Fusion power has the potential to rewrite trillion-dollar energy markets, but first, startups have to prove their designs will work and won’t be too costly. Neither is easy, especially when considering the massive magnets and lasers used in many designs must be installed with millimeter precision or better.
Fusion startup Thea Energy says it’s pixel-inspired reactor and specialized control software should be able to generate power without requiring the same level of perfection.
“It doesn’t have to be as good to begin with,” Brian Berzin, co-founder and CEO of Thea Energy, told TechCrunch. “We have a way to tune out imperfections on the back end.” That margin of error could give Thea a leg up on the competition.
Fusion power plants promise to deliver gigawatts of clean power to the grid, but material and construction costs threaten to make them uncompetitive with cheap solar and wind. By building a power plant first and ironing out the kinks in software, Thea could help bring the cost of fusion power down dramatically.
This animation shows how Helios can be disassembled for maintenance. Image Credits:Thea Energy
But first the company has to build a working prototype. Today, Thea is publishing the details of its design, including the details of the physics that underpin it. The startup shared the paper exclusively with TechCrunch.
Thea is building a unique take on the stellarator, a specific type of reactor that uses magnets to whip the plasma fuel into shape. Magnets are one of the two main ways that fusion scientists keep plasma heat and confine plasma until fusion reactions occur. The other, known as inertial confinement, uses lasers or some other force to squeeze small fuel pellets.
Most stellarators are built with magnets that looks at home in a Salvador Dali painting. But Thea’s design uses a dozen larger magnets and hundreds of smaller ones to create what you might call a “virtual” stellarator.
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In a typical stellarator, the magnets are built to follow the contours of a shape that’s intended to work with the quirks of plasma, helping to confine it for longer using less power than tokamaks, which use a series of identically sized and shaped magnets. Yet stellarators have one major disadvantage: the irregular shape makes mass manufacturing magnets challenging.
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