Hungary has switched off decorative lighting on Budapest's parliament building, the Buda Castle and Chain Bridge to save energy in a heatwave, disappointing some tourists but in a move welcomed by residents — and swarming mayflies.
City halls, factories and some churches across neighbouring Romania were also dimming lights, halting production and rationing electricity as authorities try to keep the country's only working nuclear reactor running during a drought.
A prolonged heatwave and record-low water levels on the Danube forced Hungary to largely shut down its sole nuclear plant, which uses river water for cooling, stretching power supply capacity to its limits over the past week.
On Thursday, temperatures were scaling 40 degrees Celsius to 42 C (104 degrees Fahrenheit to 108 F), well above average for August.
"I'm very disappointed because I come to Budapest maybe once in a lifetime and I climbed up the hill yesterday and I was waiting for the building to be lit," Silke Schneiders, a German tourist, said. "I was going on a river cruise as well by night, and all the lights and the bridge were pitch black."
But many Hungarians said it was the right decision as they were having to cut power consumption after a government appeal to ease pressure on the grid.
"Obviously, it sucks, but I can appreciate and be grateful for what I have here," said tourist Benjamin Thomas Tucker.
Romania's capital city Bucharest dimmed street lighting by a third on Wednesday evening and switched off lighting at night at landmark buildings and museums to save power. Other cities are enforcing similar measures.
"It seems we've reached this point due to poor decisions, given the climate crisis we've faced for decades," said Mircea, 25, a food engineer, in front of the dark city hall.
However, Budapest's mayflies, a protected species swarming in huge numbers in the summer, would benefit from the darkness, said Gyorgy Kriska, associate professor at Eotvos Lorand University.
"Light pollution is dangerous for mayflies as they are drawn to the lamps and light at the riverbank. Switching off the lights is the best way to protect them," Kriska said.
Hundreds of thousands, sometimes millions, of mayflies emerge from the water and engage in a frantic rush to reproduce before they die within just a few hours.
