alt Hacker NewsRight. It also makes it sound like they’re not using the Haber Bosch process… but then:
> Electrolyzers are located on-site. They use wind energy to split water into hydrogen and oxygen gas.
> Additionally, nitrogen gas is directly harnessed from the atmosphere using an air-separation unit.
> Hydrogen and nitrogen are combined under pressure, resulting in carbon-free ammonia fertilizer.
That sounds a lot like the Haber Bosch process to me. So they’re just saying, rather than divert excess generation to a battery, you could instead build a micro H-B plant on site to produce ammonia.
I doubt this makes any sense in the grand scheme of things as you achieve major efficiencies at scale for chemical plants. Makes more sense to just electrify existing ammonia plants and ensure they use renewable electricity sources.
The green chemistry industry is full of penny-wise pound-foolish concepts like this and it drives me absolutely nuts.
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There's a lot of places in the world where there's room for wind but the grid can't transport it to a user. In that case consuming it locally would make sense, and especially fertilizer is a very energy heavy product.
So it might be easier to pipe the ammonia to wherever it's needed? When it's in ammonia form the energy is essentially stored for a long time.
What if the Ammonia is used locally? Potentially, in that Minnesota farm.
It eliminates the need to connect the turbine to the grid.
>That sounds a lot like the Haber Bosch process to me.
Well, kinda. But Haber-Bosch uses an iron catalyst. This is cheap, but it requires very high temperatures and pressures. There has been some recent work on ruthenium catalysts (particularly a Japanese company Tsubame BHB) which are more expensive, but allow the reaction to proceed under milder conditions. A particular goal is to have smaller facilities which can then be colocated with power generation. So you are exchanging a higher fixed cost for hopefully lower variable costs. I don't know if that's actually what they're doing here, though.
It is literally the Haber-Bosch process, without question. The school actually calls it that in their own paper, https://cbsi-asabe.org/wp-content/uploads/2024/06/Harvesting..., because that is what it is.
I assume what confused the article is that ammonia plants often use natural gas, but that's purely as a convenient energy source and a source of hydrogen, so they cover both angles. But that isn't remotely a necessity.
Not to mention ammonia isn't the friendliest of chemicals and doesn't exactly beg for decentralized logistics.
I think, projects like these grew out of dunkelflaute moral panic regarding renewable energy. Meanwhile grid battery storage has becomes cheap enough to completely obliterate this concern.
And quite frankly, fertilizer needs in agriculture should be addressed by ecological means anyway. If we want to lower the impact of climate change, we need to get out of this "just throw more energy at it" technology mindset.
What I find funny is people that build machines that extract carbon from the atmosphere. None of the articles about it ever mention the energy cost in running the machine or howinell it could be scaled up to make a measurable difference.
But trees, for example, are 50% carbon, extracted from the atmosphere. And they're solar powered! And look nice.
From doing a bit of digging into this myself after hearing it being promoted on the radio, I both agree and disagree. Working through the $/acre for on-site produced ammonia using locally-generated electricity (I forget if I was looking at PV or Wind, doesn’t matter) the payback period was surprisingly quick, like 2 or 3 years. One of the big reasons is that you don’t actually need a very big system; you only need on-farm ammonia a few days a year but you have all year long to harvest and store enough for those few days.