Commonwealth Fusion Systems aims to complete SPARC through a $1 billion funding round; the demonstration reactor is 80% complete.

Commonwealth Fusion Systems is pursuing a $1 billion funding round to support completion of SPARC, its demonstration fusion reactor. Chief Executive Officer Bob Mumgaard said SPARC was approximately 80% complete.

The source frames the $1 billion as a funding-round objective tied to completing the reactor. It does not establish in the supplied excerpt that the round has closed or that the full amount has been committed or received.

No investors, valuation, security type, collateral, conversion terms, dilution, or financing conditions are provided in the source summary. Utility Dive also noted that experts remain divided over how soon fusion technology could be commercialized.