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Vertical farming is just not viable for low value crops. Compare it to traditional farming where you’ve got:

- free water from rain

- free energy from the sun

- dirt that’s just there which you put the seeds in

With vertical farming you have all the expenses of regular farming, plus the cost to build a building to put it in, plus the cost for hydroponic solution, plus all the scaffolding, climate control, lighting, etc etc

You also have higher land value near cities. Farmland is cheaper far away from commercial centers.
Climate change will care about these. Also if they had to pay for negative externalities, I’m quite sure it wouldn’t be that cheap anymore when you compare the two cases.
Maybe pest and weed control is cheaper in vertical farming?
The opposite. Try to push a weed in a windy wall at 30 m high

If they use vertical farming to breed lattice they are just doing it wrong. There are much better uses for that.

Sun and rain are not so necessary as it seems. Many plants love shadow, and every building has a system to move water up and let it fall later. Green walls could gladly act as a first filter to help recycle part of the liquid human waste produced on a skyscrapper. We are yet diluting it before, so... why not modernize it adding a mesh of capillary roots in the way down?

Putting this walls in special areas out of the way, even shadowed areas, is totally doable even in desertic areas. Just a matter of design. This walls would store water, boost biodiversity and generate a local climate.

Not to mention that in many parts of the world, the 'free' rain/sun/soil are far from a given.
>Vertical farming is just not viable for low value crops.

Is anybody suggesting it is?

I have met many otherwise very intelligent people who get caught up in the coolness of the concept and technology without recognizing how efficient regular mechanized farming already is.
For little green stuff for expensive restaurants, vertical/urban farming is probable economically viable. For marijuana (retail sale price >$100/pound), it certainly is.

But if you imagine that you're going to feed an urban area from vertical/urban farms - well, the wholesale price of a bushel (60 pounds) of wheat has fluctuated between ~$4 and ~$12 over the last 15 years - so between 7 and 20 cents per pound.

How many orders of magnitude below vertical farming's best-case scenario is that? And how much waste heat would staple-growing vertical/urban farms need to get rid of, in global-warming cities, where the poor are already dying from the heat?

Nobody is going to use vertical farming to grow bushels of wheat.

I think the general idea is that it can be used to grow fresh produce with a short shelf life which require fragile and expensive just-in-time logistics to get to your plate before going bad.

The fact that expensive restaurants are already using it to produce fresh produce is probably a sign that it can be made mass market if costs can be reduced. The produce is fresher and not spritzed with pesticides. Isn't that preferable?

This is all quite plausible, especially as solar/wind is leading to more periods of very very cheap or even free energy, the automation is getting better and the tech is falling in price.

> Nobody is going to use vertical farming to grow bushels of wheat.

True.

But re-read the first paragraph of the article, especially the "they wanted New York City to be able to feed its population entirely on crops grown within its own geographic limit." bit. The article seems to be built upon utterly delusional assumptions.

> And how much waste heat would staple-growing vertical/urban farms need to get rid of, in global-warming cities

Alternatively, how 'bout in Scando ?

If we assume that new nuclear power plants will not be located close enough to conurbations to supply district heating, then how else to effectively use the waste heat ?

I live in one of the leafiest subtropical cities in Australia

For designers and planners interested in these ideas, please remember to account for increases in frequency in natural disasters over the coming century

It wasn’t that long ago that our nation’s capital, Canberra, almost burnt down from bush fires

Ideas like ground level parklands with high rises over the top do make me concerned about potential mass casualty events from a metropolitan bushfire

Fire fighting resources (like all) are finite

Black summer and the previous Canadian summer bushfires really should drill home the need to consider worst case scenario performance for buildings and urban planning design patterns

I’m sure this article makes great points too, but I had a hard time reading past this in the intro:

“As Despommier notes, the world’s cities make up two per cent of the Earth’s surface but produce sixty per cent of the planet’s greenhouse emissions.”

…as though that is some kind of “gotcha” for cities. But it’s like complaining that oceans make up only 70% of the Earth’s surface but contain almost 100% of its water! Forests cover only 30% of the land surface but contain almost all of the trees!

Cities produce 60% of the plane’s greenhouse emissions because that’s where people live, and it’s people who produce greenhouse emissions. It’s not an amazing argument for urban farming, it’s a tautology.

