The Department of Energy has announced the first ever fusion reaction to generate more energy than used to start the reaction.
Gennady Schvets is an expert on fusion and plasma physics at Cornell University who will lead Cornell’s Laboratory of Plasma Studies starting next year. Schvets says the achievement is significant, but that its shortcomings point to areas ripe for improvement.
“The enormity of this result is that it was obtained via the so-called ‘indirect drive’: laser energy is converted to x-rays, and the x-rays are coupled into the fuel. One of the avenues for improvement is the so-called ‘direct drive,’ where the laser energy goes straight into the target.
“However, here’s a word of caution: these lasers are not very efficient. Their wall-plug efficiency is low and laser designers will have to work hard to improve.
“Currently, fuel compression and ignition happen in a single process. This prevents modularity. It is better to separate compression and ignition, and to separately improve each one. My group is working on a modular approach to target ignition: using multiple laser beams to create a tiny spark inside the compressed fuel.”