Europe’s aggressive blueprint to bolster its nuclear fleet for the energy transition is jeopardized by a lack of key components: skilled workers.

Atomic power producers in France, the UK and Sweden are having trouble finding the hundreds of thousands of welders, engineers and planners needed for reactors they’re building now and ones they’re eyeing for mid-century.

That’s why representatives from Electricite de France SA and three subcontractors gathered recently in a classroom at the Lycee Polyvalent de l’Edit in Roussillon, a small town near the Saint-Alban nuclear plant in the Rhone valley. In a new recruiting initiative, they were pitching internships and job opportunities to about a dozen high-school students taking industrial maintenance courses.

“Every company is hiring, notably in the nuclear industry, even more now with the new reactor projects,” Morgane Robin, a recruiter for Dalkia EN, a maintenance unit of EDF, told the pupils. “We’re counting on you and on your teachers to raise your skills.”

Nuclear energy is on the verge of a renaissance after 25 countries, including more than a dozen in Europe, set a goal to help triple global capacity. Yet their follow-through is hampered by a labor shortage so dire some French companies hire back retirees, the UK government advertises industry careers in London Underground stations, and a Swedish university offers free sandwiches to students attending information sessions.

“Nuclear is exiting a long winter,” said Philippe Lanoir, president for industry and energy at France’s Syntec-Ingenierie business federation. “We’ll need trained resources to get projects off the ground. We don’t have much time to react.”

France finds itself lacking talent after EDF ended a decades-long building spree in the early 2000s, turning the industry into a dead-end career path. The workforce of about 220,000 is now aging out while potential replacements look elsewhere. The industry has outlined a plan to increase vocational training for laborers, technicians and engineers. Its target: Recruit 100,000 workers during the next decade.

Syntec, representing about 400 engineering firms, launched a teen-focused promotional campaign and is pushing to boost college and training programs.

President Emmanuel Macron wants EDF to build six reactors for an estimated €67.4 billion ($72 billion) and then plan for eight more. Those ambitions may be affected by ongoing legislative elections. Marine Le Pen’s National Rally party, which dominated the first round of voting, wants to go further than Macron by building 20 reactors in coming decades. The second round is Sunday.

Potentially, a quarter of the jobs created by EDF’s plans may go unfilled, Lanoir’s group estimates, as current employees retire and take their expertise with them, schools lag in training and young people choose more dynamic, headline-grabbing industries such as solar and wind.

That’s a recipe for lengthy construction delays and massive cost overruns - failings the industry already is notorious for. In addition, clean-energy target dates may be put at risk.

“Everybody wonders how we’re going to do all these new projects as we lack staff,” said Sebastien Cuquemelle, the former co-owner of engineering firm Probent, which was acquired earlier this year by construction group Eiffage SA.

EDF, which took 17 years to build its newest plant, identified lack of labor as the primary roadblock to carrying out the revival envisioned by Macron in 2022. That year, the company imported workers from North America to handle scores of reactor pipe repairs.

In the port of Cherbourg, where French nuclear submarines are built, Probent frequently offers retired welders and metal workers jobs in the shipyard and at the nearby fuel recycling plant run by Orano SA - which itself plans to build more facilities.

“Given that there’s competition for resources, some players are ready to offer pay increases that are bigger than in other sectors,” said Thomas Branche, executive vice president of nuclear and energy new build at French engineering firm Assystem SA. Right now, the nuclear industry is one of the most attractive in terms of wages, he said.

EDF’s needs extend beyond France. It’s building the UK’s Hinkley Point C nuclear project, but that’s been delayed by labor shortages and supply-chain issues, with the price tag ballooning to about £48 billion ($61 billion), adjusted for inflation.

The utility and UK authorities are also seeking to convince private investors to help finance a pair of reactors at Sizewell. The projects are part of the UK’s commitment to quadruple nuclear-power capacity by 2050.

Reaching that target is expected to require 123,000 people this decade, the government said. To help bridge the manpower gap, the government and industry - including EDF, BAE Systems Plc and Rolls Royce – are committing £763 million to boost apprenticeships and skills training.

“We are delivering the biggest expansion to nuclear power in 70 years and need a homegrown pool of talent that will fuel our nuclear ambitions,” said Amanda Solloway, the minister for energy consumers and affordability.

The government believes one choice place to find that talent is on the Tube. From February through April, the Victoria, Paddington and Charing Cross stations featured ads for the UK’s Destination Nuclear portal: “Whatever you do, you can do nuclear.”

The intended audience was people open to changing jobs. A campaign this fall will target younger people through social media and maybe TV commercials, a Destination Nuclear spokeswoman said.

The website advertises more than 1,500 opportunities and says starting a career “is easier than you think.” The roundabout paths taken by seven people - including a former National Health Service administrator and an ex-hospitality worker - serve as case studies.

The industry is holding skills boot camps for mid-career professionals around the UK. Weekslong programs to train health physics monitors and project controls planners were underway in June, with sessions for aspiring welders scheduled for July.

Sweden has six working reactors, and the government said it needs at least 10 more by 2045 to meet demand from the electrification of transportation and industries.

That necessitates hiring tens of thousands of workers, said Carl Berglof, the nuclear power coordinator.

“It would be strange for the educational system not to see the opportunities and address the issue,” he said.

State-owned utility Vattenfall AB, which operates five reactors, retrains current employees and recruits from other industries known for major infrastructure projects, Chief Executive Officer Anna Borg said.

It’s also collaborating with schools and universities to increase awareness. Uppsala University, north of Stockholm, organizes free lunches where academics pitch courses and careers in atomic energy to students.

Teachers also lobby colleagues in other departments to include the material in their courses, said Ane Hakansson, a professor of nuclear physics. Still, the nation only educates about 50 to 70 students a year specializing in nuclear engineering.

“It’s a bottleneck,” Hakansson said. “Some people say, ‘Let’s import workers from abroad,’ but that won’t be easy either as France, the UK and others have the same problem as us.”

With assistance from Rachel Morison, James Herron, Petra Sorge, Daniel Hornak, Kari Lundgren, Niclas Rolander and Heesu Lee.