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Comment by Robotbeat | Hacker News Reader

What bothers me in articles like this is that no one mentions that ammonia is not produced with natural gas. It’s produced with HYDROGEN.

The cheapest source of hydrogen is usually steam reforming of natural gas. (But this wasn’t the case until about 1950 when steam reforming became cheap and widespread. Before that, cheap hydroelectricity-produced green hydrogen was common for nitrogen fertilizer production.)

Not mentioning this means that the average person who reads the news (including the typical politician and HN reader) has the mistaken notion that fossil fuels are essential for making fertilizer.

My 2cents: Two consequences (which kind of go in opposite directions) of this are:

1) You really think we need to push hydrogen cars right now when we’re not even producing a significant amount of green hydrogen for fertilizer? Unlike the electric grid (which is 40% clean already in the US), almost no hydrogen for ammonia is made with clean electricity.

2) This should provide impetus for locally produced green hydrogen efforts as food security, insulation from fossil fuel price swings. (Blue hydrogen doesn’t have that advantage since it’s still fossil fuel based and is worse in other ways.)

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>the mistaken notion that fossil fuels are essential for making fertilizer

I think the correct statement is that fossil fuels are the cheapest way of making fertilizer, and that any other (known) way is currently much more expensive. Therefore raising the price of fossil fuels does raise the price of fertilizer. This is pretty incontrovertible.

No, we use hydrogen to make ammonia. That hydrogen is grey hydrogen from fossil fuels usually, but the actual Haber process does not use any hydrocarbons. Using hydrogen to make ammonia is therefore not a new process. It literally IS the process we use today.

An analogy would be an article on hydrogen fuel cell cars that never once used the word “hydrogen” in it.

I'm new to this so asking earnestly, but:

>That hydrogen is grey hydrogen from fossil fuels usually, but the actual Haber process does not use any hydrocarbons. Using hydrogen to make ammonia is therefore not a new process. It literally IS the process we use today.

It seems like this grey hydrogen still ultimately comes from fossil fuels. It might be further up the chain, so to speak, but it's still dependant on them. No? So doesn't the statement that raising fossil fuel prices raise fertilizer prices true then?

Yes, true in the narrow sense, but it’s misleading, I think, or at least it’s avoiding a really good opportunity to educate people about the role of hydrogen in our industrial processes.

I don’t think it’s irrelevant minutiae. By not mentioning hydrogen but mentioning by natural gas, you reinforce the mistaken impression people have that the process we use to make fertilizers requires fossil fuels in particular. It actually uses hydrogen, which historically was, technically can be (and is today on a modest scale), and in the future likely will be made using electricity.

It also avoids context that the Hydrogen Economy is something we have today, but it’s almost all fossil fuel reliant. So a hydrogen car or hydrogen heating or whatever is not intrinsically fossil-free, not even close.

And ammonia is actually a really good use of hydrogen as the actual process itself uses hydrogen, so unlike for heating, where a Joule of hydrogen gives you the same as a Joule of natural gas for heat, a Joule of hydrogen gives you more ammonia than a Joule of natural gas would. AND you can avoid the capital cost of the on-site steam reforming.

Anyway, I just think such articles should say something like “Fertilizer production, in which nitrogen from the atmosphere is fixed by combining it with hydrogen, is the largest industrial use of hydrogen—almost all of which is today produced on-site from fossil fuels like natural gas.”

Or even just “nitrogen fertilizer, which uses hydrogen usually made from natural gas…”

The idea that hydrogen is largely green but fertilizer intrinsically requires hydrocarbons are two really common misconceptions that we could easily fix by just mentioning “hydrogen” in these news articles.

In the case of the plant pictured in the article, the hydrogen is produced on site from methane. So, at least in that case, from the factory perspective, it is a methane in, ammonia + CO2 out. [1] I don't know how common it is for factories to do both processes at the same site, but that would explain why the article frames it that way.

But beyond that, I think the parent comment is just saying that the price of the hydrogen plays a big role in the availability and price of fertilizer. Even with the current increases in price, it is not profitable to manufacture ammonia using green hydrogen at current market prices.

[1] https://www.cffertilisers.co.uk/about-us/how-our-fertiliser-...

From the factory perspective, 1 Joule of hydrogen produces more ammonia than 1 Joule of natural gas AND you get to avoid the steam reforming equipment, saving capital & maintenance cost.

And in Europe, at the moment natural gas prices are so high that green hydrogen is now competitive. BUT that’s beside the point.

