2 Green Flags and 2 Red Flags for Nuclear Stocks After This Year's Sell-Off

NextEra Energy (NYSE: NEE) recently agreed to buy Dominion Energy (NYSE: D), at least partly to gain access to fast-growing data center demand. The deal will also give the combined company material scale in the U.S. nuclear power sector. NextEra is leaning into what it sees as key long-term trends, with demand for electricity in the United States expected to increase by 60% between 2025 and 2045.​​

If you are an investor, nuclear power presents a huge opportunity. But all opportunities come with risk, as highlighted by the pullback in the nuclear power sector in 2026. Here are two green flags to consider and two red flags to contemplate before you jump into the nuclear power sector.

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2 green flags

Electricity demand is the primary reason for favoring nuclear power stocks as investments. As noted above, electricity demand in the United States is expected to rise 60% between 2025 and 2045. The key to understanding that figure, however, is that demand rose by only 10% in the previous 20-year period. This is a step change in demand, and renewable energy sources like solar and wind simply won't be able to meet it all because they are intermittent. Nuclear is always on baseload power.

A significant portion of the expected demand is coming from new technologies, such as electric cars and artificial intelligence. There are early signs of demand for nuclear power, as companies like Constellation Energy (NASDAQ: CEG) ink deals with AI companies to reopen shuttered nuclear power plants or keep ones slated for closure open. That said, there are currently 438 operable reactors in the world, with 417 actually operating, according to nuclear fuel supplier Cameco (NYSE: CCJ).

So there are only a limited number of opportunities for growth within the existing nuclear power fleet. The big opportunity, and the second green flag, is new construction. There are currently 77 reactors under construction, most of which are in Asia. But companies like Oklo (NYSE: OKLO) and NuScale Power (NYSE: SMR) are looking to push nuclear technology to new levels, with small modular nuclear reactors (SMRs). And government support for SMRs and nuclear power, more broadly, could help initiate a new building boom.

2 red flags

As with any new technology, however, investors need to watch the cash. For example, Oklo and NuScale are both money-losing start-ups. The idea of SMRs is exciting, but much more work remains before they become a significant factor in the industry. And while these two stocks rose dramatically on news that the U.S. government was providing funding to nuclear start-ups, they each fell back to earth when it became clear that neither company was on the verge of profitability.

That's really two red flags in one example, since new technology and funding are both issues that need monitoring. However, funding isn't just an issue for start-ups. Building a large-scale nuclear power plant is an expensive endeavor (it is also time-consuming and difficult, but put that aside for now). So money is a very big problem for any company that wants to build out its nuclear power fleet. This is part of the reason why NextEra is buying Dominion. The combined company will not only be number two in U.S. nuclear but also the largest publicly traded utility in the United States and the world. That is likely to provide it with advantaged access to capital markets.

That said, investors are always making trade-offs between risk and reward. And something that investors need to watch carefully, making it red flag number two, is valuations. Money-losing start-ups are notoriously difficult to value, but Constellation Energy, even after a sell-off, has a price-to-earnings ratio of 25x. The average utility's P/E is roughly 19x. Nuclear fuel supplier Cameco has a P/E of 157x, but it operates a commodity-driven business, which can lead to outlandish valuation figures at times. NextEra's P/E, notably, is roughly 17x, making it look relatively cheap, but it is far from a pure-play in the nuclear power space.

Even a good business can be a bad investment if you pay too much for it. And mercurial investors have proven that moods can swing quickly in the nuclear power sector. You need to tread with caution and make sure you are comfortable with what you are paying to own a nuclear power stock.

Huge opportunities and huge risks

Nuclear power has a lot going for it, but there are always risks that you have to consider when buying a stock. Right now, growing electricity demand and nuclear power plant construction are two green flags to watch. But red flags like funding for hugely expensive reactors and new technology development, as well as sector valuations, need to be watched as well, as they may temper your enthusiasm for a particular stock.

Reuben Gregg Brewer has no position in any of the stocks mentioned. The Motley Fool has positions in and recommends Cameco, Constellation Energy, and NextEra Energy. The Motley Fool recommends Dominion Energy and NuScale Power. The Motley Fool has a disclosure policy.