City Labs Plans Second Nuclear Demo Flight

City Labs is planning a second nuclear-powered demonstration flight as early as next year. The company's CEO, Peter Cabauy, told Payload the new demo will test a Tritium-powered radioisotope heating unit (RHU).

This follows the company's first successful demo, called BOHR, which launched on SpaceX's Transporter-17 rideshare mission in July. BOHR demonstrated a Tritium-powered betavoltaic battery designed to provide energy independent of solar power.

The Next Step: Surviving Lunar Night

The upcoming demo aims to prove a technology critical for the Moon. The RHU is intended to provide payloads with a source of heat. Ultimately, the goal is to help lunar payloads continue operating throughout the frigid lunar night, which lasts two weeks.

Cabauy described the plan as repeating their previous success but changing the technology. He called it taking it to the next natural level. When combined, the betavoltaic batteries and RHUs could enable lunar-surface missions to survive and operate through the entire lunar night.

This capability addresses a major economic hurdle. Missions to the Moon can cost hundreds of millions of dollars, only to die after sunset. Nuclear energy and heat sources could enable longer-duration missions. For comparison, NASA's nuclear-powered Curiosity and Perseverance rovers have operated on Mars for 14 Earth years and five Earth years, respectively, and are still running.

Scaling Up for Demand

The technologies are designed to scale. Each individual battery or RHU is small, weighing only a few grams and giving off microwatts of power or heat. They can be stacked together to collectively provide the right amount of warmth or power for a customer's specific needs.

Since the July launch of BOHR, City Labs has seen demand for its nuclear batteries spike. Cabauy expects a similar market reaction after the 2027 demo. To meet this demand, the company has organized its supply chain to start producing batteries and RHUs at scale. It has also secured access to Tritium-based fuel from US and international sources.

The commercial push is driven by a clear problem. Cabauy said the goal is to ensure missions to the Moon don't end prematurely due to preventable circumstances like freezing in the dark. He stated that a lunar economy requires heat, and there is no Moon base or permanence without heated sensors that can run through the night.

A Favorable Regulatory Climate

The company's timing is supported by NASA's focus. City Labs is experiencing a commercial renaissance largely thanks to NASA's heightened focus on establishing a permanent lunar presence. This presence will necessarily require nuclear power and heating sources.

NASA's push to return humans to the Moon before the end of the decade has helped clear a regulatory pathway for commercial nuclear launches. With one mission already completed, Cabauy said he expects City Labs to fly its second demo without any regulatory speed bumps.