Livermore, California - A nuclear fusion experiment that produced more energy than it consumed for the first time is a first that could upend the entire field of energy production, the US Department of Energy (DOE) said on Tuesday.

"This is an announcement that has been decades in the making," the department tweeted.

"On December 5, 2022, a team from DOE's [Lawrence Livermore National Laboratory] made history by achieving fusion ignition. This breakthrough will change the future of clean power and America’s national defense forever."

The breakthrough marks a milestone on the way to developing a new source of energy that could possibly one day generate electricity in huge quantities in a sustainable and safe manner. It was first reported by the Financial Times on Monday, and the DOE's confirmation brought a wave of celebrations from the science community and policymakers.

Researchers at the Lawrence Livermore National Laboratory succeeding in basically getting out more than they put in, which has been described as the "holy grail" of clean energy.

Blasting hydrogen plasma with a high-powered laser led to a reaction that produced 3.15 megajoules of energy for the price of 2.05.

This, of course, is just the beginning of a long road that will involve scaling and many efficiency tweaks before fusion ignition can become a reliable commercial energy source, as was pointed out by Mark Herrmann, program director for weapon physics and design, at a press conference on Tuesday.

"There are many, many steps that would have to be made in order to get to inertial fusion as an energy source," he said, before also pointing out – in less optimistic news – that the experiment has implications for modernizing the US' "nuclear deterrent."

The jarring suggestion that this advance in nuclear fusion would quickly be weaponized was also present in the DOE's tweet, with its reference to "America’s national defense."