The world is currently struggling to generate enough electricity, but there is a real possibility that we will need to phase out fossil fuels over the next few decades. And what is left then? Wind? Solar? Maybe we could skip the middlemen and make our own solar power through fusion, but the technology to make it happen is still evolving. However, researchers at Lawrence Livermore National Laboratory (LLNL) say they have taken an important step in the production of fusion energy. For the first time, a fusion reaction generated more power than the fuel absorbed. This puts humanity on the verge of creating usable energy by harnessing the power of the sun.
The team conducted this experiment at the National Ignition Facility (NIF) in August, and the results have yet to be peer reviewed. LLNL will be submitting an article soon. News first broke in August, but interest is on the rise as the team prepares to try again. LLNL also spoke more about how he improved the efficiency of the merger in the NIF, which he said by a huge margin. For example, the fuel for the experiment was contained in a new high density carbon (i.e. diamond) target capsule.
The NIF is the size of three football fields and is equipped with 192 high-power lasers. The lasers focus on a small capsule of deuterium and tritium (isotopes of hydrogen). The lasers hit an object called a hohlraum, which converts the laser into x-rays that bombard the fuel and come close to the heat and pressure of a star, but only for a moment. Initial analysis of the August experiment shows that the reaction generated over 10 quadrillion watts of fusion power for 100 trillion seconds. It’s a big achievement, but some of the early success reports confused fuel absorption with ignition, and that’s not where we are.
While this is an important step forward, there is still no ignition – the point at which a sustained fusion reaction can generate net energy. This experiment achieved a record power output of 1.3 megajoules, the NIF used a total of 1.9 megajoules. This does not detract from the importance of this achievement. “Experimental access to thermonuclear combustion in the laboratory is the culmination of decades of scientific and technological work spanning nearly 50 years,” said Thomas Mason, director of the Los Alamos National Laboratory. Although we cannot yet generate energy from fusion, the effectiveness of these techniques is improving rapidly. In 2013, the FNI was handle only 14 kilojoules, and now it’s two orders of magnitude higher.
It will take time for the scientific community to dissect this latest work, but the LLNL team reports improvements in laser focus, hohlraum efficiency, and target crafting that have boosted energy production by more than eight times compared to the experiments a few months earlier, and 25 times the NIF record for 2018. LLNL also plans to repeat the experiment to confirm its results. He started setting up the experience after the initial success, so it shouldn’t be much longer before the team is ready to relaunch the NIF.