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Grain farming goes indoors

modernfarmer.com

111–120 of 124 posts

Re: Grain farming goes indoors

#111

Earlier quoted context omitted.

It's a form of artificial photosynthesis - electrocatalysis-based artificial photosynthesis. We don't need sunlight, or light at all. We can mimic its effects and induce the biological mechanisms to work. For a fodder grass, you only need a few weeks from germination to harvest.

You aren't violating basic physics and thermodynamics being what they are please explain simply where the additional energy comes from?

"electrocatalysis-based artificial photosynthesis"

https://engr.udel.edu/news/2022/06/artificial-photosynthesis...

This should help out some.

Re: Grain farming goes indoors

#112

Earlier quoted context omitted.

"With this method you get the land, then you spend a fortune building a place to house your hydroponic setup, then getting the solution ready, then adding lighting, etc. Also, if you're using solar to power your lamps you're basically capturing sunlight, converting it to electricity, then using that to make fake sunlight for your crops to grow. " With the right crops, the turnaround time goes between 2-5 years for th…

> … way more efficient than the sun. How many kilowatts hours of generated power do you have to put into the sun to get a certain output of photons? None you say? Interesting… This seems like a solution in search of a problem. Just use the land to produce something more valuable than grain and trade that for the grain you need.

If you get down to the actual physics of it all, plants waste so much actual sunlight. It's actually more efficient to harvest the sunlight, store it, and convert back into photons using efficient targeted-wavelength LEDs to just put the amount of light that will get used where it needs to go, and use the remaining power for other things like pumps or atmospheric conditioning.

Nuclear incandescence efficiency - 93 lux/wH - approximately 14% overall efficiency at 6500K.

LED efficiency - narrow-band wavelengths make measuring lux at any wavelength other than green useless, so we stick to overall conversion efficiency, which ranges from ~35% in the red to ~80% in the blue, then we get to phosphor-converted white LEDs using a blue base, which can be compared again to the nuclear incandescence above, and these reach over 200 lux/wH at 6500K, and that was with Cree MK-R LEDs a decade ago.

Then you get into photosynthetic efficiency, which is absolutely dismal in the low single-digit percentage range.

I'll leave the extra math to you. Suffice to say, it's more efficient with decade-old tech to store the sunlight and convert as needed.

Re: Grain farming goes indoors

#113
post #9

Earlier quoted context omitted.

As usual, actual numbers for water/land/pesticide use (5%/3%/0%), but the only mention of electricity use is the fraction of green power. Of course, the use of green power is positioned as an unalloyed good. No mention is made of the fact that every electron used is taken away from the transition from fossil fuels. We're losing ground here, not gaining it. We're supposed to forget that the goal is to increase green e…

And don’t forget the energy and materials you need to build something where you can actually grow things indoors. Total waste of so many things here. We know that we can grow stuff in greenhouses. We know wheat is a cheap commodity too, where it is hard to gain a profit on. What are they trying to accomplish here?

Dunno. In some places agriculture is fried with climate change at the gates so trying things to regain control over culture conditions could worth it. Could be useful also for keeping isolated varieties non contaminated with genetically modified pollen. Just in case something go wrong with that.

Re: Grain farming goes indoors

#114

Earlier quoted context omitted.

You aren't violating basic physics and thermodynamics being what they are please explain simply where the additional energy comes from?

"electrocatalysis-based artificial photosynthesis" https://engr.udel.edu/news/2022/06/artificial-photosynthesis... This should help out some.

The extra energy comes from the electro. Electricity into acetate, then used as 'plant food'. As a substitute for the glucose perhaps?

Re: Grain farming goes indoors

#115

Earlier quoted context omitted.

you have to spray because 1) you still have to use actual soil and thats full of bugs and organisms already 2) if you aren't fertilizing you won't get anywhere near the yield farmers do and you won't be competitive on cost. Harvesting will still require the use of whatever harvesting technology there is. If we can't competitively build grain harvesters with electricity outdoors its unlikely that you'll be able to do…

This article doesn't say, but vertical farms almost always grow hydroponically, using sterilized inert media (like coir) or inherently sterile inert media (like rockwool). The water and fertilizer are delivered together by drip irrigation. Some farms may instead use no medium at all, like in NFT or DWC. With precise control over the plant nutrition, this can achieve higher yields per square foot than soil, making opt…

you're still fertilizing then, its just in the liquid you're using. I suppose that helps against nitrogen runoff which is bad for water bodies so thats a plus.

Re: Grain farming goes indoors

#116

Earlier quoted context omitted.

You aren't violating basic physics and thermodynamics being what they are please explain simply where the additional energy comes from?

"electrocatalysis-based artificial photosynthesis" https://engr.udel.edu/news/2022/06/artificial-photosynthesis... This should help out some.

Radical!

Re: Grain farming goes indoors

#117
post #11

Earlier quoted context omitted.

Not to mention plants are peak "green energy". There is a very real irony to the indoor farming movement.

Not so fast. If you replace outdoor crops with forests, they'll sequester much more CO2. In principle you can replace many acres of outdoor crops with one acre of greenhouse crops: with electric illumination you can make plants grow during nighttime, and with controlled temperature you they can also grow during the winter. Irrigation also needs much less water in a greenhouse (because plants lose a lot of water via t…

Same, I have a green house. I have high tunnels and low tunnels too. They allow my family to grow nearly 100% of our plant needs year round. But I don't grow my grains in a tunnel or a house. I don't grow my pasture in one either. Green houses are a tool and there is a place for every tool. New tools get used for lots of things they aren't good for.

Re: Grain farming goes indoors

#118

Earlier quoted context omitted.

But what if you _couldn't_ farm outdoors, because your outdoor farm is now a dust bowl, or a desert, or a recently inundated coastal plain, submerged by sea water? Financial practicality is not a concern if this is the only way a region has to make food.

You mean the Mad Max universe or Mars?

I kind of mean in places like Saudi Arabia, Saharan Africa, or Phoenix in 20 years or so.

Re: Grain farming goes indoors

#119

I’m skeptical. The problem with grains and hydroponics is that grains are just so cheap it doesn’t make economic sense to do it. Vegetables, particularly leafy greens, are mostly water and can be sold at tremendous markup. I don’t see anything here that changes that economic reality. Even if they were able to double wheat production to 4 crops a year, I don’t that’s enough to make it viable. Most telling is this pass…

"The problem with grains and hydroponics is that grains are just so cheap it doesn’t make economic sense to do it." It makes a ton of economic and ecological sense if you actually break it down. Damn shame the article fails to do so. We knew it made sense a decade ago when I got brought into the field to improve upon the lighting aspects for several companies.

No dude. It does not make economic sense to grow cereal grains. This has been studied multiple times. It costs $20 to grow enough wheat for a single loaf of bread.

https://thehydroponicsplanet.com/can-cereals-be-grown-hydrop...

Re: Grain farming goes indoors

#120
post #92

Earlier quoted context omitted.

Harvesting won't use what? Are you proposing we, as a species, revert to harvesting the equivalent of a few hundred million acres of cultivated land by hand?

It's indoors, probably on many narrowly spaced floors, so you're hardly going to use a combine harvester! There would be some much smaller electrically-powered robotic system.

So now we're proposing to replace an insanely efficient harvesting system that has been refined and perfected over the course of the last century with what? Rasberry Pi's and some off the shelf stepper motors? Best of luck with your endeavor.
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