That is, the vast majority of nitrogen-fixation for fertilizers is done using natural gas or other petroleum product: https://en.wikipedia.org/wiki/Ammonia_production
The primary point is that agriculture, as it is currently practiced on a large scale, is extremely dependent on non-renewable resources and the energy in those resources. It's not just natural gas used for nitrogen, it's also things like phosphate mining.
Yes, the amount of calories in the final product largely comes from the sun, but it is the energy in those (currently) petroleum products that unlocks a plant's ability to photosynthesize in the first place.
I was worried about the phosphate thing for a while since, unlike resources like copper and rare earth metals, the used phosphate mostly ends up in the oceans, not conveniently concentrated in landfills. Getting it back out of the oceans is pretty difficult.
But then I looked into it a few years back. It turns out that the absolute amount of phosphate in crustal phosphate rocks is staggeringly huge: about 0.1% of the crust is phosphorus, almost all as phosphate, conventionally measured as P₂O₅, which would thus be 142/62 of that, or about 0.2%. This works out to be on the order of 10¹⁹ kg of phosphate. World phosphate production is 53 million tonnes (https://www.fao.org/3/i6895e/i6895e.pdf), less than 10¹¹ kg, so at current consumption rates we will run out of phosphate in about 10 million years.
Given this, you might wonder why "phosphate reserves" are stated as only a few tens of billions of tonnes! The answer is that currently most phosphate minerals are unprofitable to mine because they can't compete on price with the fairly pure concentrated apatite deposits in the US, Morocco, and China. When those deposits are exhausted (probably sometime in the next few centuries), the price of phosphate will rise, unless we're mining it from the Moon or the asteroids by then. That will make it profitable to extract phosphate from less concentrated resources.
So, while it is technically true that phosphate rock is a "nonrenewable resource", the implication that we will run out before the Pyramids have crumbled into dust is not.
The bigger problem with phosphate mining is phosphogypsum, not energy consumption or running out of phosphate minerals. Detoxifying phosphogypsum is not a difficult chemistry problem, but there is a lot of it and nobody is paying to detoxify it, so it sits in waste dumps. I wouldn't be surprised if we saw a red-mud-style industrial disaster or two with phosphogypsum in the next few decades.
Around 50% of the input is indeed from nitrogen, but it need not be derived from fossil fuels since you could source energy elsewhere and use water electrolysis derived hydrogen in the nitrogen production process. That it is currently more economical to use fossil fuels is a separate issue.
In the same way that bunker fuel powered ships are just "more economical" than transporting goods by sail powered ships.
People throw this term around like making it "less economical" to produce food is some minor detail.
Things being their current level of "economical" is what drives our global economy at the current scale it runs at. We could not have our current lifestyle using sail powered ships to transport goods from China any more than we could maintain anything like our current lifestyle if we had to produce all of our nitrogen fertilizer through electrolysis.
Making food "less economical" means mass starvation.
Robotbeat's calculations seem to show that producing all of the US's nitrogen fertilizer through electrolysis would use something like 5% of US electricity production, which would not be a major obstacle to "maintaining anything like our current lifestyle", and presumably the numbers in other countries are even better, except for the Netherlands.
I don't think there's any point in arguing if you think 5% of electricity (of which, as Robotbeat pointed out is 60% fossil fuel generated) is "not a major obstacle" while we also have to reduce/eliminate fossil fuel use in every sector. It also doesn't touch on the price increase in food production.
Where in the world is all of this extra energy going to come from if you remove fossil fuels from the equation? Robotbeat's analysis there is terrifying to me, rather than reassuring. But you can put works like "just" and "only" as modifiers to whatever you want if it makes it sound more achievable.
Increasing electricity production 5% would not mean mass starvation. China increased electricity production 5% every six months throughout the 02010s. The US did it every year in the 01960s. It's not some kind of impossible obstacle to "maintain[ing] anything like our current lifestyle".
This is the problem with our intuitions about energy, we're so used to abundant, high energy density, relatively cheap energy that we can't even get our heads around not having it.
You quote me but miss the point where I say that this is fine so long as we have unlimited fossil fuels and there are no serious externalities with fossil fuel usage.
Both of these conditions are false, but even your reasoning here is assuming these are true.
