It’s Time to Fall in Love with Nuclear Fusion—Again

If nuclear fission is associated with catastrophe, nuclear fusion is associated with delay and fraud. The joke about fusion, the synthesis of lab-grown stars, is that it’s always 10 years away. Or 20. Two lonely little isotopes, each with a pathetically low mass, are joined in holy electromagnetism in a massive artificial thunderclap. The remaining nucleus is smaller than the mass of the reacting nuclei, and the leftover mass is converted into light or heat by virtue of E = mc².

But what a utopia fusion seems to promise. Even with the jokes and equivocation and scams, it’s hard to be blasé about fusion’s stellar possibilities. So let’s indulge: Once fusion arrives, handmade suns, sources of unlimited clean energy, would—will—wipe out all human problems in a go. Our glorious pet stars, requiring only everyday hydrogen to whip up in a lab, won’t belch out carbon or radioactive waste. Instead they’ll exhale helium. Helium! That nonrenewable resource that’s already running low! Fusion, my friends, means not just infinite carbonless energy but more balloons.

Fusion will, of course, rescue the environment and decarbonize planet Earth in a cool afternoon. It will also—don’t stop me now—render irrelevant all the dead-eyed petroleum kleptocracies and trade wars and real wars waged in their name. When energy can be produced anywhere, with common household ingredients, authoritarian states will no longer derive despotic authority by accidents of geography, but will, whoosh, become secular democracies, the better to share fusion-reactor tips and tricks in happy glasnost and savor the collective joy and peace of a burning, flooding planet restored to tranquil shades of green and blue.

Even leaving aside the Shangri-la, fusion is exciting here and now. In December 2022—a solid century since physicists first identified fusion as the source of star power—American scientists at the National Ignition Facility in Livermore, California, where ignition is a way of life, had a breakthrough. They’d aimed 192 lasers at the inside of a pearl-sized gold can called a hohlraum, creating a radiation bath that heated up the outside of a peppercorn-sized spherical nubbin of hydrogen coated in diamond in the center of the little can.

Atoms flew off the nubbin, forcing it to implode at a speed of nearly 400 kilometers per second—about four times a bolt of lightning. This created 100 million-degree plasma under hundreds of billions of atmospheres of pressure—a gas so hot that electrons were freed from atomic nuclei. At 1:03 am on December 5, humanity hit the threshold for fusion ignition in a lab. The first flash of a handmade sun. Though it blinked out rather quickly, after less than 100 trillionths of a second, the reaction created 3.15 megajoules of energy when a mere 2.05 went in—a glorious 150 percent return on investment.

Somewhat discouragingly, the first thought of the US Department of Energy, which its publicity team spelled out in an admittedly cool sci-fi video, was that this fusion ignition could somehow “support” the government’s project to extend the lifespan of nuclear weapons. But never mind. With at least 30 private fusion companies across the world promising clean energy built on the Livermore breakthrough, the air is supercharged with Kennedy-era electrons of hope. According to a survey from the Fusion Industry Association, most of these companies believe fusion electricity will be on the grid by the 2030s. It’s time to fall in love with fusion as if we’ve never been hurt before.