Rising worries for helium shortages
But first to an important resource that’s normally invisible, unless it’s filling a balloon, that is - that’s right, it’s helium. But squeaky voices and party balloons aside, helium is actually a crucial part of modern life - from running MRI machines to making the semiconductor chips in your smartphone, helium is vital, which is why scientists get nervous about the fact that its supply can fluctuate, and one day, we could literally run out...Eva Higginbotham spoke with one such scientist, Sophia Hayes, from Washington University in St Louis...
Sophia - Oh, you know, there are so many properties of helium that make it a very special element. Of course, many of us know that it's lighter than air. It can lift objects. And that's why we have helium balloons and weather balloons and the like, but it's also unreactive. And what that means to those of us who are chemists, is it doesn't change the composition of things when it touches another atom or molecule. If you think about oxygen around us, that turns iron into rust or steel into rust, what happens with helium is it just doesn't react with anything else. But then the really important property is that it's the coldest substance that one can buy on earth. And we scientists use that. And like you said, it's used in MRI machines.
Eva - So it doesn't like making friends with other molecules. And it's also very cold. Where do we actually get it from?
Sophia - Helium comes along when we mine natural gas and bring it up from underneath the earth. So there's a bit of helium that's stuck there fortunately for us. And so when we bring up that natural gas, we can separate the helium from that other methane.
Eva - And how much helium is down there - sort of as a percentage with the methane that we're bringing up?
Sophia - You know, in a good source, tt's only about a percent, maybe sometimes as high as 5%, but many, many natural gas sources have much less.
Eva - And is that why the supply can go up and down?
Sophia - Ah, yeah, that is a really complicated question and I'm so glad you said a just-in-case model at the start of the program versus just-in-time. Helium has a very hard time being stored. And so comes up with this natural gas mining, but occasionally there are geopolitical situations with Qatar or Algeria, and that will shut down an entire source. The US Source has a large inventory because we have a rock formation where we store it, and so we have a unique capability here, but even occasionally we have shutdowns for maintenance. So the whole market goes out of order when one of these supply sources goes down.
Eva - And so what happens when we have a low supply to all of those MRI machines?
Sophia - The MRI machines are less at risk because many of them are in a closed cycle, kind of like the radiator on your car, but other kinds of applications, the semiconductor industry, and even those of us who don't have those closed cycle systems, then they're all at risk. So semiconductor lines have to be shut down. And in the case of those MRI-like magnets, that puts them at risk because they need to be maintained in that cold state for their entire lifetime. So it puts them at risk because they might warm.
Eva - And do we have any replacements for helium when there is a low supply?
Sophia - Sadly there is nothing like it, it is a special substance, again with no other alternative that we can find. And so while we might come up with an alternative for one application or another, there's really nothing like it, it's quite special.
Eva - And if we get it from underground, do we know sort of how much is left underground? Will more continue to be created? Where does it come from?
Sophia - It comes from the decay of elements, such as uranium and thorium. And so we have some estimates of how much uranium is on the planet, but what that means is that we're making helium one atom at a time and it's a very slow process. You see, you know, the earth is estimated to be about 4 billion years old. And so luckily a lot of these crust formations have trapped helium underground, which means it's there for us to pull out. But that 4 billion years has given us a lot of time to produce that helium, one at a time. So estimates say something on the order of a 200-year supply.
Eva - And that doesn't seem like that long actually considering it so important! Seeing as it's lighter than air, does that mean that the helium we get just goes up into space?
Sophia - Yes, exactly right. And that's a problem because it doesn't stay here on Earth. As soon as we've let it go, it's truly gone forever.
Eva - Does that mean that we could go get some from space if it sort of all ends up there?
Sophia - I wish! Wouldn't that be terrific? It would be such a terrific solution, but of course out in outer space, it's just so dilute. And even though there's helium up there, it would be so hard for us to collect an atom at a time again.
Eva - So what should we do? Does this mean that it should be the end of helium balloons to preserve them?
Sophia - That's also complicated. Let's just say those of us who use a lot of helium, we really ought to recycle it in such closed cycle systems. For example, the semiconductor industry, to the best of my knowledge, doesn't recycle the massive amounts of helium that they use. They are also used for rocket propulsion and there is not really a good way to recycle that as well. But those of us with MRI and related strong magnetic equipment, they're called superconducting magnets. If all of us began to recycle, it would certainly be a better way to preserve that resource.