We need to talk about hydrogen safety
In the excitement about its potential to help decarbonise energy, we must pay attention to the details around handling hydrogen safely.
Hydrogen is the most abundant element in the universe, but there’s a really good reason it doesn’t naturally occur on Earth: The conditions on our planet are not naturally tolerant of hydrogen. There’s a clue! Hydrogen on Earth is found as a compound, such as H2O, but pure hydrogen does not survive naturally.
I am urging everyone to remember that in this dash for hydrogen as the fuel of the future, there cannot be shortcuts. There can be no quick and dirty hydrogen energy projects. If that happens, people are going to get hurt.
Turn your mind to the Hindenburg airship disaster of 1937. It came about because people were focused on one outcome – the ability to carry many people through the air across huge distances in the massive zeppelin. The excitement around that meant they didn’t take proper account of the other potential: explosion.
That’s the issue that I feel very strongly is a risk here. Sure, we’re almost a century on and we’ve learnt a lot more about hydrogen, and have become a lot more focused on safety. But there is so much talk on the positive outcomes – using hydrogen as a green vector for energy – that there’s a danger that insufficient attention is being paid to the risks.
I’m on a bit of a mission to keep reminding people that hydrogen is dangerous and difficult to handle, and as we make plans for more people to come into contact with it in one way or another, we have to ensure that the safety protocols are even more rigorous than they have been to date.
For example, we’re looking at people taking fuel-cell cars and refuelling them with hydrogen themselves. As individuals we’re pretty smart, but as a general populace we’re dumb. Humans do dumb things. So from an ABB point of view, I think about how our safety protocols for hydrogen have been operating for many decades in manufacturing and production facilities. That’s when we’re working with highly trained people who are also observing their own company’s safety protocols.
You start to see why we need to create even higher safety standards for hydrogen in general-use facilities. We need to make hydrogen safe for everyone – they’re not going to understand it as we do, and that’s as it should be. It’s the job of everyone working in the hydrogen industry to look after the general population once they start tapping into hydrogen for energy, whether that’s car fuel or in our natural gas network.
To promote more focus and deeper conversations around the risks, ABB has published an excellent hydrogen safety whitepaper. It outlines the four key safety concerns, download it today.
We are used to dealing with flammable products, but they have a relatively high ignition point. Hydrogen has very low ignition, so just the friction of the gas running over a surface itself can ignite it. If it’s under pressure and then there’s a leak in a pipe, and it goes through that leak at pressure, as it goes through the hole, it builds up friction. That friction creates temperature, temperature ignites the hydrogen gas. Boom! We have to remember, this is not about the usual protocols for well-known sources of ignition, where we have no lighters, no matches, no radios, no telephones and so on. Hydrogen ignites so much more easily, so the protocols have to be much more rigorous, and much broader.
Burns with an invisible flame
You may have a fracture because the pipes have been worn down because of their exposure to hydrogen (more on that in a moment). Strangely, a high-pressure leak might not be too bad, because there are ways of detecting those, because they’re audible. But a low-pressure leak through a fracture or an incorrect flange can ignite itself – perhaps through friction, or a bit of sun hitting that metal or another low-level emission source. It burns at low pressure, so it doesn’t suck back into the tank. It burns away merrily and you won’t see it, can’t smell it, can’t hear it, but you walk past it and suddenly your arms are on fire. Or you park your forklift next to it and suddenly it’s up in flames. Hydrogen’s invisible flame is a very high risk indeed.
Highly flammable over a wide concentration range
Hydrogen is not like diesel, where you’ve got to have a specific density and a specific temperature for it to be a problem. Hydrogen will go bang at very low levels of concentration. Massive electrolyzers which will be used to manufacture hydrogen, running on energy from high-power rectifiers. These rectifiers are housed together inside a building to protect them from the elements. Think about it: a huge lump of power from the rectifiers, going into this great big piece of kit, the electrolyzer, and the production of hydrogen. All in an enclosed space. What could possibly go wrong? If you get a leak in that place, you won’t be able to see it because it’s invisible. If it’s a low-pressure leak, it won’t be detected by sonic leak detectors. So a low-pressure leak, in a closed space – this is where the Hindenburg scenario comes in. The hydrogen escapes and builds up silently and invisibly to a certain level of density and – boom – you end up with the roof in the next state.
Can be absorbed into metals
This is the issue with hydrogen that touches all of the above. You only need low energy to ignite it, a very wide level of concentration can create the explosion or fire, and it burns with an invisible flame. All of those potential problems can result from the fact that the metal you’re putting hydrogen through is in fact being embrittled by the hydrogen going through it. Because hydrogen is such a small molecule, it can dissociate into hydrogen ions at elevated temperatures, and be absorbed by surrounding metals. This is a big problem for pipeline operators to solve as the industry discussed putting up to 10% injected hydrogen into LNG networks, using existing pipelines. This works below certain temperature tolerances, but we’re in Australia, with huge temperature fluctuations, and bushfires across the country, including where there are natural gas pipelines. You start to see the potential for big problems .
Apart from all that, hydrogen is easy!
ABB has a lot of experience in helping people safely manage the production, transport, use and storage of hydrogen for a very long time. We know a lot about its physical properties. We know what makes it go bang. We know what its uses are. But we’ve been doing it within a very controlled environment, with experts.
Now we’re moving to the energy industry equivalent of the gold rush – everyone wants to get on the hydrogen bandwagon. If we’re going to use it as widely as is hoped, thousands and thousands of gigatons of hydrogen will be produced and transported every year. I’m saying, whoa, slow down, and be safe.
Come and visit us at the APPEA Conference and Exhibition in Brisbane from Tuesday 17 May through to Thursday 19 May, 2022.