this post was submitted on 27 Sep 2024
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I really do want to like the idea of vertical farms, and hydroponics in general as there are lots of benefits versus wild growing, but whenever I see some article claiming sustainability or a reduction in climate impact, it's total bullshit.
All of these systems require massive amounts of nutrients to keep the plants alive and producing, and that essentially means all kinds of mining. The byproducts of these facilities are also toxic, and there is no regulation about how they have to manage that...yet. Essentially they are just taking the farm runoff problem and moving it from rural areas where it's already bad, and transplanting it to denser urban areas.
If they could find better ways to streamline the acquisition of the fertilizer components needed for these facilities, and also the treatment or or disposal of the byproduct, these would be a much better idea.
There's no reason it couldn't be a closed system, where any fertilizer that doesn't become part of the crop biomass is recycled. In theory it should be more sustainable than existing agriculture and use less fertilizer per kg of crop produced.
Could be, but isn't, which is where some regulations probably need to come in. I'm familiar with the systems Plenty uses, and it's all automated.
Prime > start > feed > dump once dead
I've not seen another of these large scale startups doing anything different as of yet, which does make sense cost-wise. Any crop you grow won't ever use an exact amount of nutrients at cycle end with a completely neutral byproduct, and trying to reuse what is left would require a lot of expensive lab efforts which they don't care to invest in.
Example: say you start with a 9N-12P-34K solution, and after a month it degrades to 0-0-12. You can't just refill the nutrients with that same mixture you started with, or you'll damage or risk killing the crop with too much Potassium. You'd need to analyze the loop nutrients to know what level you're at for each nutrient, and adjust to get the mixture right to recharge properly. Currently all these systems just dump and recharge because it's cheap (for now) and easy, but these high concentrations of the various components just end up saturating an area the same as farm runoff. Even if you filter, that filtered medium needs to go somewhere.
There are fancier methods of nutrient filtration extraction and recapture just starting to become more feasible, and we should be looking at making sure these are being used for these large operations.
I assume also that the technological side of things is far from perfected, but that will improve over time.
I mean, an urban environment flushes tons of fertilizer down the drain every day...
Human waste is not suitable for fertilizer.
Human waste could be used. It requires more processing to keep it safe, however.
There is also the complecating factor of chemicals. Night soil needs relatively little work. Toilet cleaner, however, needs more processing.
It's currently nowhere close to viable to do in a city environment, that could be changed in future.
/nightsoil has entered the chatYou should probably look up how most of your rice and beans are grown overseas.
See my other replies to this person.
It's not about the feasibility, but about the suitability.
I think a lot of people saw Matt Damon growing potatoes in human shit and thought it was legit and not specific to non-earth soil.
Of course it is. Or do you really think, cow and pig manure is fundamentally different from our shit?
The only difference are some germs, but that can be handled - otherwise water treatment plants would cause epidemics downstream.
It most definitely is not.
https://www.fda.gov/media/117422/download https://en.m.wikipedia.org/wiki/Night_soil
I believe some small pilot programs in EU allowed specific types of TREATED sewage to be used, but that's a whole different thing.
So your argument against treated waste is, that it has to be treated first?
I certainly didn't create the FDA, USDA, or medical science. Doesn't have anything to do with me.
If you want to take a chance on it, go for it, but seems a lot of people who specialize in the field all say you're wrong.
No, and if you would actually read the sources or dare to think for a few seconds you'd see that.
Human waste is not spent uranium that kills for millions of years with no way to mitigate that. If that would be the case, we would literally be drowning in shit right now.
Human feces contain some bacteria that can be dangerous, but that can be dealt with - again, this is exactly what every water treatment plant is doing. What do you think happens with all our shit? Do you think we fling it into space?
We entomb it in massive concrete caskets with a volume up to 5 000m², lined with plastic to prevent leaking, and when it's full we cap it and bury it under 3 meters of dirt.
It used to be around 1-2m wide clay bowls that were filled halfway and there was a variety of methods to cap it off. The reason for famines and things like the black death were people who just buried it in dirt, the cursed crap leeched out.
Runoff from a facility like this would be, in theory, easier to manage since it would be a concetrated source. A pipe of nutrient-rich water rather than a dozen contaminated streams and ponds. That also makes it feasible to recycle a lot of those nutrients, something that isn't practical in a field.
Where I am from, farmland is cheap because of restrictions that prevent development or building on the land to preserve the areas ability to produce food.
But this doesn't prevent the building of greenhouses, since it's considered agriculture.
This results in many hundreds of acres of perfectly fine agricultural land being dug up and covered in gravel and concrete to build greenhouses.
It would be the same for vertical farms I imagine.
That's fucked up. I can see it tolerated at very small scale, but if it goes above 10 acres in any state or small country, it's a bit more than I'm comfortable with.
you forgot to mention energy use. we have to simulate the sun and that aint cheap.
Well the power usage can vary depending on the setup. Some of these bigger facilities actually use sunlight, and there are other configurations that I've seen that plan to convert rooftops into growing spaces. The pump equipment takes quite a bit as well.