this post was submitted on 27 Sep 2024
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I don't see how vertical farming can make sense. There is only so much sunlight striking the ground and you just changed the angle and so shaded something else.
Artificial lighting exists.
Sure, but where does the energy for that light come from? If the answer is burning things (this is the most likely answer today!) then you are making the world worse. Renewable answers all go back to the sun so why not use the sun directly and avoid all the inefficiencies from turning the sun into electric and then back into light? Which leaves nuclear - which is dieing because of expense.
Photosynthesis only uses a couple frequencies. Using solar to generate electricity and feed that into target LEDs can be significantly more efficient.
while not wrong solar does not use most of the sun either and what plants use is where a large part of the energy is. Plus your add in the rest of the inefficiencies of the grid. So I'm back to not seeing how this can be enough better.
i'm sure you can grow plants this way I just don't think you can ever make it a good way
Yes, it can come from renewables. There are many ways to build renewables in a way that doesn’t use additional surface area. Like you can have wild nature with wind turbines sprinkled throughout. Solar panels can built on top of most structures humans build anyway.
Vertical farming has the potential to use less land, allowing more wild natural ecosystems.
The controlled environment of vertical farming also allows you to work in a cleaner environment, meaning less need to employ pesticides.
We can also do agrifarming and use the space under the panels for animals to graze or whatever else they've come up with.
Let's assume the energy for lighting comes from solar. Panels are only 20% effective. Now your vertical farm needs 5x the space of a basic farm, and you still have to pay for power instead of using free sunlight. There is some video on YouTube from a salt lake city university professor who works for nasa on growing plants in space about this topic.
Consumer panels are up to 23.5% now, and you can get bifacial cells that can boost that by up to 30%, so up to around 30.55%
Also the light is bouncing around that room, not bouncing off and then back into the sky like it would from the sun, and it's not necessarily all full spectrum, it's the spectrums the plants need, also reducing power compared to what the sun gives it.
Edit: Making shit up now, but what if photosynthesis only needs 30% of the spectrum, and the bifacial panels are 30% it might even be near equal.
https://youtu.be/ISAKc9gpGjw?t=832
You realize that this picture addresses nothing of what I said? It's using 15% when we can get 30%. And still has nothing about what spectrum the plants actually need of what touches them.
Edit: Also a quick search showed 2.9umol/j leds now, and maybe we have higher, so that's up to 870 (3.5x more than image or 62.14% of the sun) hitting the plant now of exactly what it needs instead of 1400 that isn't all what it needs.
Edit: another article from 2017 says the theoretical maximum for LEDs is 4.9-5.1 and we should reach 3.5 within a decade (2027). Also I think I didn't understand the measurement and the 1400 from the sun is the 1400 it needs, but I'm not completely sure.
Also that's 9 years old,
Why are discussing the logistics of such a complex project from such a singular perspective? Its pointless. They probably have their shit figured out.
Sure. The solar panels don’t need to be next to it, but can be anywhere. Solar panels can even be used on traditional agricultural fields while still growing vegetables or grazing animals. Using solar panels on surfaces like roofs or above parking lots is another way of placing them without using additional ground.
Or make a collector and glass pipes in.
Read the article - it's indoors.
That doesn't change anything. unless you have a perpetual motion machine the energy comes from somewhere.
Eh?
On second thoughts, don't bother.
Goodbye.
Vertical farming can make sense. Effectively you capture energy from places or sources unsuitable for farming, and focus it into a small area optimised for farming.
E.g. farming on the side of a building doesn't make sense. Covering the sides in solar panels however is fine. Wind can't grow crops directly. Wind powered grow lights can.
your intuition about insolation is correct, but plants are largely not sunlight limited, rather they are nutrient limited. a vertical farm increases soil density and is also an engineered greenhouse.also in this case the light is from grow lights, so can be powered by say, wind, or nuclear.
some plants are light energy limited but these are often not major crops.