Units at the Czech Dukovany plant generate more power in mild winter weather than in freezing conditions

Units at the Dukovany Nuclear Power Plant are generating more power in the current mild winter weather than they would in freezing conditions. Operators can maintain the optimum cooling-circuit water temperature while using minimal energy, the plant’s spokesperson Jiří Bezděk told the Czech News Agency (ČTK) today. Such conditions usually occur in spring and autumn, he said.

The plant was able to switch off the winter screens on its cooling towers, which help protect them from freezing, as early as 2 March this year. Unit output, which averages around 500 megawatts (MWe), increased by one MWe as a result. “With three generating units currently in operation, switching off the winter screens in March will increase output by 2160 megawatt-hours,” plant director Roman Havlín said. That amount of electricity is equivalent to the annual consumption of approximately 620 households.

The ideal water temperature in the cooling towers is between 12.5 and 14.5 degrees Celsius, corresponding to an air temperature of between zero and two degrees Celsius. At lower temperatures, energy workers must take measures to protect the massive reinforced-concrete cooling towers from freezing. These measures partly raise the temperature of the cooling water and also increase electricity consumption. “They include, among other things, switching on the so-called winter screens, bypassing cooling water directly into the basin, or increasing the water flow through the equipment,” the plant’s spokesperson said.