I really think you are trying to obfuscate the issue here.

We "usually" make the hydrogen from fossil fuels because this is by far the cheapest way to make it, so if we raise the price of fossil fuels, the fertilizer becomes more expensive. And man, you are twisting and turning in order to obscure this fact.

No, I’m not. Again, by not mentioning that ammonia is made from hydrogen (and not mentioning that ammonia is by far the largest use of hydrogen today and also that almost all hydrogen is made with fossil fuels now but not historically), we are obfuscating multiple things. It seems implied that ammonia based fertilizers actually need hydrocarbons in particular (which isn’t true historically, technically, or in the future, BUT you’ll have many Degrowther types argue we have to use fossil fuels for fertilizer) AND it makes it easy to exaggerate the benefit of hydrogen cars (or the “hydrogen economy”) because it becomes unclear that hydrogen is actually by far made from fossil fuels. It’s not a simple consequence.

(Finally, green hydrogen is currently competitive with grey and blue hydrogen in Europe due to high gas prices at the moment, but that’s totally beside the point.)

https://think.ing.com/articles/hold-1of4-high-gas-prices-tri...

Thanks for your comments. Until today, I was under the mistaken impression that fertilizers required hydrocarbons.

We usually make electricity from coal, because its so cheap... as long as you ignore the pollution and death that it causes.

An insistence on how "cheap" it is to make fertilizer from natural gas, without taking into accoint fugitive methan emmisions, the fossil fuel used for the heat, and the CO2 released as an intrinsic part of the process seems the more obvious, at at this point preictable and boring, attempt to distort reality.

Turns out we make twice as much electricity in the US from natural gas than from coal, and we use about as much nuclear power as we do coal for electricity (and nuclear is equal to about all the hydro, wind, solar, and geothermal we use). This is another thing I think people aren’t aware has changed. ~80% of our electricity in the US is made without coal.

(But globally is another story, and this doesn’t really affect your overall point.)

The reduction in coal in the US and several other countries has been mostly driven by people internalising those externalities, often via a carbon price mechanism, but also by banning or limiting specific types of pollution.

It would probably still be "cheaper" without those. Luckily sanity has, somewhat, prevailed and costs that were being imposed on others in the country were also considered.

> Therefore raising the price of fossil fuels does raise the price of fertilizer.

Yes, but how much does this impact the total retail cost of the food we eat? Would it be a difference of 2%, or a difference of 200%?

That's the only number I (as someone who eats food) care about.

Good question. 3kg of hydrogen makes about 17kg of ammonia. One bushel of corn requires about 0.8 pounds of ammonia.

A bushel of corn weighs about 56 pounds and a pound of corn has about 1566 kilocalories.

Grey hydrogen is about $2/kg (more in Europe right now, about $5/kg not counting CO2 tax), and green hydrogen is about $3-6/kg, depending on your electricity costs.

So one kg of hydrogen produces about 1,367,000 kilocalories, or about 683 days’ worth if you ate just 2000kilocalories of field corn per day. :) A price difference of $1-4/kg for hydrogen means less than 1¢/day… of course that’s only if you eat just corn at the bottom of the food chain and use efficient agricultural practices… also, everyone gets a cut on the way…

This is truly one of the more interesting HN comments I've read recently. I'm actually surprised how little H goes into a bushel of corn. This really makes the potential future energy tech even more exciting.

Keep in mind that’s for state of the art practices. In much of the world, productivity of food production is an order of magnitude less (corn is pretty much the most productive modern staple crop), and a bushel of corn produces about 6.7 pounds of beef, which is an order of magnitude fewer Calories than the corn you started with. Plus there is food wastage. With inefficient processes, the cost could be two orders of magnitude higher!

So the increase in actual food prices could be far greater than just one cent per day.

>Yes, but how much does this impact the total retail cost of the food we eat? Would it be a difference of 2%, or a difference of 200%?

As with everything else in the food supply the difference will be felt at the bottom first.

Whole Foods stuff has plenty of margin (obviously "plenty" is relative, this is a thin margin industry) to absorb a small increase. Those bottom dollar Walmart tomatoes that have to get here from Argentina and need to be sold for bottom dollar? Yeah there's no space in the margin, those have to go up in price proportional to inputs.

I was reading the other day about these guys:

https://www.nitricity.co/

"Renewable on-site nitrogen fertilizer production"

Maybe some people here could find their process interesting.

