The energy ministry is weighing five technical fixes for the Kozloduy nuclear plant, while the Danube stays critically low, energy minister Iva Petrova said. Carrying out the fixes will take about a year.

Petrova spoke at the seventh Sofia Economic Forum, organised by the Delphi Economic Forum at Sofia Balkan Palace.

"We have a set of five technical options that we are working on. We still have to weigh the costs and benefits and then decide," the minister said.

In the summer, the plant's reactors ran at reduced output for the first time in its history because the river was so low. The ministry then ran more studies and drew up steps that Petrova says are technically complex.

The minister believes the Danube situation is still a challenge with no precedent in history. She said the plant coped more than well. "What got us through this situation was the plant's own design, and the engineers who watched it round the clock," Petrova said.

Petrova said Bulgaria got through the crisis because Kozloduy, the coal plants, renewable energy and battery storage kept working. This also let Bulgaria support the wider region.

The minister added that the Vertical Gas Corridor is an example of the regional co-operation and solidarity needed given today's geopolitical challenges.

She said nuclear power remains Bulgaria's firm choice. The country has experience and ambitions in the field, and safe operation of the existing units is an unconditional priority.

Work on new units at the Kozloduy site is also continuing under an updated road map. The Belene nuclear plant is an asset of the energy system, and a strategic decision on it is due. The ministry is also working on small modular reactors.