Fusion reactors like China’s Experimental Advanced Superconducting Tokamak (EAST) could be the solution to humanity’s energy woes. By harnessing the fusion power of the sun, scientists hope we can generate clean, abundant energy on Earth, but progress over the decades has been slow. Chinese state media has reported that EAST has taken a big step toward making fusion power a reality by keeping plasma at 120 million degrees Celsius for 101 seconds. That’s a new world record, but EAST still doesn’t produce usable power.
EAST isn’t the only fusion reactor with that shortcoming. Tokamak-style reactors have been around for years, but they all consume more power than they produce. The reported temperature of the latest EAST experiment is more than six times hotter than the core of the sun because we don’t have the advantage of the star’s gravity. Therefore, we need more heat. As you can imagine, it takes a huge amount of energy to heat hydrogen until it becomes a 100 million-degree plasma cloud, and then you need even more power to run the super-powerful magnets that keep it contained in the toroidal reactor chamber (above).
Scientists regard 100 million C as the minimum for superheated hydrogen to fuse into helium at a rate high enough to generate power. 101 seconds is still a far cry from continuous energy generation, but this is a big step in the right direction. During EAST’s experiments in 2018, the team reached 100 degrees Celsius for just ten seconds. Last year, South Korea’s KSTAR reactor managed the same temperature for 20 seconds.
Even if the EAST team cracks the code and begins generating power, this piece of hardware has its limits. The stated goal for EAST is to create 100-million-degree plasma and contain it for more than 1,000 seconds (around 17 minutes). Most researchers believe we’re still decades away from a sustainable form of fusion, but it’s possible reactors could begin generating small amounts of net power in the coming years. The enormous ITER fusion reactor could be online as soon as 2025, and the team believes it could be ten times more efficient than existing systems.
Even if EAST or another project succeeds in generating power, that doesn’t necessarily mean cheap, limitless energy is a reality. It currently takes 300 scientists and engineers to run EAST, and it only operates in short bursts. Fusion power won’t be cheap until it works without constant coaxing from hundreds of researchers.