Agriculture's reliance on fossil fuels (recycle, organic, greenhouse gas, fertilizer)
Please register to participate in our discussions with 2 million other members - it's free and quick! Some forums can only be seen by registered members. After you create your account, you'll be able to customize options and access all our 15,000 new posts/day with fewer ads.
Many years ago I read a book titled The Vegetarian Myth in which one small part has stuck in my memory. It was talking about the Haber process and the 20th century shift towards using it instead of animal manure as a source of some of the nutrients required for fertilizing crops. It's believed that without this process, the population explosion of the last several decades would not have been possible, implying that if the use of this process were eliminated, the world population would have to dramatically shrink.
For those unfamiliar with the process, I will save you the time of looking it up. Essentially, ammonia is made by combining nitrogen from the air and hydrogen from natural gas.
I interpret this situation as being condemned to use fossil fuels (or at least natural gas) until resources literally run out. It's not even a matter of becoming so expensive that we stop drilling, because people will always need to eat. Even if the energy industry were to shift to 100% renewables and plastics and other petroleum-based materials were phased out, I can't see an alternative source of ammonia that is capable of supporting the billions of people that are currently alive.
I'm not going to pretend to understand the Haber process more than what Wikipedia can tell me, but nobody I talk to in person ever seems to even be aware of this aspect of unsustainable use of petroleum. So I'm hoping somebody here can confirm or deny how much this process actually matters. As of my current understanding, we are a slave to it. And my opinion is a bit split. On the one hand, as an aspiring petroleum engineer, I see future job security despite the world turning against fossil fuels. On the other hand, I fear that later generations will see a time when natural gas is becoming much harder to find and acquire which will make crops more expensive and probably result in mass starvation. If I remember correctly, the book I mentioned claimed that by using sustainable, ecological farming (which requires animals), the world could only support about 2 billion people.
I interpret this situation as being condemned to use fossil fuels (or at least natural gas) until resources literally run out.
Hydrogen is the most abundant element in the Universe, there is many sources. One has to remember necessity is the mother of invention, technology marches on. The process of obtaining it from methane would be used because it's likely the most economical way to get it. For starters methane itself can be captured from livestock/manure, sewers and even landfills. They already do this some places and use it as a source of energy. If you were to do this with all livestock this would actually solve two issues because methane is a very powerful greenhouse gas. Inevitably the use of fossil fuels as a source of energy will end and any sources of methane used for energy could be utilized for fertilizer.
Quote:
On the one hand, as an aspiring petroleum engineer,
Then you should understand peak gas/oil, yes? That doesn't mean those resources are no longer in the ground, it means the energy expense to get them out of the ground exceeds the energy they provide. As other forms of energy become feasible those resources become exploitable just for their chemical properties. Of course that is not infinite supply but it extends that supplies usefulness far beyond energy uses.
I am aware of peak oil/gas, yes, which is why I talked about it with calling it by name. I was saying that we can choose to stop using petroleum for many uses because it's no longer economical, but without a replacement source of hydrogen, we would be forced to keep going past peak gas because the need to eat, no matter how expensive, is constant.
I was already thinking about how hydrogen is found in plenty of other sources. My main curiosity was pretty much trying to figure out if any other alternative is simply delaying our inevitable doom. As I read from the book, so long as our population is this high, we must use artificial ammonia production of some kind. If the hydrogen for that comes from, let's say, water, I would imagine there would eventually be a water shortage.
Your mentioning of the methane sourced from livestock and humans is not something that had occurred to me, but don't conservation laws and a less than 100% efficiency in all processes make this also unsustainable? After all, the methane from animal waste comes from their bodies chemically altering their food, the food being something we have to grow with the use of fertilizer.
Yes, a major rate limiting step in food production is the availability of biologically active Nitrogen. While N2 makes up 70% of our atmosphere, O2 makes up 21%--so our atmosphere is an "oxidizing" one--any free NH3 is quickly converted to N2 + H2O....To get N into a useable form, it must be "fixed" by nitrogen-fixing bacteria (clever name) in the soil (most efficiently located in nodules growing on the roots of legumes and a few other types of plants). They make NH3 which is then turned by nitrifying bacteria to nitrous acid and that into nitric acid, which can be absorbed and used by plants.
