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 is making a big bet on a power source that hasn’t yet been used successfully anywhere in the world: nuclear fusion. The tech company said on Monday that it will buy power from a planned nuclear fusion plant in Virginia developed by Commonwealth Fusion Systems,

The tech giant is betting that Commonwealth Fusion Systems could start producing fusion power next decade.