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Comment by kurthr | Hacker News Reader

This is the well known Haber-Bosch process, "Between 75 and 90% of this ammonia goes toward making fertilizer, and about 50% of the world’s food production relies on ammonia fertilizer."

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It’s worth noting that the Haber process doesn’t require methane, methane is used as a source of hydrogen because it’s cheap and easy to use. Any source of hydrogen could work, but most of them are more energy intensive and thus more expensive or inefficient than just using methane. If you wanted to use nuclear or renewables, you just dedicate your energy production to electrolysis or whatever.

Edit to add: also worth noting that electrolysis currently amounts to about 5% of hydrogen production. You basically can’t remove fossil fuels from the food supply without lots of alternate energy input, so this is not a short term fix short of spooling up all kinds of nuclear reactors.

I’m not saying it shouldn’t be done, and maybe if we need to be dependent on fossil fuels for any one thing then we should prioritize food supply rather than literally burning them (or worse, venting them to the atmosphere as is often done with methane), just trying to set the right expectations for people who might be learning all this for the first time.

You can still use methane as your hydrogen source for ammonia production if you do CO2 capture and storage when you produce the hydrogen. This is often called blue hydrogen, as opposed to green hydrogen from electrolysis and gray hydrogen from methane witgout CO2 capture and storage.

Most of the oil and gas companies are partly betting the farm on H2 from CH4 with CO2 capture and storage as a major source of energy in the coming transition, and thus a major source of profits for the next 30-40 years.

Many people regard CO2 capture and storage as an attempt by the oil and gas industry to be able to green-wash what they current do without actually having to change anything.

I don't really care if Exxon is the most valuable company in the world because they discover a way to capture CO2 out of the air and pump it into old wells.

Almost everyone agrees (finally!) global warming is an existential threat for humankind. If you start bringing up other random environmental concerns you lose supporters quickly.

I agree it's easy to spin it that way. But I do also think it's true that we can scale up CO2 capture and storage one or two orders of magnitude more quickly than we can scale up renewables. And we will need that capability.

Just take solar power in Europe as an example. It is projected that we need to install 300 GW of solar in the next three years. But the rate of new installations has been basically flat at about 20-25 GW per year for the past 10 years.

Or take wind - we are going to install 21 GW this year, but next year that number will decrease due to constraints in permits and transmission grid capacity. To meet climate targets we need to add at least 30 GW per year.

At this point it's simple math that renewables cannot be deployed quickly enough.

You can also produce methane from renewable biomass (biogas), this is mature tech and in many places used as a transport or CHP fuel.

Define short term, if we really want I`m quite sure we can dramatically increase pv power generation in a few years. There are vast swathes of little used space in sunny environments. But you do need to invest proper amounts of money, just like we do for developing new fossil fuel sites. The investment for a new LNG field and liquefaction plant is in the order of USD 30-50B. We need to redirect such investments to PV and hydrolysis.

"cheap" in the same sense as free parking in cities, as in "someone else pays the cost". And the "someone else" in these cases is actually us a.k.a not cheap, but rather pointlessly wasteful.

This process is the reason Malthus was proven wrong back in the day. We wouldn't be able to support 8 billion people without it.

Given that

> Malthus observed that an increase in a nation's food production improved the well-being of the population, but the improvement was temporary because it led to population growth, which in turn restored the original per capita production level

What proved him wrong (or at least currently looks that way) was declining fertility levels, not increased food production.

Malthus was wrong because he assumed that people would always want to have a lot of kids.

Back in his days people would have a lot of kids because they kept dying, but he didn't realize that. Nobody did at the time.

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