Animals then eat the plants and use the N. They re-cycle it by turning it into urea in the liver and then excrete it in the urine. Once excreted, the urea quickly degrades to NH3, a very volatile substance, so it doesn't remain in the soil very long.
There is very little N in manure. My hoses' manure only tests out as "adequate" on those cheapo test kits-- ie-- not any better than the soil it came out of, so it's use as fertilizer is really limited ( Cf- your high school algebra "mixing problems"). ...Use of manure can only increase the N content of soil if you bring in "outside" manure. If you do that, you can increase the N in that field, but decrease the N in the source pasture. That's the chemical equivalent of energy's 2nd Law. BTW- the reason chicken manure is so good is cuz they excrete both GI waste & renal waste thru the common cloaca- ie - it's really low N manure + hi N urine.
The Treehuggers always whine about "sustainable Ag." In reality, only hi tech, industrial ag is sustainable (at least as long as the sun shines or lava is hot)….Just look at the Dust Bowl experience (basically organic farming) the depletion of the Fertile Crescent & N.Africa early in human history or early American pioneers who quickly farmed out their plots and had to keep moving west.
Some simple math: prior to WW II, all farming was "organic" and a good yield of corn was 50 bu/ac. Today any farmer in IA who doesn't get 175 bu/ac hangs his head in shame. Many reasons for the increase, but the Haber process is the main one.... Even crop rotation (corn & beans, a legume) won't give you enough N for sustained yields.
As long as we can put energy into the Haber process at a price low enough to keep the economics of supply/demand viable, there won't be a problem....But I wouldn't worry about it anyway-- our national debt will be the factor that brings down The World Order and cause a major Die-Off long before we run out of petroleum (either that or an Invasion by Zombies)-- not that I'm a pessimist or anything like that
BTW- in case you didn't realize it-- Hubbert's Pimple (Peak Oil) is a graph of the derivative of the logistic equation-- that well known sigmoid shaped growth function graph. The peak of the pimple corresponds to the inflection point of the growth curve.
As I recall from my college ecology prof in 1990, Malthus theorized in the 19th century that while population grows expodentially, food supply only grows geometrically. He theorized that the world was facing a massive famine.
So what happened? The Industrial Revolution. The IR changed things so there was more food available and the population GREW.
Now, if one takes the energy, such as oil, out of food production (looking at all of it, not just agriculture), WATCH OUT!
You know, it is not just pesticides, it's not just refrigeration, it's not just irrigation, it's not just transport farm to market, it's not just shipping fleets, and so forth. There is so much energy tied into food production, that it is rather frightening of people who don't understand that when they think we can just stop using oil.................
............................like that teenager recently at the UN. She may be bold but I believe she is very, very clueless.
There is another important piece of the food puzzle few people know about and that is peak phosphorus.
Phosphorus is the P in fertilizer [N-P-K] and is essential to food production. There is a limited supply of P available and when it runs out there will be no more mass food production. Current estimates have supplies being depleted in 50-100 years. We will be forced back to subsistence farming and there will be mass starvation on a global scale and probably wars fought to gain control of the remaining supply. It is a crime that some people eat enough food for 2 or 3 people and using corn for ethanol is absolutely insane when this is factored in.
Phosphorus never disappears like oil but it must be recycled back to the soil through our waste and by composting all plant material.
There is another important piece of the food puzzle few people know about and that is peak phosphorus.
Phosphorus is the P in fertilizer [N-P-K] and is essential to food production. There is a limited supply of P available and when it runs out there will be no more mass food production. Current estimates have supplies being depleted in 50-100 years. We will be forced back to subsistence farming and there will be mass starvation on a global scale and probably wars fought to gain control of the remaining supply. It is a crime that some people eat enough food for 2 or 3 people and using corn for ethanol is absolutely insane when this is factored in.
Phosphorus never disappears like oil but it must be recycled back to the soil through our waste and by composting all plant material.
Not just to gain control of the remaining supply but probably to reduce the population to reduce the demand.
Previously when ever I have mentioned 'peak oil' on this forum, I have been amazed at how many trolls come out to shout me down.
