Scientists at the have achieved a net energy gain through the process of in a that could kick off the development and commercialization of fusion energy in the U.S. The advancement could help us cleanly power our future and everything else, although not anytime soon.

The announced that on December 5, the NIF was able to generate 3.15 megajoules of energy after delivering 2.05 megajoules to a fuel pellet, or target, through the world’s biggest laser. The achievement marks the first known “breakeven” of inertial fusion energy.

The NIF illustrates the process of fusing two atoms into a heavier one , or you can check out a brief video that outlines the pros and cons — including how hard it is to reliably and consistently get more energy out of fusion than you have to put in. The discovery is being lauded as a breakthrough, but the is a long way from harnessing the type of reaction that powers our sun.

And while scientists at the have much to celebrate, there’s much more work to be done if the U.S. is truly planning to open any fusion reactors within the next 50 to 60 years.

That’s more or less the timeframe researchers at the NIF outlined for the deployment of fusion reactors in the U.S., which reflects the 60 years since scientists at the LLNL proposed the use of lasers to induce fusion in the 1960s.

Kimberly Budil, the director of the LNLL, says it’ll take less time to go from this breakthrough to feasible fusion power plants; she claims we could have fusion reactors running before 2072, but it will take “concerted effort and investment” from the federal government and the private sector, as well as from research institutions and even tech startups. The U.S. government has now set aside over $624 million for the fusion energy program under the National Defense Authorization Act, so failure won’t be for a total lack of funding.

But a major criticism of inertial fusion energy (IFE) is that it’s inefficient: the — again, the largest in the world at around three football fields long — required 300 megajoules of energy to drive 2.05 megajoules through a fuel pellet and in the end generate 3.15 megajoules of energy. That’s hardly efficient, but the scientists behind the discovery say the NIF wasn’t designed with overall energy efficiency in mind. Moreover, the facility is still using equipment from the 1980s and 1990s.

The NIF was tasked with proving that fusion energy is achievable. But it’s going to take a lot of work and a lot of people across many institutions to turn commercial fusion energy from a theoretical possibility into a reality. Still, if IFE and lasers and fuel pellets turn out to be what finally wean us off fossil-fuels, then 2072 can’t come soon enough.