22 September 2021. Hydrogen | 3D Printing
Trying to assess the role of hydrogen in the energy transition; 3D printed houses
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#1: Trying to assess the role of hydrogen in the energy transition
Hydrogen is going to be a critical fuel in the post-carbon transition—especially carbon-neutral or ‘green’ hydrogen, rather than ‘blue’ or ‘grey’ hydrogen—so it’s good to see that Michael Liebreich has updated his Clean Hydrogen ‘ladder’ to a fourth version. Kudos to him for making the diagram available under a creative commons licence.
(Michael Liebreich, CC)
Liebreich observes that there is a view out there that hydrogen will do everything, but obviously that’s not the case:
The problem is, just like a Swiss Army Knife, you won't use hydrogen for everything you could theoretically do with it. Clean hydrogen will have to win its way into the economy, use case by use case. It could do so on its merits, or it could do so because of supportive policy (including carbon prices). But it will have to do so in competition with every other clean technology that could solve the same problem. And that is where the dreams of the hydrogen economy hit reality: in almost all use cases there is a good reason why hydrogen is not currently used - because other solutions are cheaper, simpler, safer or more convenient.
As well as the Swiss Army knife version, there’s a set of ladders for each sector, colour coded from green through orange to red, according to how valuable/competitive green hydrogen is. The most competitive applications are those that replace existing blue or grey hydrogen.
He breaks these different applications into whether hydrogen is unavoidable, or whether other power sources might provide alternatives—whether biofuels or battery/storage. There’s a ladder for each sector, but the overall summary looks like this:
(Michael Liebreich, CC)
In short, the critical sectors look like being chemicals and processes:
Current uses of hydrogen - principally for fertiliser, oil refining and petrochemicals production - currently accounts for around 2% of global CO2 emissions. Clean hydrogen has to win here, as there is no alternative.
Clean hydrogen offers a very promising way of decarbonising steel, but its not 100% sure, because there are alternatives like molten oxide electrolysis that could out-compete it. As clean hydrogen gets cheaper, and if cheap CO2 becomes available via Direct Air Capture (unlikely) or as a byproduct of biogas production (more likely), we could start to see it used to make a range of chemical feedstocks.
He’s clearly done more analysis of all of this than I have, and having the whole map laid out like this is a real service. All the same there are a couple of sectors here where I have had to research energy alternatives.
In aviation, for example, I’d agree that short-haul planes are likely to be battery powered; but for medium-haul Airbus has pivoted towards hydrogen because it’s not persuaded that batteries will be dense enough to do the longer distances.
And while biogas or biofuels might work as an individual technology solution for the sectors flagged here, there might not be enough of it in total—meaning biofuels produced without impacting food production—to fulfil the demand here. (The UK Climate Commission did some work on how you’d end up prioritising the biofuel supply to maximise carbon reduction impacts and transport didn’t come high on the list, see p112 onwards).
In fact it would be useful to see a set of biofuels ladders to look at where biofuel application is also ‘unavoidable’.
It’s also worth noting that the publication of Liebreich’s latest ladder seems to have sparked a noisy set of green hydrogen-sceptical articles at CleanTechnica, (this, for example) which I haven’t yet had time to explore properly.
But it’s worth noting Michael Barnard’s view that overall global hydrogen demand will fall, basically because current demand from petroleum refineries and fertiliser production (which together are two-thirds of global demand) will shrink drastically. On the other hand, he sees significant demand growth in the steel sector.
But I’m sceptical of CleanTechnica’s rather exact forecasting. This is an area of massive technological, infrastructural, and user uncertainty, and the whole future energy system is a complex system with a lot of emergent parts. A little less confidence—and a bit more options thinking—might be more useful.
3D printing, or incremental manufacturing, has been the future almost as long as I have been doing futures work. I’m fairly sure that I included a slide about it in a drivers’ deck in 2003 or 2004. And I worked in 2012 with the late John Urry and Thomas Birtchnell, and my colleague Chloe Cook, on a set of scenarios about the impact of 3D printing on the freight sector.
Those scenarios looked out to 2030, but so far the early projections that many homes would have a 3D printer sitting alongside their paper printer haven’t happened.
But what has happened is that 3D printing has become a high end technology, making specific parts for high value goods—aero engine parts, for instance, or top end racing cycles. Or making a ratchet wrench to complete a job on the International Space Station.
(Photo: ICON)
So perhaps we shouldn’t be surprised to see a report of 3D printing being applied to build a street in Texas. (In Austin, of course).
To be fair, it’s not a very long street (more a close, with only four houses), and there’s not much detail about the cost in the article (although other online sources, including the video below, quote prices of $400-450,000, or around the median price for Austin). But some of the detail is interesting.
First, the time it took: 5-7 days per house, which is a lot faster than conventional construction methods.
And second, the performance of the materials:
3D printing robotics layer cement onto striated surfaces. According to (the construction company) ICON, this system creates a tough, highly weather-resistant design. The 3D printing technology “provides safer, more resilient homes that are designed to withstand fire, flood, wind, and other natural disasters better than conventionally built homes and that can be built in a matter of weeks,” the company said in a statement.
j2t#172
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