If for some non-fossil fuel related reason we had to switch to primarily electrolysis hydrogen production, then yea, we'd be fine. We haven't even come close to really solving just replacing our current energy demands with entirely renewable energy (which, even assuming perfect battery solutions, also requires growing the overall output of our grid by a factor proportional to intermittent power needs), let alone additional energy requirements that start popping up all over the place once you start removing fossil fuels.
This has been a problem that has been well studied and understood for years, but because it leads to the scary conclusion that our current way of life is unsustainable it is brushed off.
China's growth in either solar or wind generation capacity in 02020 was bigger than their growth in coal generation capacity. I haven't seen the 02021 numbers yet but I expect that their coal generation capacity growth in 02021 will turn out to have been actually negative, i.e., not growth but shrinkage, quite aside from the lower-capacity-factor crises resulting from their feud with Australia, their main coal supplier.
Quoting from my notes in Dernocua (http://canonical.org/~kragen/dernocua):
> Specifically, in 02020, the People’s Republic of China installed 71.7 GW of new wind capacity, 48.2 GW of new solar capacity (which was already larger than the rest of the world combined), and 38.4 GW(e) of coal capacity. Assuming typical capacity factors of 40% for wind, 25% for solar, and 60% for coal, that would add up to 23 GW average new coal, 29 GW average new wind, and 12 GW average new solar. (But China’s capacity factors are lower; see below.) New solar installations worldwide double on average every three years, which has slowed down from every two years in the 02010s. ...
> But China is a larger country than Germany. Chinese marketed energy consumption was 28 PWh/year (3.2 TW) in 02010, of which 3.9 PWh/year (440 GW) was electric. In 02019 they produced 7330 TWh electric calculated as (+ 4554 233 148 349 1270 32 405 224 113) rounded to three places. That’s 836 GW. (The 32 TWh of pumped-storage hydro may be double-counted.) In 02019 224 TWh/year (26 GW) was produced from solar and 405 TWh/year (46 GW) from wind, using 204 GW of solar capacity (capacity factor 13%) and 209 GW of wind capacity (capacity factor 22%). Also the 4554 TWh/year from coal (519.5 GW) is on a 1.041 TW basis, so their capacity factor is only 50.0%. Hopefully they’ll start installing their energy plants in more propitious places, like the Gobi, and the capacity factor will go up.
> So probably last year’s new installations of 38.4 GW (coal), 71.7 GW (wind), and 48.2 GW (solar) will produce on average 19.2 GW (coal), 16 GW (wind), and 6.3 GW (solar). The resulting 22 GW (average) of renewable energy added last year amounts to 2.6% of the total current electric energy use of China. If we assume that China’s total energy use has increased by 90% since 02010, just as their electrical energy use did by 02019, it would now be 6.1 TW, and 22 GW is 0.36% of it.
Solar energy (127 PW at Earth's surface) is far more abundant than fossil-fuel energy consumption, which has never reached more than 15 TW, 0.012% of solar energy. Historically the big problem has been that solar energy, though abundant, was expensive to gather; that problem has now been solved, and solar panels are now cheaper in the world market than either fossil fuels or fossil-fuel plants, let alone the sum of the two.
> Both of these conditions are false, but even your reasoning here is assuming these are true.
No, my reasoning is based on evidence that says it is feasible and economical to expand power generation using renewable energy. It is not assuming either "unlimited fossil fuels" or "no serious externalities with fossil fuel usage."
> We haven't even come close to really solving just replacing our current energy demands with entirely renewable energy (which, even assuming perfect battery solutions, also requires growing the overall output of our grid by a factor proportional to intermittent power needs), let alone additional energy requirements that start popping up all over the place once you start removing fossil fuels.
Let's take these one by one.
First, current renewable energy production is about 12% of world total primary energy consumption (https://en.wikipedia.org/wiki/World_energy_supply_and_consum...). More than half of this is hydro, which is, roughly speaking, not growing. The other half is solar and wind, which is growing 14% per year, which puts it on track to replace all of world total primary energy consumption in 02043.
Wind is currently much larger, and already supplies most electricity in countries like Denmark, but solar is growing about 23% per year and has now reached about 1 TW peak, 150 GW average. That means that it is currently supplying about 0.8% of total marketed energy consumption, 1/128. (Since this is all electric, the percentage for electrical energy is higher.)
