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Vertical farming does not save space

lowtechmagazine.com

181–190 of 464 posts

Re: Vertical farming does not save space

#181
There is lots of land, at least in the USA, covered in parking lots, buildings, roads that would be excellent places for solar panels. But acreage of cultivated land peaked in the Fifties. We could till far more land than we do now. In the USA, vertical farming is a solution in search of a problem.

Re: Vertical farming does not save space

#182

Earlier quoted context omitted.

That's the whole land belonging to the site, most of which is nature, not the plant itself, which looks like less than 200 acres, including the car parks. In any case, it's not close at all either for that specific example or in general, not least considering that a nuclear plant can produce 24/7 and that solar often does not reach peak production because of the weather. " A solar PV facility must have an installed c…

But surely they don’t just own the “nature” land for the fun of it. I assume it could not be used for other things, like housing, or another nuclear power plant!

The difference with solar/wind space requirements is so big that it does not matter.

If the land is reserved and left to nature that is still a positive thing because that helps the environment and biodiversity. But I'm sure that they could put solar panels on it if they wanted.

The point is that this land is not required for production and in any case solar require much, much more land, so, no, it's not even close.

Re: Vertical farming does not save space

#183
post #116

Earlier quoted context omitted.

Commercial nuclear takes up a lot of space, to the point where replacing it with solar is surprisingly close. For example the the Brunswick nuclear power plant in North Carolina, covers 1,200 acres or 4,860,000 square meters for 1,858 MW = 382 w/m2. It’s stated lifetime capacity factor is 75% which is much higher than solar, but that’s ignoring the long construction and decommissioning process afterwards. You can fin…

You're saying that a couple of 50 year old reactors when including a safety zone and adjusting for lifetime capacity outputs about twice the maximum power of commercial solar panels before adjusting for capacity factor. When you adjust PV for capacity factor the difference ends up at over an order of magnitude.

Thought: Put PV inside the "safety zone" to increase output and use "unusable" space.

Re: Vertical farming does not save space

#184
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…

Or maybe something like what's being investigated for greenhouses on Mars (which gets less than half the sunlight that Earth receives) using mirrors and optical fiber cables to redirect light.

Re: Vertical farming does not save space

#185
post #116

Earlier quoted context omitted.

Commercial nuclear takes up a lot of space, to the point where replacing it with solar is surprisingly close. For example the the Brunswick nuclear power plant in North Carolina, covers 1,200 acres or 4,860,000 square meters for 1,858 MW = 382 w/m2. It’s stated lifetime capacity factor is 75% which is much higher than solar, but that’s ignoring the long construction and decommissioning process afterwards. You can fin…

You're saying that a couple of 50 year old reactors when including a safety zone and adjusting for lifetime capacity outputs about twice the maximum power of commercial solar panels before adjusting for capacity factor. When you adjust PV for capacity factor the difference ends up at over an order of magnitude.

You’re skipping permits +construction ~10 years and decommissioning which seems to take 30+ years on average though few have actually finished the process. https://en.wikipedia.org/wiki/Nuclear_decommissioning

75% capacity factor * 50y / (50y + 10y construction + ~30y decommissioning) = 42% capacity factor which is higher than solar but not by that much.

But let’s assume you’re at a 1.5x capacity factor advantage. So 1.5 GW of solar = 1.0 GW of nuclear. 1.5GW / 220w/m2 = 2.9 square miles of panels plus panel spacing and whatever infrastructure is needed. Double it to be really pessimistic and your under 6 square miles.

Re: Vertical farming does not save space

#186

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…

Don't know how old you are but it's very likely that your children or their children will get old before fusion energy becomes reality.

Re: Vertical farming does not save space

#188
post #165

Earlier quoted context omitted.

I don't know about commercial by 2030 but leap frogging ITER doesn't seem far fetched at all because of the all signficant advances in superconductors achieved after ITER was planned out. Also, if the new superconductors do work out, it's very likely that all other forms of energy generation and grid level storage will become almost immediately obsolete and any additional focus moving forward would be only on improvi…

I'm a nuclear engineer working at a laboratory known for fusion research. Commercial fusion power at any scale is not happening by 2030. 2040 or 2050 are more realistic and may still be a stretch.

That's interesting, do you think that SPARC and HTS advancements like for example VIPER cables point towards a faster path to market for fusion than ITER?

Re: Vertical farming does not save space

#189

This article is more about indoor farming than vertical farming (is it even vertical if there's only one row?). I grow lettuce indoors. It serves as a nice houseplant and fresh source of salad greens for lunch. It's fairly new, so the cost isn't that much different than just buying lettuce. Once I start building my own "pods" instead of buying the brand-name pods, though, I expect it'll be a bit cheaper than buying 4…

Have you written comprehensively about the system you've set up and how it works? I've thought about a Zipgrow system or similar: https://shop.zipgrow.com/products/small?variant=316809164227... , but, as you can see, it's fairly costly to set up. I don't think it'll be cheaper than the grocery store, but it also seems fun and like the final product may taste better.

I haven't written about mine, but I built one using an aquarium pump, a couple of food grade bus tubs (the kind wait staff use to clear restaurant tables), a couple LED panels, and some basic plastic cups. I grow basil, lettuce, bok choy, cilantro, and it doubles as a good setup for getting vegetable starts going in early spring. It was probably a couple hundred bucks to get going, but it's low maintenance and I get produce and herbs on demand.

Re: Vertical farming does not save space

#190
post #74

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.

Right, which is why it doesn't make sense yet for countries like the US, where there is enough open land and connective infrastructure to grow plants with free sun energy.

If you were to use solar, then you'd need a country that has a lot of land that would be better used on solar panels rather than farmland, so maybe one that is mostly tundras or deserts.

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