In a first-of-its-kind agreement, Google will purchase electricity from a nuclear fusion power plant. But the technology remains years from commercial scale.

Google and CFS aren’t alone in their ambitions. Microsoft inked a deal in 2023 to purchase electricity from a nuclear fusion generator being developed by Helion Energy, which is supposed to be ready by 2028. Around $8 billion from primarily private investors has flowed into fusion startups in recent years, the Washington Post reported last week.

The deal comes even though Commonwealth Fusion Systems has yet to demonstrate that its future power plant can generate power reliably or economically.