TL;DR
Fusion, the process that powers the Sun, could someday give people clean electricity around the clock. The leaders of Germany and Japan just signed a joint pledge to chase it together, and their companies signed side deals on the unglamorous parts a power plant actually needs: miles upon miles of magnet tape, the heaters that warm the fuel, and the gear that handles it. One German start-up, Proxima Fusion, needs about 20,000 kilometers of that tape for a single demonstration machine, and is lining up a factory to make it at home. These are agreements to work together, not orders yet, and they put a date on the board: a German machine aiming to make more energy than it uses in the early 2030s, and a first power plant on the grounds of a retired nuclear station later that decade. For our odds on each step and the timeline of breakthroughs that leads to fusion power on the grid, subscribe.
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