In early March, the National Ignition Facility fired up its lasers and emitted a 1 million joule pulse of highly concentrated light. The demonstration came ahead of schedule for the over-budget facility, which cost $3.5 billion—almost 3 times its original budget of $1.2 billion—to complete. On Tuesday, the Department of Energy gave its blessing for the facility to go ahead with regular operations, the San Francisco Chronicle reported.

The new facility, which is part of the Lawrence Livermore National Laboratory in California, has three planned missions: It will provide a way to nondestructively monitor the health of existing nuclear weapons stockpiles, and will be used to simulate early conditions in the Universe. But it’s real glamour comes from plans to trigger controlled nuclear fusion, in which the lasers would heat a small core of hydrogen atoms until they fuse together and released more energy than the laser put in.

Controlled nuclear fusion has been a goal for physicists since the discovery of lasers, but is also the butt of decades of science jokes, since its proponents have been declaring it ‘just a decade away’ for decades.

The San Francisco Chronicle reported on Tuesday that current Secretary of Energy Steven Chu told an audience in 2006: “I’m going to skip (discussing) fusion because it will probably skip the 21st century.”

If it does emerge this century, it may happen simultaneously in Europe: a similar French laser facility, called Laser Mégajoule, is slated to begin operations in 2010, according to a recent Nature story.