A tokamak reactor lined with tungsten has led to a significant advancement in the field of fusion research. The French Atomic Energy Commission (CEA) used this donut-shaped reactor to inject 1.15 gigajoules of energy and maintain a hot hydrogen plasma for six minutes, setting a new record. The US-based Princeton Plasma Physics Laboratory (PPPL) verified the accomplishment.
The Sun’s energy source, nuclear fusion, has great potential as a clean, endless energy source. In contrast to nuclear fission, it produces no hazardous radioactive waste. Furthermore, fusion processes are controllable, offering a dependable, carbon-free energy source.
Tokamak conditions that are similar to those of the Sun are crucial to the fusion process. At a temperature of 50 million degrees Celsius, hydrogen isotopes are heated to create plasma, which is the fourth state of matter. The trick is to keep this plasma stable for long stretches of time (shots) and produce more energy than is required to make it.
Scientists believe using tungsten as the lining material in tokamaks can be a game-changer. Previous reactors achieving longer shots relied on graphite lining, but this material isn’t suitable for larger reactors as it traps fuel in the walls. While tungsten doesn’t have this issue, it’s trickier to work with as even tiny amounts can cool down the plasma rapidly.
“It’s like the difference between trying to catch your pet cat and wrestling a wild lion,” said Luis Delgado-Aparicio, lead scientist at PPPL, highlighting the challenge tungsten presents.
Special tools are needed to handle this demanding material. A specialized X-ray diagnostic tool developed by DECTRIS helps researchers measure plasma properties like core temperature. PPPL researchers further enhanced this tool by allowing each pixel to measure energy levels independently, providing a more detailed picture of the reaction conditions within WEST.
This enhanced tool confirmed the record-breaking achievement: the WEST reactor sustained a plasma with 15% more energy and double the density compared to previous attempts – both crucial factors for generating usable amounts of energy from fusion.
This achievement marks a significant step towards making clean, limitless fusion energy a reality.