As an organic farmer, my focus has obviously been on producing food for myself and my customers. At this point, I have not seen anything to imply that I will not be able to continue producing food indefinitely. But of course, I am not a part of the commercial/industrial food manufacturing economy.
There is another important piece of the food puzzle few people know about and that is peak phosphorus.
Phosphorus is the P in fertilizer [N-P-K] and is essential to food production. There is a limited supply of P available and when it runs out there will be no more mass food production. Current estimates have supplies being depleted in 50-100 years. We will be forced back to subsistence farming and there will be mass starvation on a global scale and probably wars fought to gain control of the remaining supply. It is a crime that some people eat enough food for 2 or 3 people and using corn for ethanol is absolutely insane when this is factored in.
Phosphorus never disappears like oil but it must be recycled back to the soil through our waste and by composting all plant material.
Re: Phosphorus-- a dilemma-- without using it, yields are lower, but we use it inefficiently and run-off to our waterways can cause eutrophication. Here in WI, we are loaded with hi natural soil levels and regs ban us from using it....Apparently size of world supplies are debated-- 50 -300 yr's worth (??)
Re: gasohol-- a classic political boondoggle/pork legislation. 10% ethanol/gasoline mix gets 10% worse mileage than 100% gasoline (just a coincidence that 10% number appears twice)-- that means for a car getting 20mpg on gas, a switch to gasohol would save 1 gal of gas for every 100 used ...Gas was on schedule to last 100 ys. Now with gasohol mandate, it will last 101 yrs. (BFD).. For perspective, you can achieve the same fuel savings just by keeping your tires fully inflated.
Re: organic farming-- prior to WW II, there were close to 50 farmers for every50 city slickers. Now USDA claims it's 1:50, but even that's inflated because so many people claim to be "farmers", meeting some bare minimum requirement, just for tax purposes.
While Submariner apparently makes a decent living off organic ag, he's not supplying too many people with food compared to the industrial operations....We can argue about whether our current population is good or bad for the environment, but the fact is, it IS this big and we all have to be fed. It can't be done "organically."
RE: peak oil-- was about to turn into a huge problem. Twenty y/a, we were on course to deplete oil in 50-100 yrs. We discussed on another thread here recently how impossible it would be to work fields with EVs...But fracking has since become economically viable and we now have enough oil/NG to last us several more centuries.
Re: gasohol-- a classic political boondoggle/pork legislation. 10% ethanol/gasoline mix gets 10% worse mileage than 100% gasoline (just a coincidence that 10% number appears twice)-- that means for a car getting 20mpg on gas, a switch to gasohol would save 1 gal of gas for every 100 used ...Gas was on schedule to last 100 ys. Now with gasohol mandate, it will last 101 yrs. (BFD).. For perspective, you can achieve the same fuel savings just by keeping your tires fully inflated.
It's actually worse than that. I did a real world test some years ago, on a MC trip from New England to Texas. With no fuel gauge, I have to keep track of my mileage so that I know when to refuel...if I wait for the low fuel light to come on I could be much further from a gas station without adequate gas to get there. Long story short, I started on straight gas and as I went west I encountered increasingly higher ethanol mixtures- 5% to 10% to 15%, and as the ethanol increased my mileage decreased...significantly. When I did the math, it showed that I was using *more* gasoline with ethanol mixtures, than I would have used running straight gas.
Then you have to add in the diesel fuel used to plant, tend and harvest the corn. After that, you have to add in the fuel used to mash and ferment the corn, and *then* you have to add in the fuel used to distill the fermented product into a concentration high enough to burn. The whole thing is a massive fraud that costs us much more than the alleged 'benefit'.
And, to add insult to injury, corn being diverted to ethanol production reduces the supply available for food production, which raises the price and in turn increases food costs.
Please register to post and access all features of our very popular forum. It is free and quick. Over $68,000 in prizes has already been given out to active posters on our forum. Additional giveaways are planned.
Detailed information about all U.S. cities, counties, and zip codes on our site: City-data.com.
Please register to participate in our discussions with 2 million other members - it's free and quick! Some forums can only be seen by registered members. After you create your account, you'll be able to customize options and access all our 15,000 new posts/day with fewer ads.
