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Why vertical farms are a crock.

monbiot.com

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Re: Why vertical farms are a crock.

#51

Post by abefortas »

jdietrich wrote: post #26

Farmland isn't just a place to put some plants while they grow. A farm is a giant solar power facility, one that converts solar energy, carbon dioxide and water into carbohydrate. Monbiot doesn't stress the point enough - it's all about light. When we say that we have a shortage of farmland, what we mean in practical terms is that we have a shortage of flat areas with good drainage to function as solar collectors. Go…

I don't know if Despommier suggests this, but mightn't his idea make more sense if the towers were used for growing things like mushrooms?

Re: Why vertical farms are a crock.

#52

Post by DougWebb »

dalke wrote: post #48
kyteland wrote: post #44

Earlier quoted context omitted.

I don't buy his argument that the cost of artificial lighting alone would be ~100x the current market value of the produce, especially when you use the solar collector analogy for farmland. Some quick googleing puts wheat in the 1% efficient range or less when converting light into carbohyrates. I have no idea where to find the exact number but it's not efficient at all. In a controlled environment the remaining 99%…

"In a controlled environment the remaining 99% of the energy could be recycled." Thus violating the second law of thermodynamics. Do tell how we can recycle that energy, turning waste heat back into light, since that would also make solar cells more efficient, increase farming capabilities in cloudy/cold regions, and reduce our dependency on petroleum by making biofuels easier to grow. For a starting point of the cal…

Obviously you just put buckets under the plants to catch all of the light that falls through, and you have a machine that picks up the buckets and dumps them out over the top of the plants again. I think it'll help to paint the inside of the buckets white... or maybe black; not sure. Oh, and the bucket-dumping machine should be solar powered.

Re: Why vertical farms are a crock.

#53

Post by DougWebb »

ars wrote: post #30
1053r wrote: post #9

Earlier quoted context omitted.

Production prices for solar energy are now below $0.80 / watt ( http://www.123jump.com/market-update/First-Solar,-Inc-Q4-Ear... ), although skyrocketing demand has caused wholesale prices to remain much higher. It seems likely that we may in the next 10 years be in a place where we can turn sunlight into electricity, and then electricity into the exact wavelengths of light used in photosynthesis more efficiently than…

How in the world did you get +8 mod on this? That's utter nonsense! You can only get as much light as you have surface area - so now instead of fields of crops, you have fields of solar collectors! Did you think there was some magical light multiplier device that could give you more output light than you started with? Plants already use the best parts of the visible spectrum to collect light. The small amounts of inf…

I think the idea here is that plants need a narrow set of frequencies and throw the rest away. If solar cells could capture the frequencies plants don't use, convert them to energy, then convert the energy to frequencies plants like, you've increased the efficency of your light-collection area.

You'll also have a garden full of black plants, which is both creepy and cool.

Re: Why vertical farms are a crock.

#54

Post by stan_rogers »

rwhitman wrote: post #38
jlgbecom wrote: post #21

Vertical farms are kind of a crock, kind of. The idea of indoor agriculture is not, however (just look at Thanet Earth), and there is an advantage of building up a few floors and using grow lights to supplement the loss of passive lighting. A series of low-rise warehouses using hydroponics in the outer rings of a city makes a lot of sense. However, the architectural games people are playing with huge spires in the ce…

I had always thought that the skyscraper version of vertical farming was more of a fantasy technology. Everything real I've seen is focused on what you mention, low-rise warehouses with racks of hydroponics and skylights - making it essentially a robotic greenhouse. I don't see how this is outlandish

Perhaps improved lighting would make it more effective and efficient today, but I'm reminded of the Sprung Greenhouse in St. John's, Newfoundland. Now, before anybody gets on the "government involvement is bad" bandwagon, try to keep in mind that Newfoundland has next to no agriculture at all, apart from a few root vegetables (it's a rock that alternates between barren land and impenetrable forest) and has always had to import most of its non-fish foodstuffs. Even given the importation expense, the greenhouse production was incredibly expensive compared to the existing supply chain. Putting production into a building doesn't change external light levels or prevent snow from accumulating on top of the greenhouse (or solar panels, reflector arrays, etc.). Even the wind levels were high enough that safe operation of windmills would have been difficult (sustained wind speeds regularly reach levels where normal turbines would be parked and feathered). Not saying that it can't work, just that it won't be cheap (so it's likely that transportation and ordinary production costs will have to rise quite a bit), it won't be easy in a lot of locations, and it's not a panacea.

Re: Why vertical farms are a crock.

#55

Post by sshumaker »

chadmalik wrote: post #43
chadmalik wrote: post #37

Maybe vertical farms are a crock but at least people are starting to realize that local food production is a better idea than shipping factory farm food thousands of miles. Eating local, seasonal food is how it has been done for 99.99% of human history. We waste hydrocarbons in a criminal fashion and our ancestors will absolutely hate our guts for it. Why should we burn up billions of years of oil inside of ~200 year…

I'm seriously tired of getting downvoted for good comments. Later hackernews, have fun with your circlejerk.

Because your comments about local food are clearly written without a basic understanding of the breakdown of energy use. Freight shipping uses about 1 gallon of gas/ton/500 miles. Over 80% of the costs are in the final few miles - trucking from the shipping depot to the markets.

