Nuclear Monitor #940
Jan van Evert, reporter WISE-Netherlands
Heat waves and prolonged drought have caused serious problems for the nuclear energy sector in several European countries this summer.
In France, a combination of extreme drought and a recurring jellyfish invasion have reduced the nation’s nuclear energy production by twenty percent. A record number since 2015. eight reactors have been shut down completely and another five partially. Fortunately, France also produces a large amount of solar power so that no shortages are to be feared.
In Hungary, the 2000 MW Paks nuclear power plant has come close to a full shutdown, as a critical lack of water flowing from the Danube threatened the facility’s ability to cool its reactors. The plant consists of four reactors, only one is still operational. That is a serious problem because the Paks plant generates nearly half of the country’s total electricity supply.
The Hungarian government announced on August 12th that it was taking action to ensure the supply of cooling water to the reactors. The longer-term measure is to build a bottom sill in the riverbed, and the water level will be temporarily raised with two barges sunk in appropriate places in the river. The cost of the measures is estimated at about $ 10 million.
Further downstream the river Danube, in Romania, the river’s water flow has fallen to its lowest in decades at 1,400 cubic meters per second. This is less than a third of what is typical for this time of year. Romania has taken the second unit of the Cernavoda nuclear power plant offline. Electricity company Nuclearelectrica had already shut down unit 1 and disconnected it from the National Energy System on July 28th.
To redirect water flows, the energy ministry used explosives to remove a rock obstruction, dredged the river bed and sank four rock-filled barges, reporting that this raised water levels around unit 2 of the plant by four centimetres. “Based on forecasts available at the moment this development allows for the necessary conditions for the reactor to function for at least the next nine days,” the ministry said on August 9th after sinking the rock-filled barges.
These measures appeared in vain because on the morning of August 12th, the water level in the Danube had reached 182 centimetres; three centimetres short of the 185- centimetre mark required for the normal operation of the Cernavoda plant. Nuclearelectrica announced it would begin the controlled shutdown of unit 2 on August 13th. Cernavoda is the only nuclear power plant in Romania and consists of two 650 MW reactors, generating about one-fifth of its electricity. In Moldova, which relies heavily on imported electricity, including from Romania, the authorities have urged citizens to voluntarily reduce electricity usage during peak hours.
In Bulgaria, the energy ministry said it would “preventively lower the output of Kozloduy’s Unit 5 by some 120 MW on August 21st” to ensure the plant’s safe operation. It’s the first time in the plant’s 52-year history that extreme weather conditions forced to reduce the output. Unit 5 has a capacity of just over 1,000 MW.
Sources:
https://futurism.com/science-energy/europe-heat-wave-water-nuclear-plants
https://www.world-nuclear-news.org/articles/romanian-plant-taken-offline-as-hungary-moves-to-keep-paks-operating
https://www.aa.com.tr/en/greenline/climate-change/bulgarias-kozloduy-nuclear-plant-cuts-output-because-of-danube-drought/1831480
