Fusion Power Probably Won’t Be Cheap, Sorry

Fusion power has this almost mythical status in clean energy circles—limitless, zero-emissions electricity that could finally break our fossil fuel addiction. But a new study out in Nature Energy throws some cold water on the hype. Even if we get fusion plants running, the electricity they produce might stay stubbornly expensive.

We’ve seen this story before with other technologies. Lithium-ion batteries dropped about 90% in price since 2013. Solar modules? Down roughly 23% every time global capacity doubles. But not everything follows that curve. Nuclear fission, for example, has a miserable experience rate of just 2%—meaning costs barely budge as we build more.

The researchers behind this new paper wanted to figure out where fusion might land. They interviewed experts and looked at three factors that historically predict how fast a technology gets cheaper: unit size, design complexity, and how much customization each installation needs.

Fusion plants are going to be big. Think coal plant or fission reactor big. That alone drags down the experience rate. They’ll need less customization than fission plants—regulations should be simpler—but more than something like a solar panel. And complexity? The experts were nearly unanimous: fusion is off-the-charts complicated. One researcher literally said it was off the scale they provided.

The final estimate lands between 2% and 8%. That’s better than fission but nowhere near the 8% to 20% that many energy models currently assume. It means we’d need massive deployment over a long time before costs come down meaningfully. And that’s assuming we can even build the first few plants without bankrupting everyone.

Lingxi Tang, one of the study’s authors, raises a fair question: with the US spending over $1 billion on fusion in FY2024 and private funding hitting $2.2 billion between July 2024 and July 2025, is this really the best use of money for decarbonization? It’s a valid point when solar and wind are already cheap and getting cheaper.

Of course, predictions about unbuilt technology are shaky. Egemen Kolemen from Princeton Plasma Physics Lab points out that in 2000, analysts thought solar would stay expensive. Then China went all in and prices cratered. “We haven’t built the thing yet, so we don’t know,” he says.

Still, I think it’s worth being skeptical about fusion’s economic prospects. The physics is hard enough. The economics might be even harder. And betting billions on a technology that might never compete on price feels like a gamble we should at least acknowledge.