Atom Power Inc. has raised $3 million in a private equity and options offering, according to a filing Wednesday with the Securities and Exchange Commission.

The money came from three investors, according to the filing.

The Charlotte-based energy startup secured a large investment earlier in the year from Siemens. Atom Power did not disclose how much the investment was worth.

Atom Power was founded in 2014 for the purpose of revolutionizing commercial and industrial power distribution through the development of solid-state switching technology.

The company developed the first commercially viable solid-state circuit breaker.

Its CEO is Ryan Kennedy. He previously was a project manager for W.B. Moore Co. in Charlotte and has a degree in electrical engineering from UNC-Charlotte.

Companies relying on a Reg D exemption do not have to register their offering of securities with the SEC, but they must file what’s known as a Form D electronically with the SEC after they first sell their securities.