After years in the wilderness, the time was right to become a nuclear startup.
“For the first five years, I was telling people I was working on nuclear, and I had to convince them, ‘Hey, here’s why nuclear is important,'” Last Energy founder and CEO Bret Kugelmass told TechCrunch. “Now everyone just comes to us and says, ‘Oh, of course nuclear is an important part of the solution.'” I’m like, Okay, great, I’m glad everyone is catching up. ”
Last Energy is building small modular reactors, compact nuclear power plants that can be produced in large quantities to cut costs. The company’s reactor is designed to generate 20 megawatts of electricity, enough to power about 15,000 homes.
There’s a lot of momentum. Last Energy just completed a $100 million Series C led by Astera Institute with participation from AE Ventures, Galaxy Fund, Gigafund, JAM Fund, The Haskell Company, Ultranative, Woori Technology, and others.
The company joins a number of nuclear startups that have raised funding in recent months, fueled by data centers’ insatiable demand for power. Google-backed X Energy raised $700 million last month, and Antares raised $96 million two weeks ago. And in August, Arlo Atomics raised $100 million to build a prototype reactor.
What sets Last Energy apart from its competitors is its approach. The company uses an older reactor design developed by the government decades ago. An initial design for a pressurized water reactor was built for the world’s first nuclear-powered merchant ship, the NS Savannah. The ship’s power plant was about one-tenth the size of Rust Energy’s planned commercial reactor. Kugelmas said the company’s latest design should be able to generate 20 megawatts of power.
However, the company started small. First, Rust Energy is building a 5-megawatt pilot reactor on property leased from Texas A&M. Kugelmas said the new funding will fully fund the pilot project and help the company begin delivering its first commercial product. Last Energy expects to commission a pilot reactor next year, with a 20-megawatt commercial-scale unit in production in 2028.
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The Last Energy startup’s reactors are not designed to be serviceable during their lifetime. Instead, Last Energy permanently encases each core with 1,000 tons of steel. Kugelmas estimates the metal will cost about $1 million. “Most people think concrete is cheaper,” he says. “But that’s not the case with nuclear-grade concrete.”
The reactor arrives on site fueled by six years’ worth of uranium. There are no through holes to break through the steel walls, except for electrical and control connections. Heat from the fission reaction warms the steel, and water flowing through the outer pipes collects that heat to turn the steam turbine.
At the end of the reactor’s operating time, Last Energy will leave the reactor on site and the steel chamber will act as a waste cask, eliminating the need for separate disposal.
It is hoped that this approach and advances in manufacturing will lower the price of nuclear power. Kugelmas declined to say what the price would be, instead pointing to other industries that cut prices in half for every 10-fold increase in production.
“I don’t think we’re going to see much better results in the nuclear sector because there’s always extra fixed costs in terms of some of the special regulations in the nuclear sector, but we’re seeing that trend,” he said. “We don’t think in units of one or two, we think in units of tens of thousands.”
