AI Investing Glossary

What is an SMR and why do AI companies care?

An SMR, small modular reactor, is a nuclear reactor design small enough to be factory-built in modules and deployed incrementally, rather than constructed as a single giant plant. AI companies back SMRs because data centers need large, constant, carbon-accountable power, which nuclear provides and intermittent sources cannot match alone.

Why it matters for AI investors

SMR developers are a long-horizon, pre-revenue corner of the AI power trade: agreements with AI buyers validate the technology path, but first commercial power remains years away, so these stocks trade on milestones and sentiment rather than earnings. The nearer-term nuclear beneficiaries are existing operators restarting or expanding conventional capacity.

Tracked stocks in this layer

The largest names in the Power & Energy category, ranked by market cap:

Market data as of the close on . Prices are end of day, not live.

Related reading

Frequently asked questions

When will SMRs actually power data centers?

Developers target first commercial units around the turn of the decade, with regulatory approval, supply chains, and first-of-a-kind construction the main risks to those dates. The AI-buyer agreements announced so far are mostly framework and offtake commitments for future capacity rather than power flowing today, which is worth keeping in view when reading headlines.

Related terms

See how this fits the whole picture in the Start Here guide, or browse the full glossary.