Researchers achieve breakthrough, inch closer to igniting nuclear fusion reaction
Researchers at the Lawrence Livermore National Laboratory's National Ignition Facility (NIF) in California successfully achieved a breakthrough that inches humankind closer to sustainable power generation by nuclear fusion last week. The scientists achieved 70% ignition. "After many years at 3% of ignition, this is super exciting," said Dr. Mark Herrmann, the head of the laboratory's fusion program. Here are more details.
Lasers set off fusion, generated 10 quadrillion watts of power
NIF researchers successfully focused laser light from 192 different sources onto a tiny sphere holding hydrogen isotopes, deuterium, and tritium housed inside a tiny gold capsule. In a 20-nanosecond burst, the lasers produced a hot spot that vaporized the gold and produced X-rays, causing the sphere to implode and generate power, 10 quadrillion watts of it, but just for 100 trillionths of a second.
Generated energy almost 10% of Earth's received solar energy
The New York Times reported that the sun shines 170 quadrillion watts on the Earth. "This is about 10% of that," Dr. Herrmann said. The fusion emanated this colossal amount of energy from a spot approximately as wide as one human hair. Notably, fusion powers celestial bodies, too. It forces small atomic nuclei to combine into larger ones, releasing large amounts of energy.
NIF is first to generate more energy than fusion consumed
Fusion is challenging to achieve on Earth because of the heat and pressure required to fuse nuclei. Nonetheless, it continues to attract scientific and commercial interest due to its potential to generate energy with little environmental impact. In fact, even the NIF event reportedly produced much more energy than the $3.5 billion facilities ever managed.
What's ignition and why is getting to 70% significant?
NIF researchers were able to reach a whopping 70% ignition with the experiment, a breakthrough for nuclear fusion research. For the unversed, 100% ignition is the energy threshold at which a fusion reaction becomes self-sustaining since energy released by one fusion is sufficient to set off another fusion. NIF's experiment released 1.35 megajoules (MJ) of the 1.9MJ required for ignition.
Controlling fusion is critical to ensuring safe operation
Blindly cranking up the laser's output isn't the way forward, though. Uncontrolled fusion creates nuclear weapons. One would need to produce these fusions at a rate of approximately 10 per second to collect energy from the neutrons produced in the reaction. Meanwhile, Science reports that all the other approaches to nuclear fusion disappointingly continue to consume more energy than they generate.
The breakthrough is 'a whole new regime': Dr. Herrmann
The progress comes just in time. The NIF's funding body, the National Nuclear Security Administration, was leaning in favor of using the facility's lasers for simulating the workings of nuclear weapons instead. Dr. Herrmann said, "This (70% ignition) gives us a lot more encouragement that we can go significantly farther". "This is a whole new regime", he added.
