In mid-March, The Guardian's Robin McKie treated readers to a fascinating article highlighting a concerning problem: the world's supply of helium is being wantonly squandered on party balloons, among other things. And the impact on critical scientific endeavors could be drastic.
"Research facilities probing the structure of matter, medical scanners and other advanced devices that use the gas may soon have to reduce operations or close," McKie wrote.
Unfortunately, fusion energy could also succumb to a helium shortfall. Declining stocks of the inert gas may be a potential limitation for tokamak-style fusion reactors, should that technology ever come to fruition on a meta scale. The superconducting magnet assembly implicit to those reactors requires massive amounts of helium to induce total magnetic confinement of the fusion reaction. There may be up to 30 million years of fusion fuel on Earth, but it wouldn't do a scrap of good if we run out of usable helium in the next century.
But there is good news. Dwindling helium stores wouldn't restrain laser fusion technology, which is the hallmark of Laser Inertial Fusion Energy (LIFE) research currently being conducted at the National Ignition Facility (NIF) of Lawrence Livermore National Laboratory (LLNL) in California.
"For a laser fusion based approach like LIFE, there is no need for helium except in small quantities," Mike Dunne, Director for Laser Fusion Energy at the National Ignition Facility, told RealClearScience. "The little helium it uses -- for various cooling systems -- is in a closed loop, so the only replenishment needed would be from leakages."
Furthermore, according to Dunne, LIFE fusion will actually end up producing substantially more helium than it consumes. Helium-4 is a direct product of the deuterium-tritium reaction, and more will be produced from reactions within the lithium heat transfer fluid. In addition, helium-3 is produced via the decay of tritium and through deuterium-deuterium reactions.
"This helium would certainly be captured for reuse. But, even for quite a large-scale roll-out of LIFE plants, this is still a small amount compared to annual production," Dunne said. So LIFE fusion wouldn't be able to replenish the world's dissipating supply of helium, but it could, however, provide enough of the gas to fill a few party balloons.
For Dunne and the scientists at NIF, the overarching goal is to make fusion power become the clean, almost limitless energy source it's envisioned to be. Thus, they have taken prudent care to plan ahead in order to remedy any possible barriers to a fusion future.
"We have worked to apply this logic to all aspects of the LIFE design to make sure that there are no inherently limiting supply chain issues. This led to the removal of a number of otherwise "traditional" fusion materials, such as beryllium," Dunne said.
Last week, the National Ignition Facility fired an astounding laser shot, delivering a record-breaking 1.875 million joules of ultraviolet energy into a target chamber. It's just another incredible milestone on the path to fusion ignition with energy gain, on target for end of this year.