Of course, when exponential growth is involved, prediction is very difficult, because sooner or later the exponential trend must stop, at which point the trend line diverges from reality by orders of magnitude. Even a small misprediction of the exponential growth rate results in misprediction by an order of magnitude after a few orders of magnitude of growth. https://en.wikipedia.org/wiki/Solar_power#/media/File:PV_cum... shows that the exponential trend was a fairly consistent 36% per year over the last 30 years, so it seems to be slowing down, but it's unlikely to stop anytime soon. I've investigated the fundamentals and can't find any resource limitation or demand limitation that would prevent it.
Solar is currently on track to surpass wind around 02030, so probably we'll move to a majority-renewables energy system before the 02043 you get from extrapolating the overall non-hydro renewables growth rate.
As for the intermittency question, it doesn't affect hydrogen electrolysis (a gasometer full of hydrogen is a perfectly reasonable way to store excess energy for up to a month or two) and to the extent that intermittency is managed at the peripheries of the grid rather than the center, it doesn't require additional transmission or distribution capacity as you say either. Moreover, even needing to double transmission or distribution capacity would not be a civilization-destroying crisis; as I said, PRC has done that three times over the last ten years, and to generation capacity too.
Finally, the additional energy requirements that start popping up are basically only fixing nitrogen into ammonia, smelting steel, and plastics. All three of these are small compared to the use of fossil fuels as fuels.
This is indeed a problem that has been well studied for years, but until five years ago, we didn't know how we could scale up PV production; there was the concern that it might be physically possible but out of our technological reach, like fusion energy. That problem has now been solved, and that is why, for example, Peabody Coal went bankrupt and coal-fired power generation is globally in decline.
Our current way of life is unsustainable in many ways, but needing a lot of energy isn't one of them. We can increase our energy usage by two orders of magnitude before it starts to be a sustainability problem.
-hydrogen is not a primary energy, no accounting for energy needed to produce 1kg of H2 gas -producing ammonia from hydrogen consumes energy -producing corn from ammonia requires more embodied energy than sunlight - other fertilizers, *cides, fuel and construction industrial sized agricultural machinery.
Only measuring the chemical energy in quantity of H2 vs the dietary calories in associated corn produced is incomplete model of fossil fuels required in agricultural production.
If you are saying the urea price spike has occured in a complete isolation, like temporary specific failure of urea manufacturing , maybe its not a problem. If its one of the first noticable effects of an overall fossil fuel shortage, its going to have huge feedback effects invalidating economic models such as slowing renewable growth, making the whole economy less productive.
You might want to put a blank line between your list items so they don't come out as a single paragraph and/or format them with ·, •, or ●.
I think the urea price spike is due to a temporary collapse in natural gas production, which is indeed one of the first overall effects of reduced excess production capacity in natural gas, or shippable natural gas anyway. I don't think an overall fossil fuel shortage would slow renewable growth, though; it increases the returns to renewable generation, and renewables production is one of the sectors of the economy least dependent on fossil fuels.
I think an overall fossil fuel shortage is unlikely because coal reserves are still enormous and interconversion of different kinds of fossil fuels is lossy.
Ammonia is a highly fungible global commodity, and is commonly a means for countries with large natural gas resources to produce an easily transportable value-add product from excess natural gas. None of those countries are going to produce electrolytic ammonia because consuming natural gas is the entire point! If it wasn't being turned into ammonia, much of it would ended being vented to the atmosphere or burned off. While it doesn't look like it in isolation, a lot of industrial chemistry is actually reprocessing and finding value in the waste products of other industrial processes.
The US currently produces ~10% of the global total, but we used to import ammonia like everyone else until a glut of domestic natural gas made it cost-effective to produce our own (again, a way to consume excess natural gas). Ammonia is feedstock for a ton of cost-sensitive industrial chemistry, not just fertilizer, so costs will show up in places people might not expect.
Here's an industry-focused article that talks about growing manufacturing electrolyzer capacity and lists some recent projects for generating hydrogen with renewables:
https://www.pv-magazine-australia.com/2021/12/12/sunday-read...
I feel like inherently hydrogen production via electrolysis is just not that complicated a process: it's a bottle of lyewater with some sheet metal or graphite in it connected to a DC power supply, the sort of thing you could plausibly rig up if stranded on a desert island if you happened across some metal. So I'd think that, although you can surely improve efficiency in lots of ways that increase the cost of the electrolyzer, there's some kind of electrolyzer you can make that has an optimal cost/efficiency tradeoff when you know you're going to run it at a 25% duty cycle. Maybe it isn't cost-competitive with more highly optimized always-on nuclear-powered electrolyzers, but (as the article points out) they aren't cost-competitive with steam methane reforming, either.
