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May 20 (Reuters) - Power infrastructure firm SB Energy has confidentially filed for an initial public offering in the United States, it said on Wednesday, seeking to tap buoyant investor demand for new listings.

The IPO market is being driven by strong investor appetite for new offerings, as strong debuts of AI chipmaker Cerebras Systems CBRS.O and geothermal energy firm Fervo Energy FRVO.O boosted confidence among firms looking to tap public markets.

SpaceX unveiled its filing for an U.S. IPO on Wednesday.

SB Energy, which is backed by SoftBank Group 9984.T and OpenAI, develops large-scale power and data center infrastructure projects. Founded in 2019, the company is building several data center campuses to support rising demand tied to AI workloads.

In January, SB Energy announced its partnership with OpenAI as part of Stargate, a U.S. initiative to build next-generation AI and energy infrastructure.

The company has raised more than $18 billion in project capital and about 5 gigawatts of operating and under-construction energy portfolio, according to its website.

Confidential filings with the ⁠U.S. ​securities regulator allow companies to prepare ​for IPOs away from public market scrutiny.