For hard-tech startups, manufacturing is an expensive endeavor. Now, Thea Energy has a head start thanks to a grant from the Department of Energy.

The fusion energy startup told TechCrunch on Monday that it received a $20 million grant from ARPA-E to help manufacture its modular high-temperature superconducting (HTS) magnets.

HTS magnets are expensive but important components in any magnetic confinement reactor, one of two main ways startups are trying to harness fusion energy for commercial purposes. In magnetic confinement reactors, powerful magnetic fields contain and compress the plasma, helping to heat the particles until the fuel can fuse and release large amounts of energy.

Thea’s reactor is based on a design known as a stellarator. Stellators look like internal tubes that have been twisted and compressed in ways that help confine the plasma more effectively. Most stellarators use magnets built to mimic those twists and turns, making them expensive to manufacture.

To minimize manufacturing costs, Thea uses fewer variants. The 12 large magnets that do the heavy lifting are made from four different templates, and the 300+ smaller magnets used to adjust the plasma are all identical. They are arranged around the periphery of the reactor, similar to how pixels are arranged on a computer screen.

The small magnets are controlled by software, an arrangement that should allow for more lenient construction tolerances, which could reduce costs, Thea says.

Thea is among the best-funded fusion energy startups, having raised $100 million in May on top of a $20 million Series A it raised in 2024. Like many of its peers, Thea has plans to build a commercial-scale fusion power plant in the mid-2040s.