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Vertical farming does not save space

lowtechmagazine.com

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Re: Vertical farming does not save space

#301

Post by modriano »

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, chard, carrots, tomatoes, radishes, and a bunch of herbs, all in about a 60cm x 60cm x 120cm grow tent. It's much less efficient than it could be (if I had much more space), but it's still extremely productive. My setup draws about 80 watts for 18 hours a day (vegetative growth phase) or 12 hours of day (flowering stage) and I've been able to prolong the gap between grocery store trips because this produces enough to eliminate the need to buy vegetables.

This article is just ridiculous.

Re: Vertical farming does not save space

#302

Post by tohmasu »

Retric wrote: post #268
tohmasu wrote: post #264

Earlier quoted context omitted.

Just no. Reactor buildings take up a small fraction of the total site area. Constructing additional reactors on existing sites has been done for about as long as nuclear power has existed and multiple reactors coexist simultaneously at the same site. >"Replacing panels is just a cost question" Sure, I bet you won't need more than 2 guys and a pickup truck to install, maintain and replace the 120 million panels it wou…

There are actual current contracts that agree to sell solar at under 2c/kWh. Construction of multiple reactors on the same location is very common, constructing a new reactor next to a reactor being decommissioned isn’t. https://en.wikipedia.org/wiki/Crystal_River_Nuclear_Plant https://en.wikipedia.org/wiki/Rancho_Seco_Nuclear_Generating... https://en.wikipedia.org/wiki/Shippingport_Atomic_Power_Stat... https://en.wi…

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, administration etc.

I would presume it's a matter of very few new nuclear reactors being built. Some smaller sites will be decommissioned regardless though.

Re: Vertical farming does not save space

#303

Post by jjeaff »

Guthur wrote: post #294
pfdietz wrote: post #239

Earlier quoted context omitted.

Not. Nowhere has it done well. It's just too complex with too many interdependent parts. Construction has proved to be beyond the competency of those trying to build plants. And now, it's just too late. The iteration time for nuclear designs is measured in decades, going up against renewable and storage technologies iterating in periods of a few years. Fusion would make fission look dead simple. If fission reactors c…

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 the under-generation. Mostly it was issues with coal and nat gas as well as a nuclear plant going offline.

That's not to say that there won't need to be more storage technology or backups for renewables to become a large slice of the power pie.

Re: Vertical farming does not save space

#304

Post by tvanantwerp »

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…

As a new homeowner who has never gardened before, I'm curious how to get started doing something like your hydroponics setup.

Re: Vertical farming does not save space

#305

Post by chongli »

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…

It also doesn't take water into account. You can build solar panels in a desert and send the power over high-voltage DC lines with minimal losses. Trying to pump water into the desert and grow food outdoors, with constant losses due to evaporation, is far less efficient. You also need to bring in fertilizer, fuel to operate equipment, workers, and fuel to ship the harvest back out of the desert to bring it to market.

Re: Vertical farming does not save space

#306

Post by wainstead »

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…

> 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).

I want to stress this point. Crops like wheat, rice, and corn are not suitable for vertical farming. No vertical farms today are growing these.

And claiming “vertical farming does not save land” based on a single 1msq art installation makes a tenuous argument at best.

And even worse, from the article:

> When wheat is planted in the ground next to each other, instead of above, the sun provides free energy and the clouds free water.

No, no, no, no. Water from precipitation is a fraction of the water needed in areas like the American central plains where the Ogallala Aquifer has been pumped out for decades. Irrigation is a must for growing staple crops almost anywhere. And water is increasingly in short supply.

Re: Vertical farming does not save space

#307

Post by sampo »

Ekaros wrote: post #154
tux1968 wrote: post #106

Earlier quoted context omitted.

How exactly do you do that in say the desert? Solar is KISS in many situations.

Some type of semi-reflective coating to keep heat low and closed loop systems? I wonder how expensive and actually complex would it be to find nano-scale substance that would reflect most of wasted light spectrum while allowing the one needed...

Or a solar panel that is transparent to red and blue, and only captures green light?

Re: Vertical farming does not save space

#308

Post by Armisael16 »

wainstead wrote: post #306
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…

> 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). I want to stress this point. Crops like wheat, rice, and corn are not suitable for vertical farming. No vertic…

Why not corn? My understanding is that it’s one of the most efficient crops in calories/acre terms (which is presumably what you actually care about, not kg/acre).

Re: Vertical farming does not save space

#309

Post by wainstead »

ravi-delia wrote: post #161
manicdee wrote: post #18

Earlier quoted context omitted.

If you collect the rain coming down, someone downstream ends up with no water. Water is not free.

Not really, since other than the small amount of water that gets shipped out in the plant, the rest is just released right back out. Besides, as long as you're only collecting the water that falls directly on you as rain, you're not taking any more than your lot; someone 'downstream' can also collect water that falls directly on them.

If you’re talking rain barrels, sure. But some states in America make it illegal for you to collect rainwater on your own property because it legally belongs to someone else.

Re: Vertical farming does not save space

#310

Post by agitator »

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…

Even so, how does free sunlight with longer transport compare to the cost of electricity with short transport.

I imagine electricity, regardless of source, is still the most expensive factor.

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