Nuclear fusion could provide for all of our energy needs without creating the deadly nuclear waste that nuclear fission plants produce. It is a noble goal, but one that has eluded scientists for decades. A German machine may be the next step toward the solution.
How would you like to power the world forever using little more than salt water? The idea may sound crazy, but that is what scientists have been working toward for years in the field of nuclear physics. They call it nuclear fusion, and it distinguishes itself from nuclear fission in that it can produce more energy and doesn’t create radioactive byproducts that researchers have a hard time containing.
Nuclear fusion has not been harnessed, however, and it requires materials that are notoriously hard to acquire. Currently, research points to the need for powerful magnetic fields to contain the reaction of nuclear fusion. The difficulty in sustaining such a field has hampered researchers since the 1950s. At the Wendelstein 7-X (W 7-X) stellerator in Germany, that will change.
Harnessing Nuclear Fusion: the Power of the Sun
Nuclear fusion powers our Sun. Harnessing the reaction for power requires containment of superheated balls of plasma. The running theory on how to hold the plasma in place suggests the use of electromagnetic fields. Only recently have researchers found success.
The W 7-X is what is known as a stellarator, which is a technical design first explored in the 1950s. These machines were prohibitively hard to make and utilize, so they gave way to a doughnut-shaped machine called a tokamak.
The tokamak seemed to be the best way to harness nuclear fusion. Yet, recent advances in computing power and plasma knowledge made the stellarator a viable option once again.
The main difference between a stellarator and a tokamak is that the tokamak makes a 2d magnetic field and requires an electric current, while the stellarator creates a twisting 3d field without the need for an internal current. As a result, stellarators are far more stable than tokamaks.
Start it up
Last year, Germany switched on the W 7-X, and it successfully contained an intensely hot blob of helium plasma. However, there were questions about whether or not the magnetic field generator was working as intended. Thankfully, these issues were recently answered. Not only does the generator work as planned, but it has an impressive error rate of only 1 in 100,000.Germany switched on the W 7-X, and it successfully contained an intensely hot blob of helium plasma.Click To Tweet
The team tested the field by applying an electron beam to the magnetic field lines produced by the machine. The fields became visible when the team swept a fluorescent rod through those lines, showing the exact type of magnetic fields intended by the design of the machine.
Researchers are still far from developing a nuclear fusion powered reactor. Nevertheless, the precise magnetic field produced by the W 7-X represent a significant step toward that goal.
The Future of Fission
Despite near-perfect 3d magnetic fields, the W 7-X isn’t meant to produce usable energy. However, it does prove the concept behind containment of superheated plasma necessary for the process.
The next step is to use deuterium to produce fusion reactions within the machine. Yet still, this will not create more energy than what is needed to run the mechanism.
The W-7 faces stiff competition, as tokamaks aren’t out of the running quite yet.
The ITER tokamak reactor in France was also able to trap plasma long enough for fusion to occur, putting it neck and neck with the W-7.
With countries across the world placing emphasis on renewable energies, nuclear fusion could forever answer tomorrow’s energy problems. Whether it will be the stellarator or the tokamak, or a totally new design, everyone benefits from new revolutions in energy technology.