Zap is taking a unique approach to fusion power known as sheared-flow-stabilized Z-pinch. Instead of using magnets or lasers to squeeze the plasma, it sends a bolt of electricity through a plasma stream. That current generates a magnetic field that compresses the plasma — the pinch — and ends up with fusion. The company had been studying the phenomenon through a series of devices at its facilities in Washington state.

The demonstration device stands about a story and a half tall, and the liquid bismuth-lined reaction chamber inside is the size of a domestic water heater

To remain on track to a commercial power plant, Zap needs to hit three milestones: First, it needs to be able to generate high-voltage pulses frequently and continuously. A few weeks after it was turned on this summer, Century fired 1,080 consecutive pulses. So far, so good.

The next step is to demonstrate the technology for the Department of Energy, running the device for more than two hours by firing at 10-second intervals to generate at least 1,000 plasma pulses. Ultimately, to operate as a commercial power plant, Zap’s reactor will need to spark 10 pulses per second for months on end.

I wish they shared more details on what the plasma is. Straight duterium? A mix of duterium and tritium?