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Vertical farming does not save space

lowtechmagazine.com

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Re: Vertical farming does not save space

#121

Post by datenwolf »

kibwen wrote: post #7

> Artificial lighting saves land because plants can be grown above each other, but if the electricity for the lighting comes from solar panels, then the savings are canceled out by the land required to install the solar panels. This doesn't have to be the case. Plants don't use all the sunlight that hits them, because available light isn't generally the bottleneck in plant growth. Note how most plants are green, whic…

There is this recent-ish paper (DOI: 10.1126/science.aba6630) on why it might be, that plants forego the peak of the solar spectrum. Essentially it boils down to being able to regulate the photochemistry of photosynthesis. If it were centered on the peak of the spectrum there's not a lot of regulation possible by means of shifting the reaction energy levels around.

By placing the light absorbing parts of photosynthesis on the slopes of the spectrum, by mere adjustment of the energy levels the reaction undergoes it can shift its activity to parts of the spectrum with more or less light intensity.

Re: Vertical farming does not save space

#122

Post by mytailorisrich »

tux1968 wrote: post #74
maxharris wrote: post #59

Artificial lighting saves land because plants can be grown above each other, but if the electricity for the lighting comes from solar panels, then the savings are canceled out by the land required to install the solar panels. The vertical farm is a paradox unless fossil fuels provide the energy. In that case, there’s not much sustainable about it. This entire piece is based on the assumption that the only sources of…

The other thing to remember is that there is a lot of land that isn't suitable for farming for one reason or another that can be used for solar.

Considering the pressure on the environment and biodiversity, and the disappearance of wilderness, I think we don't necessarily want to exploit more land.

IMHO a key point of the article is that solar is not really a suitable source of electricity for vertical farming. There are other sources of clean electricity that more suitable in order to reap the benefits of vertical farming (less transport and less use of land, and also less water and pesticides).

Re: Vertical farming does not save space

#123

Post by hansvm »

dragontamer wrote: post #113
tux1968 wrote: post #74

Earlier quoted context omitted.

The other thing to remember is that there is a lot of land that isn't suitable for farming for one reason or another that can be used for solar.

> lot of land that isn't suitable for farming We're talking about powering a hydroponic greenhouse. The alternative to "Solar Powered LEDs" isn't "plant things in the ground". Its "make a glass window on your roof". -------- "Plant things in the ground" is also cheaper, though it does suffer from potentially poor soil conditions. Still, it seems to me that spreading fertilizer across soil (and conditioning the soil i…

> lot of land that isn't suitable for farming

> We're talking about powering a hydroponic greenhouse. The alternative to "Solar Powered LEDs" isn't "plant things in the ground". Its "make a glass window on your roof".

I think what they were getting at is that you can take land wholly unsuitable for farming or greenhouses (e.g. severe slopes), apply solar panels, and then funnel that energy to a vertical farm. Since the vertical farm does save space in the abstract (just not necessarily once accounting for space needed for electricity generation), the scheme overall is still a more efficient use of land.

Re: Vertical farming does not save space

#124

Post by ratsforhorses »

LatteLazy wrote: post #108

I feel like this whole thing is like arguing over how many angels can dance on the head of a pin. We have a shit tonne of land. And we already grow vastly more food than we need. So why do we care? Aside from maybe building farms on Mars, what is the expected use of this tech?

Lack of diversity and vegetables are expensive ; the former leads to overuse of all those "-ides"(and fertilizer) and the 2nd to the obesity epidemic, because derivatives from corn are so much cheaper...

Re: Vertical farming does not save space

#125

Post by jasonwatkinspdx »

kibwen wrote: post #7

> Artificial lighting saves land because plants can be grown above each other, but if the electricity for the lighting comes from solar panels, then the savings are canceled out by the land required to install the solar panels. This doesn't have to be the case. Plants don't use all the sunlight that hits them, because available light isn't generally the bottleneck in plant growth. Note how most plants are green, whic…

> Note how most plants are green, which is to say they're content with reflecting the most energy-dense range of the visible spectrum.

Photosynthesis is very complex, and there are reasons why plants shed about 10% of green light: https://science.sciencemag.org/content/368/6498/1490 . It's not that evolution was too dumb to discover the simple fact of green light being more energy dense, it's that there's other more important constraints happening at the molecular level in photosynthesis.

