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Vertical farming does not save space

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Re: Vertical farming does not save space

#371

Post by klodolph »

AngryData wrote: post #333
klodolph wrote: post #28

Earlier quoted context omitted.

Solar panels can be more efficient, but if your comparison is between “sunlight -> plants” and “sunlight -> solar panels -> electric lights -> plants”, you have to include the actual efficiency of e.g. photovoltaics and LEDs in your calculations. Photovoltaics these days have something around 15-20% efficiency and LEDs have conversion efficiency around 50-60%. The magenta grow lamps are colored for more efficient use…

Blurple and magenta LEDs seem to be on their way out last time I looked into growing lights. It is white (or white appearing) LEDs now, which are getting 190+ lumens per watt. The light spectrum is still tuned for plant growth efficiency, but it is a broader spectrum per LED rather than more specific spectrums from specific diodes. It is worth noting too that these newer white LEDs are spectrum efficient enough that…

190+ lm/W is still less than 50% efficiency. I don't understand how a white lamp can be tuned for plant growth efficiency, could you elaborate?

Re: Vertical farming does not save space

#372

Post by Ekaros »

osacial wrote: post #351
yongjik wrote: post #58

Earlier quoted context omitted.

You can also have an airport in the middle of a city and an apartment complex in the middle of the desert - there's nothing that stops them technologically. The problem is that they don't make economical sense.

Vertical farm in a city fits in economical sense, as their market is there, while farmers have to haul their product to consumers.

I wonder does it actually do make economic sense? Like will the net from selling produce be larger than just renting the same floorspace for some other use? Be it residential, office, shops or manufacturing...

Re: Vertical farming does not save space

#373

Post by coldtea »

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…

>fusion energy is going to account for a rapidly increasing share of energy production by the end of this decade

Like it did "by the end" of 4-5 previous decades...

It's the perennial "soon" technology...

Re: Vertical farming does not save space

#374

Post by Ekaros »

soheil wrote: post #332

It may not save space overall, but does it save horizontal space in favor of vertical?

No, that is entirely the point. It does at point of production. But as overall it uses lot more horizontal space. And also space used is much more infrastructure intensive.

Re: Vertical farming does not save space

#375

Post by tohmasu »

Retric wrote: post #321
tohmasu wrote: post #302

Earlier quoted context omitted.

Please link. I've read about some far future contracts relying heavily on public subsidies but even those were at a higher price. At that price, earnings would (depending largely on geography) be something like 160-400 USD / 1.8m² panel over a 20 year period. This needs to cover panel cost, inverters and electrical infrastructure, installation&decommission, land rent, loss due to some prematurely dead panels, adminis…

Subsides are common for all forms of electricity generation, but LA’s 2019 1.997c/kWh power purchase agreement is hardly the far future. https://www.pv-magazine.com/2019/06/28/los-angeles-seeks-rec... Anyway to use a specific example Capacity factor 26.6% (average 2015–2018) https://en.wikipedia.org/wiki/Topaz_Solar_Farm . Bulk panels are $0.29 per W or 290$ per kW. PS-P72-330W https://sunelec.com/ If 1kw is worth 0.…

>"0.01997 $/h * 24 * 0.266 * 365 * 20 = 930$"

That's a calculation based on 1kW of installed capacity, which is about 3 of those 345W panels so the earning per panel over its lifetime (in sunny southern California btw) is about $310.

Also the $ sign goes in front of the number.

Re: Vertical farming does not save space

#376

Post by Rapzid »

perl4ever wrote: post #320
gh02t wrote: post #287

Earlier quoted context omitted.

Stars and fusion nuclear weapons exist. And I'm only half joking. The energy yield of fusion is there and the basic physics are pretty well understood. Progress has been agonizingly slow but steady. We generally understand what needs to be done to get there, but it's a slow and complicated process that will take a long time and several more expensive, large-scale tests like ITER to push it along. The payoff is still…

>barring investment on the scale of the Manhattan project The Manhattan project cost about $30 billion in today's dollars, I believe. We have IPOs that raise close to that amount of money these days (e.g. Alibaba). It's half a percent of federal spending in 2020 (admittedly not a normal year). GameStop has lost over $30 billion from its peak valuation. Your matter of fact claim that there's not enough capital in toda…

Well, ITER will cost 22-65bn. It's much more ambitious than the Manhattan Project IMHO.

