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You didn’t even read what you quoted!

The Haber Process for making nitrogen fertilizer uses HYDROGEN as the feedstock for making ammonia, NOT methane! Natural gas steam reforming is just the cheapest source of hydrogen (usually), but before about 1950, we used electricity (usually from cheap renewables like hydro) to make hydrogen for ammonia. Easy peasy with wind and solar!



Yeah I just read a couple other articles and you're right. I was about to delete my post actually, when I saw you responded to it.

It does seem like most places don't currently have the infrastructure in place to do proper green hydrogen though, since only 0.1 percent of hydrogen produced as of Jan 2021 could be considered green hydrogen.[1]

So I don't think it's quite as 'easy peasy' as you're suggesting, probably a lot of money has to be invested and infrastructure has to be built to support it, but sure, I'm all for doing that.

[1]: https://ohvec.org/the-myth-of-green-hydrogen/


Like most climate change things, it is relatively easy-peasy from a technical standpoint (as the other commenter noted, this is how we used to do it in the olden days).

It's just hard to build a thriving business around that when your competitor can dump CO2 into the atmosphere for free and leave someone else to pick up the tab.

Once the competitor starts using his profits to buy politicians and fake scientists it gets really complicated, but making lots of fertilizer with renewable energy is not only technically easy, it's actually one of the things that will help the uptake of renewable energy globally.


The largest project I know of for this so far is 100MW of hydrogen electrolyzers in Spain:

https://www.iberdrola.com/about-us/lines-business/flagship-p...

We will be seeing a lot more of these in the future. By making fertilizer out of air, water, and sun, a lot of places could gain more independence too.


There is a reason we don't often use electrolysis for hydrogen production -- it scales poorly and is expensive. Scaling that up several orders of magnitude is not a realistic option.

This is true of most electrolytic industrial chemistry, for example the hydroxides used in many carbon capture schemes. What works for the small-scale needs of today for industrial chemistry are not intrinsically scalable. In software terms, industrial chemistry is not "embarrassingly parallel" for reasons that are not immediately obvious to the layman, so scaling is hard.


That’s simply not true. Electrolysis scales JUST fine (the process for making aluminum is much the same although occurs at often higher temperature, and we used to use electrolysis for ammonia’s hydrogen). We just don’t do it because steam reforming is usually cheaper. Simple as that.


Hydrogen use 4x the amount of electricity per ton as aluminum, and that assumes you are not recycling aluminum. It is orders of magnitude less if it is recycled, which most aluminum production is. You'll need to come up with a less specious example than aluminum if you want to be credible.

We also produce significantly more hydrogen than aluminum in any case.


I’m not sure why you consider that “specious.” Aluminum requires less electricity per ton because hydrogen is the least dense element. Per mole, hydrogen uses less electricity than aluminum. :)

And we don’t produce massively more hydrogen than aluminum. Global primary aluminum production is ~64 million tonnes per year. Hydrogen for ammonia production (which is the majority of hydrogen I think) is about 40 million tonnes per year out of about 75 million tonnes total pure hydrogen. Certainly the same order of magnitude.

But again, this is missing the point. Before around 1950 (when steam reforming became widely available), hydrogen for ammonia fertilizer was produced commonly by electrolysis, often using cheap hydroelectric power. It was done at massive scale and only stopped because steam reforming happened to be cheaper.

And what is your point, here, by saying we make more aluminum than hydrogen? “We can’t credibly do things that are any different, even if just different by degree, than what we happen to do right now.”?




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