A grid failure caused a brief power outage in North Macedonia in the early hours on Sunday, May 18. Disruptions at the affected 400/110 kV transformer stations were triggered by high voltage levels in the grid, caused by low consumption, typical for nighttime hours and weekends at this time of year, according to a statement by the country’s transmission system operator, MEPSO.

MEPSO said its teams restored normal electricity supply in about an hour and were working to fully normalize the stability of the power system.

According to the update, grid instability caused by low consumption at nighttime and on weekends is a problem shared by almost all transmission system operators in the region and around Europe.

Bulgaria’s energy minister: Bulgaria played the crucial role in stabilizing North Macedonia’s grid

At the same time, Bulgarian Minister of Energy Zhecho Stankov said that a grid failure had affected several countries in Southeast Europe, though not Bulgaria. He added that his country’s balancing facilities were crucial in stabilizing North Macedonia’s grid, restoring supply, and preventing the crisis from spreading further. In Bulgaria, the Electricity System Operator (ESO) is responsible for the transmission network.

He claimed Serbia and Croatia have also experienced problems due to a lack of balancing facilities. “The colleagues from Serbia also had certain difficulties in the morning hours, and we managed to balance them out,” Stankov stated.

EMS has denied that any disruptions or outages occurred in Serbia

However, Serbia’s transmission system operator Elektromreža Srbije (EMS) told Balkan Green Energy news that the country’s grid did not experience any disruptions or outages and that there was no need for assistance from Bulgaria. EMS said it would not specifically comment on the Bulgarian minister’s statement because it was unclear what it was referring to.

In its reply to Balkan Green Energy News, EMS underscores that there were no consequences for the transmission system of the Republic of Serbia, explaining that EMS, at the request of MEPSO, to facilitate the repairs in North Macedonia, temporarily shut down the 400 kV transmission line between the Vranje 4 transformer station and the North Macedonian border.

Renewables had no share in the problem, according to Stankov

Stankov also stressed that solar power plants did not play a role in the crisis, unlike in Portugal and Spain in late April. The grid failure occurred in the early morning hours and amid low renewable energy generation, he said, adding that “renewable energy had no share in the problem.”

Bulgaria plans to build three new pumped storage hydropower plants

Bulgaria’s system remained stable thanks to its generating and balancing capacities, in Stankov’s view. He told the press that the country possesses 90% of all the reactive energy compensation capabilities in Southeast Europe.

Bulgaria is working with the European Investment Bank (EIB) to build at least three pumped storage hydropower plants in the Rhodope region, aimed at further enhancing regional grid resilience, Stankov pointed out. The minister vowed to keep the country’s grid on standby to support other regional networks in need of stabilization.

Stankov revealed that one such project is being developed for the Vacha dam. The other two pumped storage hydropower plants are planned to be built on the Dospat and Batak dams.