SK Group is reportedly seeking to acquire a sizeable stake in TerraPower, a US nuclear power startup backed by Bill Gates, as part of its investment push in the carbon-free energy sector such as electric vehicle batteries and hydrogen.

According to local daily Chosun Ilbo on Tuesday, the nation’s third-largest conglomerate is in talks to purchase a 10 percent stake, worth $15.4 million, in TerraPower, from India’s Reliance Industries.

“Nothing has been decided yet,” an SK spokesperson said. “We have considered investing in small modular reactors and TerraPower is one of the options.”

TerraPower, co-founded by Gates about 15 years ago, develops smaller advanced reactors that are faster and cheaper to build than conventional reactors while producing less waste.

Its advanced nuclear design, called Natrium, uses liquid sodium as a cooling agent instead of water, which has a lower risk of explosion.

Natrium plants, running on high-assay low-enriched uranium or HALEU, are also considered a more advanced carbon-free technology. But the fuel is not yet available on a commercial scale.

TerraPower plans to build its first demonstration reactor in Kemmerer, Wyoming, by 2028, with the potential to expand the capacity from 345 megawatts to 500 megawatts.