Re: Vertical farming does not save space

#126

Post by skissane »

maxharris wrote: post #59

Artificial lighting saves land because plants can be grown above each other, but if the electricity for the lighting comes from solar panels, then the savings are canceled out by the land required to install the solar panels. The vertical farm is a paradox unless fossil fuels provide the energy. In that case, there’s not much sustainable about it. This entire piece is based on the assumption that the only sources of…

> If we look into the relatively near future, fusion energy is going to account for a rapidly increasing share of energy production by the end of this decade.

I really don't think by the end of this decade there will be any commercial fusion production. I'm sure we will be closer but it is still some decades away.

ITER proposes to follow up their current research reactor with a successor (DEMO) which they plan to start building around 2040 and begin operating in the 2050s. Then they expect DEMO to be followed by their first commercial power station, PROTO. They probably won't even start building PROTO until the 2050s or 2060s, so we could easily be looking at 2070-2080 before it comes online.

Now, there are other teams working on fusion, there is always the possibility some other team could leapfrog ITER. It is also possible that with increased investment timelines might come forward. But I'm very confident that come 2030, the amount of fusion power in the commercial energy markets is going to still be zero.

Re: Vertical farming does not save space

#127

Post by bee_rider »

Ekaros wrote: post #85
bee_rider wrote: post #68

Earlier quoted context omitted.

The cost of transporting the conventionally grown plants would have to be accounted for as well, but I'd be pretty surprised if that got anywhere near tipping the scale over to vertical farming.

I wonder if that could be solved more easily. Build sufficient rail network and hydrogen/electric/other zero-carbon trucks to move produce from production to there and then train it in. And this is really a sector we could fully automated almost already.

Also, building a zero-carbon transport system would be generally useful for transporting things other lettuce. And that's probably like 80% of the way toward a zero-carbon transit system. I think you have a good point.

Re: Vertical farming does not save space

#128

Post by throwaway894345 »

cbmuser wrote: post #66
maxharris wrote: post #59

Artificial lighting saves land because plants can be grown above each other, but if the electricity for the lighting comes from solar panels, then the savings are canceled out by the land required to install the solar panels. The vertical farm is a paradox unless fossil fuels provide the energy. In that case, there’s not much sustainable about it. This entire piece is based on the assumption that the only sources of…

Yeah, don’t bother with reading articles that exclude the largest source of clean energy in US. Such articles have an ideological bias.

They might have an ideological bias, but if the prevailing ideology is anti-nuclear then ignoring that bias isn't going to get you very far. Biden has committed us to moving the energy sector off of carbon in the next 15 years, which means we're going to build a lot of $CleanEnergy really soon, and if the ideological landscape doesn't change it very likely will be a whole lot of solar and wind (what is 15 years minus the amount of time it takes to build out a nuclear power plant?).

Re: Vertical farming does not save space

#129

Post by hobofan »

kumarski wrote: post #111
maxharris wrote: post #59

Artificial lighting saves land because plants can be grown above each other, but if the electricity for the lighting comes from solar panels, then the savings are canceled out by the land required to install the solar panels. The vertical farm is a paradox unless fossil fuels provide the energy. In that case, there’s not much sustainable about it. This entire piece is based on the assumption that the only sources of…

Way overshooting the confidence on fusion here.

Yeah, last time I checked everyone was still on the "viable fusion is constantly 20 years away" meme.

Re: Vertical farming does not save space

#130

Post by marshray »

charlesju wrote: post #98
marshray wrote: post #80

Earlier quoted context omitted.

Yes, please include the cost of nuclear power in the considerations. (The joke here is that the true cost is undefined because we here in the US have no method to store the long-term hazardous waste it produces. Current cleanup costs for just the military reactor waste are estimated at $500B, for civilian reactors the costs are said to be higher.)

1. We have nuclear waste already 2. We will continue to have nuclear waste if we want to have nuclear weapons 3. You can store all the waste you need to store in a football field ( https://www.energy.gov/ne/articles/5-fast-facts-about-spent-... ) Nuclear waste management is messy, but it's something we need to solve no matter what. It is now a sunk cost we have to deal with because of what we have already done and wh…

Rarely does one hear the sunk cost fallacy advocated so enthusiastically.
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