It's wonderful to see RMI cited as "major industry analysts" next to BloombergNEF. Nobody deserves that title more.
Chemistry is an exercise in biasing a stochastic process to produce high yields of a desired chemical. This is very sensitive to small changes in the environment e.g. temperature, pressure, pH, concentration, et al. At scale, it is impossible to have a uniform reaction environment as a matter of physics, so the objective is to get as much of the environment as close to the ideal point as possible with clever engineering and then keep the system in equilibrium around that point. This involves finding approximate solutions to vast and fiendishly intractable systems of partial differential equations, that can also be turned into a real physical plant.
If you have variable energy inputs, the system will very likely spend most of its time outside the high-yield sweet spot of its operational parameters. It also takes a long time for these systems to reach equilibrium (often hours or days). Effectively, these processes are binary -- at equilibrium or turned off -- with significant spin up and spin down times with terrible yields.
With base load power, you can have hydrogen electrolysis as part of your continuous chemistry process. A close (but not quite) drop-in for a methane reformation subsystem.
So how is variability (e.g. due to demand) often handled in real systems? They run several plants in parallel and shutdown a fraction of those plants, incurring the startup/shutdown costs. Some industrial chemistry is adequately done batch-y e.g. mining related, but most things asymptotically converge on continuous steady-state processes because there are significant economic benefits in doing so.
Hydrogen electrolysis is probably amenable to batch production without a significant loss of efficiency, though it would incur storage costs you would not have with a continuous plant. The bigger issue is that the downstream processes to which hydrogen is feedstock are unlikely to be amenable to efficient batch production. Because ammonia is produced at such exceptional scales, efficiency matters, and electrolysis is already more expensive than methane reformation.
We are a very long way from mass starvation.
[1] https://www.rts.com/resources/guides/food-waste-america/
That's not a separate issue. That's the WHOLE issue. The first 2 words in the quote were "Modern agriculture". The point is not that there are many types of farming that can be done without using fossil fuels as an input, nor that in the future we couldn't transition away from fossil fuels for fertilizer. The point is that the output of modern agriculture would, at present, completely collapse if the energy input from fossil fuels wasn't available.
I just noticed, before these civs would be geographically separated and isolated, the demise of one, didn´t mean the demise of the other, and the people that had settled and survived, would become nomadic until settling again or something like that.
What will happen when this global civ collapses? Where would the survivors be able to go to, to persist?
Nowhere?
Dark indeed
And in more recent centuries, "collapse" is almost always synonymous with political turmoil/change while the peoples remain in place.
I think that's important too, because we're not seeing so much of a "collapse" of our global civilization, but migrations of peoples across it, and a rise in political turmoil as a second order effect.
Mars! /s, kinda
We have the science and technology to address these issues, the thing that fucks us is our political/economic/religious structures. If we collectively agreed on solving these problems we could, but unity seems to be the scarcest resource of all.
The other side of that coin, though, is that global society has introduced global risks, in terms of the amount of CO2 it is able to put into the atmosphere (which is a shared resource we all rely on), and the ability to create weapons or pathogens of global destruction due to technology.
Also, 50% of the energy does not come from fixed nitrogen. Majority is from the Sun.
Building the necessary renewable energy and ammonia plants and infrastructure is technically trivial in that we needed approximately no innovation as the tech already exists.
The scaled of the problem is immense.
Heck, you can get about halfway there just on the nuclear power plants in the US that have been shut down in the last couple decades!
(Works well with intermittent renewables, too, as hydrogen production can be throttled without much penalty.)
Or the equivalent in new renewables, if that’s your preference.
(And that’s about 10-20 new nuclear reactors, not 40. A fraction of our current nuclear fleet.)
You mean, except in a $Trillion sense. One or two demonstrator plants don't prove anything, except that the advantages are underwhelming, if they exist at all.
How do we globally get there from here? Who is made worse off? Who benefits? How long does it take?
"Exercises for the student" are not always so simple.
How would this input be "several fold less" than the energy output of the system?
Fixed nitrogen, ie ammonia (for instance), is made from gaseous nitrogen and hydrogen. 3kg of hydrogen makes 17kg of ammonia. 200 pounds of ammonia (16kg of hydrogen) will make about 250 bushels of corn. 1 bushel of corn is about 370MJ. 1kg of hydrogen is 142MJ. So 2.3GJ of hydrogen makes 92GJ of corn. That’s about 3%, not 50%.
