(Reuters) - Helion Energy, a fusion energy tech startup, on Friday said it raised $500 million to build a net positive electrical generator, one that creates more power than it uses. The latest round values the company at $3 billion. Helion said $1.7 billion in follow on investments were committed if it can prove its technology works, which would be a major step toward making fusion technology a practical solution for generating power while emitting no carbon. Fusion is the process that fires the sun as the nuclei of two atoms fuse under extreme heat. It creates enormous amounts of energy. Helion’s newest prototype named Polaris will add a so-called regenerative energy technology to its fusion technology already developed to generate electricity, said Helion founder and CEO David Kirtley. The target date for demonstration is 2024. The company broke ground in Everett, Washington in July to build the generator which will be the size of two shipping containers and create enough electricity to power 40,000 homes, said Kirtley. If it works, the $1.7 billion follow-on investments will be used to develop a commercial system, he said. “There’s a real future for fusion to be part of this climate change and clean energy discussion,” said Kirtley, adding that other fusion energy companies were also pushing the timeline forward. He said there were over 40 private fusion companies today. Fusion has advantages over fission as the fuel is derived from water, not radioactive uranium or plutonium and doesn’t generate long-term radioactive waste. Sam Altman, a well-known investor and artificial intelligence researcher in Silicon Valley who led the round, said the long-term goal of Helion is not just to create clean energy but electricity that costs just one cent a kilowatt hour. “I hope we have the best idea, but what I really care about is that someone gets fusion built and globally deployed as quickly as possible,” said Altman. Reporting By Jane Lanhee Lee; Editing by David Gregorio