French power utility EDF will accelerate its climate adaptation plan for its nuclear fleet after extreme hot weather caused record disruptions at French nuclear plants this summer, EDF executive Xavier Ursat told Reuters on Tuesday.

More than half of France's electricity supply comes from nuclear plants that draw on rivers or estuaries for cooling "We will speed up the ADAPT schedule.

We were comfortable this summer but it showed us we need to accelerate," Ursat told Reuters on the sidelines of a press event at EDF's research lab EDF's nuclear fleet faced environmental restrictions this year at levels more than four times the previous record with over 13 terawatt hours lost by October 7, EnergyScan data showed Some reactors remain affected by low river levels A faster adaptation programme would increase upfront costs and require changes to the company's reactor maintenance schedule Many of the reactors affected by heatwaves return most cooling water to rivers at slightly higher temperatures, triggering environmental restrictions The adaptation plans will add cooling towers that use air to cool a small stream of dischargeable water from the main system, returning it to the river at a lower temperature The French court of auditors previously pegged the cost of adding new cooling towers at €500 million ($559.6 million) per reactor, which accounts for a large chunk of the €8.7 billion adaptation budget EDF set out in June EDF is also planning other climate adaptations, including discharge basins to reduce river water temperatures during heatwaves