Yes, this is interesting because it's not the haber process!

Very exciting stuff, and drastically changing the transportation costs gives them a good niche so they can build a foothold without having to go toe-to-toe with the existing natural gas derived Haber process, which has the benefit of already being highly optimized.

Electrolytic hydrogen production scales poorly. Cost aside, the additional electricity required to replace methane-derived hydrogen is completely infeasible for the foreseeable future.

Just because we can produce almost any chemistry with electricity does not imply that we have remotely enough spare power generation capacity to make it feasible. Too many proposals for green industrial chemistry implicitly assume that we have several terawatts of green power generation just lying around, which is manifestly not the case nor are we likely to have that kind of extra capacity on any timeframe that matters.

Power grids regularly go negative couldn't there be money made from chemical production on hot and windy days

For some unknown reason, transmission/distribution pricing is often fixed, even though peak users are directly culpable for the costs of upgrades.

I'm not certain that is actually correct. The biggest steel maker here in Sweden is in early stages of replacing coal with hydrogen in their new production chains they are building, based on wind power. The really good part is that it is a consumption of electricity that is pretty resilient against varying production volumes, which make it pretty ideal for renewables.

The same logic could very well work with fertilizer.

Of course it’s not correct. I have no idea why people speak so confidently about electrolysis not being “scalable” when, in fact, that used to be pretty much the primary way of making hydrogen for ammonia.

Also, the US used to double electricity generation every decade. If something needs a bit more electricity, there’s no “scaling” argument why we can’t just produce more electricity. It costs money, of course, but there’s no part of it that isn’t “scalable.”

The amount of electricity required to generate an equivalent amount of hydrogen for ammonia production by electrolysis is 1.5-2 PWh annually. That significantly exceeds all wind power generation globally, even assuming we could dedicate it entirely to making ammonia, which of course we can't because we need to keep the lights on.

I also don't think you understand what it means to run an industrial plant at that scale or the logistics (pipelines and such) implied, particularly when the power source is so diffuse. You keep using the words "scalability" but it isn't clear you understand what that actually means in this context.

If you are interested in this stuff, perhaps you should study chemical engineering. The feasibility issues will be more intuitive.

2 PWh is not really a challenge other than scaling it up. We have many orders of magnitude more wind and solar energy that the world needs. Water won't run out either, especially when you realize that salt water can be used for this process.

I don't think you are understanding the differences in scale. Ammonia is produced in truly massive quantities, it is one of the highest volume industrial chemicals produced. It is transported around the world in pipelines. The amount of hydrogen used to make steel is a rounding error by comparison.

Making hydrogen via electrolysis requires 50 MWh per ton. Manufacturing ammonia requires tens of millions of tons of hydrogen every year.

Right, about 40 megatons of hydrogen to produce all the nitrogen fertilizer. About 270GW average electrical power (67% HHV efficient hydrogen electrolysis, not counting liquefaction or compression).

BUT ammonia is a global commodity that can be and is distributed all over the world, so that means you can produce it wherever clean energy is cheapest. Chile has excellent wind AND excellent solar (best in the world), meaning you can operate electrolysis at higher capacity factor, and it has sea ports. So there are plans for big green ammonia projects being built there. https://renewablesnow.com/news/engie-enaex-plan-green-hydrog...

But it can also just provide food security by being a local source of fertilizer that is independent of global logistical constraints or fluctuations in availability of natural gas.

It’s also potentially an alternative mechanism for hydrogen storage. Some ships already run on ammonia, and you can run tractors (etc) on it as well without the extreme challenges in storage that compressed or liquid hydrogen have (its somewhere between LNG and propane when it comes to storage difficulty). However, it’s probably not a great consumer fuel due to toxicity.

Does it scale poorly for any reason other than current availability of electricity?

The growth of PV has been pretty close to exponential since ‘92, with the current (nameplate) capacity estimated to be just short of 1 terawatt and a doubling time of 2.2 years, so I think we will have a few terawatts on a relevant timescale.

It actually scales extremely well. Based on DoE studies I’ve read, Hydrogen electrolysis systems that are larger tend to have lower specific capital costs and usually operate at higher efficiency than smaller plants. We also used to double electricity production every decade before demand for electricity plateaued. Sometimes people just say things on the Internet that are wrong.

Turn off bitcoin does that provide enough power so the world doesn't starve?

More specifically, Bitcoin consumes about 10GW average. To make all nitrogen fertilizer with electrolytes hydrogen would require about 270GW average. It’s nowhere close.

