As digital beings, our appetite for consuming energy is ever increasing. With nuclear energy constantly on the rise we are setting ourselves up for increased dangers from radiation and putting further strain and strain on our planet. But there is hope on the horizon: the inverse of nuclear fission, nuclear fusion. You may be asking what else is new? Enter the Z Machine! It just might be the answer to revolutionizing the way we create energy forever.
A quick recap on nuclear fusion: we dream of harnessing this process which occurs naturally in stars, including our Sun. Due to extremely high temperatures and immense pressure, a star fuses two hydrogen atoms into a heavier helium element. Thanks to Einstein’s E=mc₂ equation, two small masses release a massive amount of energy. The beauty of fusion, unlike nuclear fission, is that it does not produce nuclear waste or radiation. This makes fusion a completely clean energy. Is there a catch? Well, we do however, have to deal with the produced high energy neutrons which are released during fusion.
The Z Machine located in New Mexico has one primary function: it creates the conditions found in a star to recreate fusion. Up until now, the ITER project, the International Thermonuclear Experimental Reactor, is the main candidate in pursuit of the shared dream of fusion. 35 countries are part of this project, and all are hoping to create star like conditions here on Earth.
What makes the Z Machine so unique? Instead of creating a cloud of Hydrogen gas, it works “by firing huge amounts of electricity (more than 20 lightning bolts of energy) from about 26 million amps through a tiny fuel-filled cylinder about the size of a thimble.” This surge will create an unimaginably massive magnetic field. The field strength impacts the cylinder so suddenly and strongly it causes the hydrogen atoms inside it to fuse, creating the heavier helium nuclei and high energy neutrons. For a spectacular image visit Science Mag.
Physicists are now planning to expand the Z Machine to make the “bangs” even bigger by using precious fuel. Instead of only using deuterium, which releases limited amounts of energy due to its one neutron nucleus, the team are introducing tritium, which has two. Over the next five years the ratio of deuterium to tritium will be increased to 50-50, resulting in a production of four times the amount of energy. Another advantage of the Z Machine is that it has no containing walls, which can absorb up to 70% of the fuel. The Z Machine’s container is the magnetic field itself.
The downside to all of this is that tritium is a radioactive element. The free high energy neutrons produced by the fusion process make the steel parts of the apparatus slightly radioactive. Humidity in the air is vicious as it forms tritiated water, an extremely biologically hazardous element. Despite these potential dangers, the team will go forward using tritium. The extra neutrons it creates will shed light on the nature of the deepest, densest plasma created during fusion. Don’t forget one major aspect: all of these states of fusion only last for instants. A sustainable fusion reaction is still very much in the future…or so current thinking suggests.
Wishing you an energetically fused weekend.