Getting food locally delivered is far less energy efficient than having it shipped in bulk by freight to supermarkets.

Re: Why vertical farms are a crock.

#56

Post by slapshot »

parfe wrote: post #10

Vertical farms are a crock because transport of crops is easy. Moving people is much harder. This is why economic centers are densely populated, but can still eat food shipped from 1000 miles away. There is no reason to spend millions to build vertically when you can buy cheap land and transport the products to the most profitable markets on demand.

This. People should be dense, farms should be sparse.

Taking city land to grow crops is NOT carbon-efficient. The far more carbon-efficient method would be to use city land for more housing, and use suburbia for farms.

Think of it this way: people commute both ways every day, but food commutes only once.

I'm not even going to get into the idea that it's more carbon-efficient to grow bananas in South America and ship them to New York than it would be to heat and light a greenhouse in New York...

Re: Why vertical farms are a crock.

#57

Post by chadmalik »

sshumaker wrote: post #55
chadmalik wrote: post #43

Earlier quoted context omitted.

I'm seriously tired of getting downvoted for good comments. Later hackernews, have fun with your circlejerk.

Because your comments about local food are clearly written without a basic understanding of the breakdown of energy use. Freight shipping uses about 1 gallon of gas/ton/500 miles. Over 80% of the costs are in the final few miles - trucking from the shipping depot to the markets. Getting food locally delivered is far less energy efficient than having it shipped in bulk by freight to supermarkets.

No, it is because the moderation policies on this site are absurd and comments saying "it sucks" get modded up while a reasonable comment gets modded down.

Bottom line the world is running out of hydrocarbons. Things that look "energy efficient" to you today won't look so efficient in 50 or so years. Peak oil already happened in the United States, Hubert's peak is reasonably well accepted, and the idea that shipping food thousands of miles is a long term sustainable strategy for feeding humanity or that the entire world can live like the people in Silicon Valley and New York City is laughable.

That is my last comment on HN - mods, please prove my point by voting it down.

Re: Why vertical farms are a crock.

#58

Post by dalke »

chadmalik wrote: post #37

Maybe vertical farms are a crock but at least people are starting to realize that local food production is a better idea than shipping factory farm food thousands of miles. Eating local, seasonal food is how it has been done for 99.99% of human history. We waste hydrocarbons in a criminal fashion and our ancestors will absolutely hate our guts for it. Why should we burn up billions of years of oil inside of ~200 year…

"Ultimately though agriculture itself is a non-sustainable process. That is why the fertile crescent, cradle of civilization, is now a desert." It was a desert before as well. The Sumerians used irrigation to be able to turn dry but fertile soil into farmland. This requires a lot of hard work, ingenuity, and collaboration, which might be why civilization started there. It's relatively flat, with a hard subsurface, which makes salt buildup a problem, making farming there rather more fragile.

If what you are saying is true, then why is there still farming after thousands of years along the Nile and Indus river valleys?

In any case, what do you suggest the people of L.A. do? They grow a lot of their food locally, in the Central Valley, but that water is pumped from across the state and the Valley has the same problems as the Fertile Crescent.

Should they grow the food in their backyards (more locally), and if so, will there be separate water systems for crops, because it needs less water treatment than humans need?

Or should some large fraction of the population move, and if so, where? Since food forests aren't going to grow well enough in LA to feed its own population, at least, not without non-local water.

Personally, I would rather pay people to grow my food for me while I get to sit on my porch and enjoy reading and commenting on HN.

Re: Why vertical farms are a crock.

#59

Post by dalke »

DougWebb wrote: post #52
dalke wrote: post #48

Earlier quoted context omitted.

"In a controlled environment the remaining 99% of the energy could be recycled." Thus violating the second law of thermodynamics. Do tell how we can recycle that energy, turning waste heat back into light, since that would also make solar cells more efficient, increase farming capabilities in cloudy/cold regions, and reduce our dependency on petroleum by making biofuels easier to grow. For a starting point of the cal…

Obviously you just put buckets under the plants to catch all of the light that falls through, and you have a machine that picks up the buckets and dumps them out over the top of the plants again. I think it'll help to paint the inside of the buckets white... or maybe black; not sure. Oh, and the bucket-dumping machine should be solar powered.

Oh, of course - Maxwell buckets will do the trick! Just need little robots with mirrors on each one to let light in and not let it out.

Re: Why vertical farms are a crock.

#60

Post by eogas »

This is what I hate about the times we live in. When someone comes up with an idea of how to solve a problem, all we do is discuss. We discuss and we discuss. We argue about the plausibility, we may even do some calculations to see how plausible the solution is. But we never actually try it.

In other words, if some guy thinks a vertical farm would be a good idea and a possible solution to a problem, then why the hell doesn't he just, you know, make a vertical farm and see what happens? If it works, then that's fuckin' awesome, we've got vertical farms! If it doesn't work, well then hey, no biggie. Let's try something else.

Of course some problems have very expensive solutions that are not feasible to just "try out", but I don't think it would cost a ton to make a small scale version of a vertical farm. Even if it was only like 10ft by 10ft and as tall as a two story house, you have to start somewhere.

But I guess we'd rather just talk about the possibility, and never take it any farther than that.

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