Ok, but most fertilizer production uses natural gas to supply the hydrogen and fossil fuels of one sort or another to bring everything up to temperature. So, why should this article go out and say, 'well theoretically we could obtain hydrogen some other way...'.

Haber-Bosch is slightly exothermic. The turbomachinery for doing the pressure-swing product condensing in the loop might have too high losses to get by without external power supply, though.

Electricity is a pretty great way to power turbomachinery.

Well, the reaction needs a compressor, followed by a pipe reactor loaded with catalyst, followed by an expander, followed by an ammonia droplet seperator/condenser. That result is then fed back to the input along with more educts, and side-products are siphoned off slowly to prevent their accumulation.

The expander is there because you increase the percentage of ammonia that will condense by both lowering the temperature and lowering the pressure, which an ideal expander is very good at.

You'd prefer if that expander can power the compressor, with this setup being essentially a gas turbine with exhaust rebreathing and the combustion chamber replaced with a giant tube reactor filled with catalyst.

It’s not “theoretical.” It’s literally how we used to make hydrogen for ammonia.

And all I’m asking is to mention this uses hydrogen so people aren’t confused.

3) It is fine with a slightly uneven production of hydrogen as it only means you have to build up a buffer of it for sustained usage. This means it is ideal for hydrogen produced by wind and solar power.

Many argue that we need to end our dependence on chemical fertilizers and farm in a biodynamic way.

https://youtu.be/1BH0NkN6zHs

And many people are dumb. The Haber process is one of the greatest inventions in the history of mankind. A majority of people alive today can directly trace their very existence to the food production yield increases from artificial fertilizer. It's estimated that 50% of the nitrogen in the average human comes from the Haber process.

Now I'm not going to try to pretend there are absolutely no downsides. Runoff from fields is a huge issue. But when you advocate for large scale returns to "natural" farming, you're taking a position that leads directly to ecofacism and genocide though famine. Or at least a radical restructuring of the global economy where much greater sections of land and the labor force would be required to be farmers.

I think you will find if you watch the video I linked that Jean Martin Fortier is anything but dumb.

In order to not downplay how much of an issue artificial fertilizer is in term of runoff, practically every fresh water lake in western countries have become poisoned. The whole Baltic Sea is turning into dead zone where even bacteria have a hard time surviving, and in many countries that have a coast, both humans and animals can't be in the water during long parts of the year for the risk of getting poisoned. If you have one ocean area where you test nuclear bombs, and the other where you have "normal" amount of runoff from artificial fertilizer, the nuclear bomb site will be healthier and have more diverse ecological environment.

We might not want to ban the stuff, but we need to start demanding that farming is a closed loop in term of artificial fertilizers.

That honestly says more about our misplaced paranoia on nuclear waste and the environment than it does anything else.

If you dive in the coast of the Baltic Sea from may and for the rest of the year, this is what you will likely see: (https://www.azotelibrary.com/en/image/Omr%C3%A5de-med-syrebr...). Similar for most lakes, except the color is then only black and brown.

Miles and miles of grey, black and green mass of death.

Not if we automate small acreage farms.

Your take is very opinionated but doesn’t seem to include any helpful solutions.

Habitat and environment is more important than profit margin because we are a super apex predator and rely on the planet’s eco system to survive…not just thrive.

Genocide through famine occurred in India when the British exported Indian cotton and tobacco and turning fields of grain into cash crops. It was not ‘eco fascism’ but colonialism that caused it.

Fertilizer run off, deadzones and poisoning of our water tables is just one side effect of Big Ag.

Long supply chains and cold supply chains and an animal based diet has caused more famine (not to mention food waste amongst the wealthy) than ecological focus on Ag. Not to mention an overpopulated planet that has long since crossed carrying capacity. Perhaps temper your hot takes with relevant inputs?

Yes good to see you Lalitha! Totally agree of course.

Hey Hey!! We should catch up!!

Yes! Sent you a ping.

> But when you advocate for large scale returns to "natural" farming, you're taking a position that leads directly to ecofacism and genocide though famine. Or at least a radical restructuring of the global economy where much greater sections of land and the labor force would be required to be farmers.

Actually I am designing an open source farming robot focused on regenerative agriculture so that everyone can move to automated regenerative agriculture in an affordable way. Honestly I really think you are talking a big game without really knowing what you are saying.

very cool, i am going to check this out. we are converting our own yard to small scale farm / aquaponic system, and automating it is something i would love to do!

