The Nuclear Startup Suing The NRC Is Asking For A Permit

Of all the startups in DOE’s Reactor Pilot Program, few have made less noise than Last Energy. It is a surprising change from the company that initiated the legal action questioning the scope of the Nuclear Regulatory Commission’s authority.

Now, Last Energy is asking for permission to build. The company filed the first part of a two-part construction permit application for a reactor project in Texas on October 20th, including requesting a limited work authorization (LWA) to start work on the facility foundation.

Who is Last Energy?

Founder and CEO Bret Kugelmass sold his Silicon Valley drone startup in 2017 and went all in on nuclear, starting a nuclear-focused podcast and a research institute before founding Last Energy in 2019.

The company’s board includes PayPal co-founder Luke Nosek and Ripple co-founder Jed McCaleb. Nosek’s Gigafund led Last Energy’s Series A, and McCaleb’s Astra Institute led a $100 million Series C last year.

As the American reactor developer iterated at its facilities in Texas, it locked in agreements for over 50 reactors at multiple sites across Europe

A boring reactor, on purpose

In an attempt to not fix what isn’t broken, their reactor design is as unoriginal as possible. The idea being that the more unoriginal a reactor design is, the easier it is going to be to license and operate.

The company is developing the PWR-20, which is a pressurized water reactor. It uses the same technology found in most of the American commercial reactor fleet, only it’s shrunk way down to only produce about 20 MW of electricity.

The fuel is equally unexciting, as it’s nearly identical to existing commercial low-enriched uranium (LEU) fuel pellets.

Similar to some of the other reactor development companies, the PWR-20 is designed to be built in a factory, shipped and assembled on site, and then shipped away after it’s used up. Last Energy says the reactor should last about 6 years before needing to be swapped out with a fresh core.

The fight with the NRC

In December 2024, Last Energy joined Texas and Utah in suing the NRC in federal court in Tyler, Texas. Last Energy was the only company among the original plaintiffs.

They targeted a 1956 rule that makes every reactor, no matter how small, a “utilization facility” that needs an NRC license. The Atomic Energy Act, they argued, only covers reactors that matter to the common defense or public health and safety.

“Building a new commercial reactor of any size in the United States has become virtually impossible,” the complaint said.

“This case will determine whether the NRC has the authority to charge hundreds of millions of dollars in fees and enforce billions in design changes in the absence of a safety or security concern,” Kugelmass told Reason. “Federal law is clear that it should not.”

By April 2025, Louisiana, Florida, Arizona’s legislature, Valar Atomics and Deep Fission had joined. The NRC moved to dismiss, then agreed to pause the case to “consider alternatives,” and the pause dragged on as the Trump administration ordered the NRC to rewrite its rules.

It should be no surprise to our readers that, as the NRC sheds months at a time from multiple different licensing schedules, the need for this lawsuit is coming into question.

The states that were signed on originally have all since filed to drop out, and the three reactor developers are reportedly weighing the next steps.

Slow to launch under DOE program

Last Energy was among the list of companies included in the DOE Reactor Pilot Program announced in 2025. Its project is sited at Texas A&M’s RELLIS campus and is called the PWR-5.

The company says the PWR-5 “uses the same physical reactor geometry as the company’s commercial PWR-20, with reduced fuel enrichment scaled for 5 MW of electrical output.”

The company was not among the DOE RPP participants that were able to obtain criticality by July 4th. Things can get a little awkward when the company that points the finger at regulations being the problem fails to deliver when the license is served up on a silver platter…

The company is nearly there with splitting atoms and its pilot design, as the DOE just approved its final safety analysis last month. Based on the timelines from some of the other companies that have obtained initial criticality, the company will likely achieve fission before the end of the year.