Fusion for the future of clean energy
Nuclear fusion is the coveted future technology that powers numerous elements of tech in science fiction, from Back To The Future to Star Trek. What is it and what changes could it hold for our future, should we manage to harness it for ourselves?
Burn Baby Burn
Stars spend eons in perpetual states of combustion, hurtling through the vacuum of space, fueled by nothing more than the elements at their heart. The most important of those elements are hydrogen and helium, the first two to appear on the periodic table. Hydrogen, made of a single electron orbiting a lone proton, is the most abundant and lightest element in the universe. Helium, in its most common form, consists of two electrons orbiting a pair of protons and neutrons and is hydrogen’s neighbor on the periodic table. Back in 1920, astrophysicist Arthur Eddington proposed that stars gained their incredible stamina from the fusion of hydrogen into helium. In 1952, scientists managed to recreate the effects in a lab. Since then, many trials and failures have arisen through the process of trying to develop a functional nuclear fusion reactor.
One of the primary limiting factors in creating a nuclear fusion reactor is containment. Fusion reactions are incredibly powerful and, as scientists have often found out, frequently explosive. There are several approaches to generating nuclear fusion. One of them, inertial confinement fusion, involves heating and compressing fuel while aiming it at a metal pellet containing hydrogen isotopes. The trick with the inertial confinement method is the confinement bit. It’s not unusual for the target pellet to explode before it reaches stable fusion temperatures.
Another technique, antimatter-initialized fusion, is very similar to the concept used to power ships in Star Trek. Antimatter-matter reactions are used to generate bursts of fusion energy as the particles annihilate one another. While the power output of these reactions is substantial, the cost of creating antimatter in any reasonable quantity is expensive, and storing it is extremely difficult. The most colloquially recognizable form of nuclear fusion is the thermonuclear variety. While scientists have managed to execute thermonuclear fusion in high-powered explosives, no method of controlled thermonuclear fusion has ever been attained.
Do It Yourself Energy
The simplest method of generating nuclear fusion is through inertial electrostatic confinement. In this method, plasma is controlled using an electric field, directing the matter inward to heat and compress it to the point of fusion. The generators used to produce such conditions are appropriately called fusors. Skilled amateurs can create these machines at home in their garage, making the race to a nuclear fusion breakthrough anyone’s game. Bona fide scientists and basement physicists alike are hoping to be the first to generate a stable source of fusion, and the competition has led to some wild and wonderful methods.
Arindam Banerjee, an associate professor at Lehigh University, has found an unusual way of studying Rayleigh-Taylor instability, which occurs between materials of differing densities under extreme conditions. To simulate the consistency of the plasma state of the pellets used in inertial confinement setups, he has turned to mayonnaise for help. According to Banerjee, mayo has a similar consistency to the pre-fusion plasma he is trying to study. Being much easier to contain and maintain, mayonnaise is serving as a stand-in for his lab tests to determine the fluid dynamic properties of the plasma and work out the setbacks standing in the way of stable fusion.
A second breakthrough that is more beautiful than it is bizarre is a tabletop device that has managed to maintain a nuclear fusion state for five microseconds. The Z-pinch, which is the first small-scale nuclear fusion device ever created, contains and pressurizes plasma using strong magnetic fields. It’s far from perfect, but the device’s accomplishment of stabilizing plasma for 16 microseconds and generating fusion for a third of that time is an exceptional proof of concept that small-scale fusion is indeed possible.
Nuclear fusion generates immense amounts of carbon-free energy. If a self-sustaining generator model can be developed, not only would we be able to leave fossil fuels in the dust, but we could begin looking at space travel in a completely new light.