Re: Vertical farming does not save space

#377

Post by bastawhiz »

6DM wrote: post #95
worker767424 wrote: post #42

Vertical farming mostly feels like a solution in search of a problem. It uses relatively expensive technology to produce low-value products. Putting seeds in the ground, tilling, and waiting is absurdly cheap compared to building growhouses. For some perspective, what farms actually do extend growing seasons is put "greenhouses" around cold-sensitive crops like tomatoes, but a "greenhouse" in this case is a wire hoop…

Aside from what the other commenters are saying around trucking the produce. Another benefit of growing indoors that you no longer need pesticides to keep bugs from destroying your crops. Edit: also it's supposed to use a lot less water

Regarding water at least, it's a lot easier, cheaper, and less energy-intensive to pump water from a waterways/well and spray it on crops than it is to use water processed and delivered through a municipal system. Plants don't need that's been fluoridated or otherwise heavily treated. Especially since fresh water in most dense urban areas is not very plentiful (with some exceptions), I would find it hard to believe that the decrease in water needs outweighs the lack of availability and cost.

Re: Vertical farming does not save space

#378

Post by bastawhiz »

modriano wrote: post #301

Judging vertical farming based on the performance of wheat is not valid. When I saw the test crop was wheat, I scrolled to see if there were any other crops, saw that there weren't, and abandoned the article because wheat has among the worst yields per area (in terms of kg of edible product per sq meters). Since the pandemic started, I started experimenting with hydroponics and I've been growing basil, kale, mint, ch…

> When I saw the test crop was wheat, I scrolled to see if there were any other crops, saw that there weren't, and abandoned the article because wheat has among the worst yields per area (in terms of kg of edible product per sq meters).

Yes, but corn, soybeans, and wheat represent an overwhelming majority of agriculture (at least in the US). If the goal is to reduce energy use, it makes sense to focus on the things that we're making the most of. In 2013 we produced 354M tonnes of corn and 58M tonnes of wheat, and only 13M tonnes of tomatoes and and 3.6M tonnes of lettuce. The fact of the matter is that wheat—despite being low-yield—accounts for an enormously huge percentage of agriculture.

Re: Vertical farming does not save space

#379

Post by Guthur »

jjeaff wrote: post #303
Guthur wrote: post #294

Earlier quoted context omitted.

And we will soon find out that renewables are not reliable enough and require a higher degree of planning than we are typically good at. Texas recently is a prime example, wind turbines froze and gas turbines had co2 regulations that made it difficult to ramp up. Other issues aside these were major contributing factors and indicative of the challenges many states will have. We can't control the weather and many of th…

Texas's problems have very little to do with renewables. There were some wind turbines that froze, but wind power output overall is actually exceeding projections for this time of year. Not to mention that wind turbines can be winterized to withstand temperatures like in Texas right now. They just didn't because they didn't expect such low temps and it costs money. It looks like renewables accounted for about 13% of…

That's fair. I was basing on incomplete information and retract :)

Re: Vertical farming does not save space

#380

Post by choeger »

airhead969 wrote: post #252
choeger wrote: post #192

Vertical farming will almost certainly not generate the mass of calories to feed the world. But that doesn't mean it cannot be useful. Many vegetables are already grown under very controlled conditions and it doesn't take much fantasy to consider, e.g., tomatoes from a nearby vertical farm more environmentally friendly than their counterparts grown in some remote sunny place. But of course, logistics might get cheape…

Why can't large grocery stores be built taller to grow vegetables horiz/vertical airoponically on an upper level? No need to raise disgusting "pretty" vegetables that are picked green, artificially-ripened, and driven thousands of miles.

Oh they certainly can. But they have to compete against huge greenhouse complexes. So basically you are trading logistics vs. economics of scale. I don't know who would win in every case.
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