One of the UK’s most senior civil servants, Alex Chisholm, has been revealed as the new UK chair of the energy company EDF, after having previously run the department that struck a deal for it to build a new nuclear power station. Chisholm was permanent secretary at the Cabinet Office, and before that led the business department, which worked on the government deal for EDF to go ahead with the Hinkley Point C nuclear plant in Somerset. The agreement was struck in 2016 with UK bill payers bearing the cost of the construction over a 35-year period. The long-delayed project’s costs have soared from an estimated £18bn to at least £31bn and it is due to be completed in 2031 – about 14 years after EDF thought it would be up and running. The French state-owned company is a specialist in nuclear power, and one of the “big six” energy providers that have been criticised for huge profits during the energy crisis sparked by the war in Ukraine. Chisholm’s departure is one of a number of high-profile exits from the civil service before a likely change of governing party. Alex Aiken, a former longstanding head of government communications, recently left Whitehall for a job as an adviser on communications to the government of the United Arab Emirates. There is also speculation about the future of Simon Case, the cabinet secretary and former royal aide installed by Boris Johnson, given incoming prime ministers often want their own preferred candidate in the job. Chisholm’s EDF role was approved by the watchdog on post-government jobs, known as the Advisory Committee on Business Appointments. But the watchdog said he must wait three months after departing government to take up the job and observe a ban on lobbying the government or involvement in negotiating government contracts for two years after leaving office. The watchdog said: “In 2016, his department was responsible for the decision on finalising the first contract for difference [a pricing mechanism], with respect to EDF and the construction of Hinkley Point C. However, this was ultimately a decision for the secretary of state and followed the 2014 approval from the European Commission and was based on terms agreed then, 10 years ago. “Significantly, due to the period of time that has elapsed, the committee did not consider Sir Alex could reasonably be seen to have influenced this decision in anticipation of an offer of work a decade later.” Chisholm said his appointment came “at a time of great change and opportunity in the energy sector”. “EDF continues to invest in nuclear, wind, solar and battery infrastructure to offer customers secure, clean and affordable electricity,” he said. “I look forward to getting to know all parts of the company, and to helping EDF serve the needs and priorities of the UK.” Simone Rossi, EDF’s UK boss, said: “Sir Alex brings great private and public sector leadership, governance and regulatory experience that can help steer the company’s efforts to help Britain achieve net zero.”