Nano Nuclear Energy vs. Constellation Energy: Which Nuclear Stock is Better?

The nuclear power industry is seeing a resurgence, but these two companies are at different ends of the spectrum.

Published on Feb. 5, 2026

Got story updates? Submit your updates here. ›

The needs of big tech and the growth of artificial intelligence (AI) are driving a resurgence of nuclear power, as countries scramble to keep up with rising energy demand. Nano Nuclear Energy (NASDAQ: NNE) and Constellation Energy (NASDAQ: CEG) are two companies in the nuclear investment space, but they have very different profiles. Nano is a small-cap startup focused on micro-modular reactors, while Constellation is the largest private-sector energy company in the U.S. with a diverse energy portfolio including nuclear, natural gas, and renewables.

Why it matters

The nuclear power industry is poised for growth as the world looks to meet increasing energy demands, especially from the tech sector. Investors are looking to capitalize on this trend, but must weigh the risks and potential rewards of companies like Nano and Constellation.

The details

Nano Nuclear Energy, founded in 2020, specializes in micro reactors and portable nuclear batteries for remote industrial sites, military bases, and some space applications. Its micro-modular reactors (MMRs) are designed to be easier and less expensive to deploy than traditional reactors. Constellation Energy, on the other hand, has the largest fleet of nuclear power plants in the U.S. and also uses natural gas, geothermal, hydro, wind, and solar power to generate electricity.

  • Nano Nuclear Energy went public via an IPO in 2024.
  • Nano acquired its flagship Kronos MMR product in early 2025 after the previous owner, Ultra Safe Nuclear Corporation, went bankrupt.

The players

Nano Nuclear Energy

A small-cap startup founded in 2020 that specializes in micro-modular nuclear reactors and portable nuclear batteries.

Constellation Energy

The largest private-sector energy company in the U.S. that uses nuclear, natural gas, geothermal, hydro, wind, and solar power to generate electricity.

Got photos? Submit your photos here. ›

What they’re saying

“There's a lot to be excited about with Nano, as its niche market is expected to grow. However, it doesn't have a track record as a profitable company, and that's a big leap for many start-ups.”

— The Motley Fool, Analyst (nasdaq.com)

“Constellation has much more size and diversity. For example, if nuclear energy demand is reduced, Constellation can likely offset the revenue loss from its other energy sources.”

— The Motley Fool, Analyst (nasdaq.com)

What’s next

The judge in the case will decide on Tuesday whether or not to allow Walker Reed Quinn out on bail.

The takeaway

Investors must weigh the risks and potential rewards of investing in nuclear energy companies like Nano and Constellation. Nano's micro-reactor technology is exciting, but it lacks a proven track record, while Constellation's diversified energy portfolio provides more stability but less upside potential.