It's a huge step toward the energy holy grail. //

Plasma is volatile, and particles that escape the sun-hot plasma stream react with the materials that enclose the tokamak. This stops the plasma fusion reaction because the temperature falls out of the effective zone, but more importantly in Maslow’s hierarchy, it’s also wildly dangerous for the reactor itself and everything around it.

The PPPL team found that while boriding—literally, coating with boron—helps to keep plasma in the right reaction state, the existing method is too dangerous. Nuclear scientists use diborane gas, which is made of boron and explosively flammable hydrogen. To use it, these scientists must stop their tokamaks completely, introduce the gas, then leave again because of the flammability. At PPPL, they thought there must be a better way.

To make the process just as effective, but far safer, the PPPL team tested the use of both pure boron and boron nitride powders. The powders are inert, meaning they don’t react with anything or catch fire. The researchers applied the powders by injecting them into the tokamak while it was running, which is another method improvement over diborane gas. Once inside, the powder worked the same way the gas did: It kept the temperature in the high performance zone, which keeps the plasma more stable and prevents scraping the sides of the tokamak’s chamber.