Almost exactly one year ago, NuScale Power made history as the first of a new generation of nuclear energy startups to win regulatory approval of its reactor design just in time for the Biden administration to begin pumping billions of federal dollars into turning around the nations atomic energy industry.

But as mounting costs and the cancellation of its landmark first power plant have burned through shrinking cash reserves, the Oregon-based company is laying off nearly a third of its workforce.

At a virtual all-hands meeting Friday afternoon, the company announced the job cuts to remaining employees. HuffPost reviewed the audio of the meeting. Two sources with direct knowledge of NuScales plans confirmed the details of the layoffs.

By Friday evening, NuScales stock price had plunged more than 8% as investors sold off shares. NuScale did not respond to a call, an email or a text message seeking comment.

In a press release issued Monday, the company confirmed it had laid off 154 individual employees, or 28% of its full-time staff. Sources told HuffPost on Friday the cuts affected as much as 40% of the total workforce. The spokesperson who sent HuffPost the announcement Monday morning did not respond to an email asking how many part-time workers and contractors the firm has let go.

Surging construction costs are imperiling clean energy across the country. In just the past two months, developers have pulled the plug on major offshore wind farms in New Jersey and New York after state officials refused to let companies rebid for contracts at a higher rate.

But the financial headwinds are taking an especially acute toll on nuclear power. It takes more than a decade to build a reactor, and the only new ones under construction in the U.S. and Europe went billions of dollars over budget in the past two decades. Many in the atomic energy industry are betting that small modular reactors shrunken down, lower-power units with a uniform design can make it cheaper and easier to build new nuclear plants through assembly-line repetition.

The U.S. government is banking on that strategy to meet its climate goals. The Biden administration spearheaded a pledge to triple atomic energy production worldwide in the next three decades at the United Nations climate summit in Dubai last month, enlisting dozens of partner nations in Europe, Asia and Africa.

The two infrastructure-spending laws that President Joe Biden signed in recent years earmark billions in spending to develop new reactors and keep existing plants open. And new bills in Congress to speed up U.S. nuclear deployments and sell more American reactors abroad are virtually all bipartisan, with progressives and right-wing Republicans alike expressing support for atomic energy.