BTW, the US produces about 17 megatonnes of ammonia per year, or 3 Megatonnes of hydrogen per year. At 60% efficiency, that would require about 22 Gigawatts of average electricity, or less than 5% of average US electricity usage. The US grid is about 40% clean, so that’s still only about 10% of US’a clean electricity usage.
US Ammonia production per year: https://www.eia.gov/naturalgas/weekly/archivenew_ngwu/2021/0...
This was basically my point.
>50% from (FIXED) nitrogen is wrong, though.
Sorry, I wasn't clear. I was saying that 50% of the artificial energy input (i.e. excluding free sunlight to the plants) IS from the nitrogen, rather than farming equipment, transportation, etc.
The history of ammonia production has led to a fossil fuel dependency chain. This article at resilience.org seems to include some good history: https://www.resilience.org/stories/2006-06-11/implications-f...
One of the primary processes involved in the creation of ammonia is the Haber-Bosch process, as outlined on Wikipedia here: https://en.wikipedia.org/wiki/Haber_process
The International Energy Agency provides a good summary of a technology roadmap for migration of ammonia production processes to lower-emission methods: https://www.iea.org/reports/ammonia-technology-roadmap/execu...
And finally - I've no connection with the University of Michigan but I did find this recent article about a research grant for solar-powered, energy-decentralized fertilizer production; I'm not clear on the details of the research yet but it does again re-iterate the nature of the problem and illustrates that there is effort directed towards overcoming fossil fuel dependence in this area: https://news.umich.edu/2m-to-replace-fossil-fuels-with-solar...
The primary reason that Malthus was wrong in his predictions about population growth and food supply isn't because of "science" it's because of fossil fuels.
This wouldn't be an issue if fossil fuels were unlimited in supply and didn't have very severe externalities in their unrestricted usage.
People don't like to talk about what the food supply looks like under a zero emissions scenario with our current nitrogen productions methods.
edit: This comment getting quickly downvoted is objective evidence for my argument that "People don't like to talk about..." There's nothing controversial in this comment. In a world without fossil fuels we very likely would have seen Malthus's predictions come to be, fossil fuels are obviously a limited resource and their usage has extreme externalities.
I get that people are scared, but it's still sad to see a community of otherwise curious people start to break down when they see facts that make them uncomfortable.
I'd have to run the numbers... but offhand I'd guess it just means nitrogen gets 2.5x more expensive. (Call it 2-10x if you want some padding) That doesn't even mean food gets 2.5x more expensive, only that the percentage of costs due to nitrogen go up that much. I think this is such a non-issue.
According to some articles I’ve read targeted towards farmers [1], they are able to compensate by using less fertilizer-dependent crops. So, we can expect small price hikes and major shifts towards using soybeans in place of corn where possible.
[1] example: https://www.agriculture.com/markets/analysis/crops/fertilize...
I, for one, love to talk about zero emission food production.
It's not scary, and in fact it will be somewhat straightforward to replace our nitrogen sources with zero emission production methods.
Electricity can be used to produce ammonia in many ways. The most obvious is electrolysis of water to hydrogen, and then through the Haber process. Large scale production is already being planned, for example by Fertiberia in Spain, who will deploy many MW of electrolyzers soon. Spain's target for electrolyzers is 4GW by 2030! We couldn't even build 4GW of nuclear by 2030, but we will be able to do elecrolyzers and the solar to power them.
There is also a startup (blanking on the name) that creates ammonia on site, off grid, using high voltage in a box. This eliminates the transport cost of nitrogen, which is not insignificant. By focusing on small scale production on site a small startup can break in to a huge commodity market.
I didn't downvote your comment, but your unnecessary pessimism does not accurately reflect the future that we can see already!
See https://richearthinstitute.org for more.
There is a direct causal relationship between energy consumption and economic growth. End the former and you end the latter. And you also kill off a ton of people because the system that enables their lives will falter and starve them to death.
Energy from gravity and radiation are contributing factors to fossil fuel production, even if the hydrocarbons broken down for use are largely photosynthetic in nature/origin, they owe their energy density that makes them a viable fuel source to factors beyond solar. Breaking that down has side effects beyond pure photosynthetic processes.