-term focus on permanent water-protection infrastructure indicates that low-Danube conditions are not being treated solely as a short-lived operational event. Maintaining reliable cooling-water access is becoming part of the investment required to preserve the availability of existing nuclear generation during severe hydrological stress.