I've come to the conclusion that vertical farming is uneconomic. It requires lighting, which costs money. The infrastructure is elaborate, too. I don't see how that is going to beat traditional farming.
Indoor farming that works is greenhouse style farming, like in the netherlands, the second largest exporter in the world.
Isn't vertical farming just multistory greenhouses with artificial light?
One kind does VC hype waves followed by bankruptcy and the other kind allows one of the smallest countries in the world to be second top exporter. So there's some difference.
Yes, which removes the main benefit of greenhouse farming.
But not the only benefit I presume? And in scenarios where energy has a negative price using sun directly is no longer a benefit.
> I don't see how that is going to beat traditional farming.

After we've destroyed the environment enough traditional farming won't be an option.

I don’t subscribe to the doomsday ideology but even if I was, it’s hard to see it economically viable. Greenhouse farming is already viable for a lot of crops and would make a lot more sense if the environment no longer allowed for traditional farming.
It’s theoretically impossible to save space with vertical farming if the power is to come from a renewable resource: https://solar.lowtechmagazine.com/2021/02/vertical-farming-d...
You'd need something more efficient than photosynthesis. Directly feeding microorganisms with electrical energy could "work" in this sense. Economics, on the other hand...
This article seems to presume that you'd grow the one heavy crop which can be stored in a silo for years, rather than any of the many crops which go off if they don't get to your table within days and require expensive just in time logistics.

It also presumes that instead of putting all of your wind farms and solar panels somewhere outside of the city and connecting them with this new technology called cables that that you'd put them all on top of your skyscraper.

> It’s theoretically impossible to save space with vertical farming if the power is to come from a renewable resource.

The article talks about only solar panels, but the conventional meaning of your statement would be that it's not possible with any renewable energy. Of course you can use e.g. nuclear or geothermal and save space.

Thinking only from a US perspective, I don’t see these becoming viable. Ignoring even the technology required for these to run, just the vast amounts of land the US has seems to defeat the purpose. Sure you could grow bespoke greens and berries but even that seems like something that could be done in a premium greenhouse facility on the outskirts of a town.

One of my favorite lettuce brands Revol, grows their greens in advanced greenhouses that use less water and lots of technology to optimize the process. This is the future, not vertical. https://www.revolgreens.com/greenhouses/

The whole idea is still really new. Some of the objections being brought up don't necessarily apply. Any building generates a lot of grey water and a drainage issue. Keeping the water local, maybe using some simple treatment techniques, could control the runoff and also make use of it. Buildings usually have one side that gets a lot of sun. There are also many methods being used to advance daylighting including lenses and fiber optic lines. This has so far been expensive, but is competitive with powered lighting systems.

Of course attempts to duplicate existing farms in cities will have issues. Many of these may be resolved. For example, even current farms are beginning to make use of automated weeding and picking machines. This could make it practical to grow in awkward built places that have limited or no safe access.

It is also really important to bear in mind the ugly reality of massive farm failures. When volcanoes blot out the sky for a year or more, which happens every few hundred years, all currently dominant forms of farming fail absolutely and catastrophically. However, in such circumstances some vertical farming setups would have limited challenges. It may be difficult to efficiently and reasonably plan for such scenarios, but we know absolutely that they will happen and it has already been a while since the last really big volcanic event.

His name basically means: apple trees in French... You can't escape your fate...
Do note that recent advances in electrolytic carbon fixation exceed photosynthesis efficiency when coupled with solar panels. So a multi-story farm building who's roof is clad in solar panels would be able to exceed the output of a farm that directly uses the sun, with no utility hookups.

Granted, most nice plants still seem to require some light, but the efficiency advantages over photosynthesis still apply. So maybe use transmissive solar panels to mildly shade the plants, plus hydroponics to deliver the synthetic nutrient solution to them.

Do you have any resources on the latest with electrolytic carbon fixation? Like, how do you go from solar panels -> energy -> plants?
Did he just re-invent suburbs?
Microbe dot tv

Dickson is semi retired now but you can check him and Vincents podcasts, TWiP and TWiV there.

Weird I get downvotes when I think I'm the only one on the thread who had heard of him before.