Great! More details on our robot here: https://community.twistedfields.com/t/a-closer-look-at-acorn...

We need green hydrogen for steel production as well, if we want to get that carbon footprint down.

Indeed. All new iron ore reduction plants built in the last few decades in the US have used syngas (a mixture of hydrogen and CO) made with natural gas for reducing the iron ore to iron metal, NOT coal/coke. These plants use about 50% hydrogen already, that amount can be increased modestly at existing plants with almost no modifications, and with significant modifications that can handle over 90% hydrogen. “Midrex” is one proprietary version of this Direct Reduced Iron (DRI) process.

I think few people (unless they’re actually in the industry) are aware that all new iron ore plants in the US use natural gas, NOT coal.

But what fraction of total production comes from those, and how do we increase that ratio?

Not mentioning this means that the average person who reads the news (including the typical politician and HN reader) has the mistaken notion that fossil fuels are essential for making fertilizer.

But it's true - currently this is how fertilizer is made. Maybe there will be a large scale source of hydrogen in the future, but currently it comes from fossil fuels.

You don't need to worry about politicians getting incorrect knowledge from the news, they get that knowledge directly from industry.

> Maybe there will be a large scale source of hydrogen in the future, but currently it comes from fossil fuels.

No, see, this is again the misunderstanding I’m talking about. Ammonia is made with hydrogen, period. The “large scale source of hydrogen” exists today. It is steam reforming of natural gas, and before that it was electrolysis of water.

This is the misunderstanding I'm talking about: "steam reforming of natural gas", is the same as "fossil fuels". If you're going to rely on some future development where the hydrogen doesn't come from fossil fuels, then you can also declare that gasoline and diesel are not fossil fuels since non-fossil fuel sources exist for both.

I mean, there’s lots of green hydrogen production in California right now. Clean electric synthesis of hydrocarbons is most certainly possible but a lot more expensive, complex, and inefficient, and I’m not aware of any place you can just buy it, unlike green hydrogen in places like California. Hydrogen electrolysis used to be the dominant method of making ammonia hydrogen. Hydrogen electrolysis is simple enough there’s a Kiwi Co tutorial on how to do it with household items: https://www.kiwico.com/diy/stem/quick-easy-experiments/split...

Hydrogen allows you to skip steps in the typical ammonia plant. Synthesized gasoline is just a huge cost increase, almost an order of magnitude larger than that for clean ammonia.

But we need to keep all our hydro power for green crypto for ElonFlokiDoge token, not squander it on food.

> which is 40% clean already in the US

Can you define that statement a bit more? What do you mean by clean?

If you're going off of the industry terms, that 40% includes natural gas, and is probably mostly natural gas. Which means cracking natural gas into hydrogen isn't any more or less polluting.

Nuclear, wind, hydro, and geothermal (and maybe some biomass) produce about 40% of the electricity in the US. And yeah, if we’re just using grid electricity at the current electricity mix to make hydrogen, we’re not any better off than using steam reforming. That’s a very valid point. But it’s relatively straightforward to decarbonize the grid. Just build more solar, wind, geothermal, and nuclear and keep what we’ve already got running. Retire coal ASAP.

I have an odd, and possibly naive, question. Why wouldn't it be easier ( and cheaper ) to produce hydrogen from water rather than natural gas?

Hydrogen is bound in both compounds - you need to expand energy to extract it.

As in our oxidizing atmosphere natural gas is a source of (chemical) energy, you can burn it to provide the energy needed to extract the hydrogen. This is the steam reforming reaction.

Since water is not a source of energy, you need to add (expensive) electrical energy in order to extract the hydrogen. This is the electrolysis reaction.

It's significantly more expensive to make it from water than methane.

The cost of industrial chemistry is largely the amount of energy required to produce a ton of chemical. There are different ways to make any chemical all of which have different cost structures depending on the application.

Making hydrogen from water is extremely electricity intensive, around 50 MWh per ton. Even aluminum production from ore, which is famously electricity intensive, only requires a small fraction of the energy input that hydrogen requires when produced this way.

Making hydrogen from methane has a more expensive feedstock (methane versus water) but requires vastly less energy which makes it much cheaper overall. I would guess that methane feedstock also requires a less expensive plant per ton of production capacity, which would also lower costs.

We need to build the freaking nuclear plants and make hydrogen as an energy storage when not in peak.

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