Fusion may still sound like science fiction— but it might not be for much longer. With AI pushing demand for clean power to new highs, a breakthrough may finally be close.

For Decoded, YC General Partner Gustaf Alstromer traces the history of fusion, the physics behind it, and the engineering challenges that stalled it for nearly a century.

He also looks at how Helion is approaching the problem differently, as they develop a new fusion system expected to deliver power to Microsoft by 2028.