Electricity prices in southeastern Europe exceeded EUR 700/MWh. The most expensive 15-minute periods were around 8 pm

Drought and heat reduced generation at nuclear and hydroelectric power plants in the Danube basin, while prices on exchanges in the region surged by 50 to 100 percent compared with previous weeks. The peak of EUR 717/MWh was reached on 3 August on Slovenia’s BSP SouthPool exchange. However, an analysis of seven exchanges shows that price spikes were not evenly spread, but concentrated in four 15-minute trading intervals between 19:30 and 20:30, when photovoltaic generation ends while demand has not yet fallen.

The phenomenon in these markets was caused by a confluence of circumstances unprecedented in the region in recent years. According to an analysis by Balkan Green Energy News, which processed day-ahead market data from seven exchanges for the period from 31 July to 6 August, Hungary’s Paks nuclear power plant cut output by 90 percent due to a shortage of cooling water from the Danube. Of its installed capacity of 2,000 MW, it was generating around 230 MW. Romania’s Cernavodă reduced output by half, while Slovenia’s Krško cut output by a fifth due to the high temperature of the Sava River.