Bulgaria is considering new infrastructure around NPP Kozloduy after unusually low Danube levels forced the country’s first precautionary nuclear output reduction linked to the current hydrological conditions.
The government is examining construction of a new levee near the plant, intended to make the site less vulnerable 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 the country’s largest source of baseload electricity.
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 subsequently recovered somewhat, reducing the immediate risk of further curtailment, but the episode has highlighted the exposure of thermal and nuclear generation to increasingly variable water conditions.
The 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, while exports have been close to 30,000 MWh per day. Bulgaria therefore retained a sizeable system surplus even during the nuclear reduction.
Thermal availability is also improving. Maritsa East 2 unit 7 has returned after repairs were completed ahead of schedule, while unit 8 is expected back before the end of August.
The more important issue is longer term. Bulgaria’s consideration of permanent water-protection infrastructure indicates that low-Danube conditions are no longer 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 periods of severe hydrological stress.
