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The Future of Food on Urban Rooftops

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Re: The Future of Food on Urban Rooftops

#31

Post by thecolorblue »

rmah wrote: post #8
ironchef wrote: post #3

Earlier quoted context omitted.

From what I recall reading some of the newer indoor hydro systems (plus LED) were getting greater than 20x increases (I think the lettuce/basil warehouse in Japan was getting over 60 heads of lettuce per square foot in comparison to traditional 3 per square foot in standardized farming). Perhaps by combining some of the different newer technologies they'll get the orders of magnitude of differences.

So why not use these techniques where land is cheap instead of on expensive urban rooftops?

A lot of the waste (at least from produce) comes from every step of the supply chain loosing product to buying to much or letting it sit to long. In theory, growing on a nearby roof could force people to grow only what they are going to use.

Re: The Future of Food on Urban Rooftops

#32

Post by minthd »

legulere wrote: post #24
beambot wrote: post #2

Conventional wisdom says each person requires ~1 acre (43k sq-ft) to source enough foodstuff for themselves. With two people per 1k sq-ft apartment... you need ~100-fold improvement over the conventional wisdom to get full 100% sustainability. So let's assume you can magically get 10x gains in "land use" efficiency, and that you can stack those units 10 levels high (piping 1/10 of the 1kW/m^2 solar incidence to each…

Not all food is equal. Most of the acre (~4k m²) is needed for high energy crops like wheat or rice. It's pretty efficient to transport those into the cities. They can be stored pretty long and are pretty robust for transport. They're also pretty low price. Vegetables and berries are way more interesting as they're the opposite of all those factors.

What's wrong with growing vegetables and berries outside of cities in greenhouses?

Re: The Future of Food on Urban Rooftops

#33

Post by thaumasiotes »

ilaksh wrote: post #22
thaumasiotes wrote: post #16

Earlier quoted context omitted.

Are these techniques likely to be all that different from the techniques used to grow marijuana indoors? I was under the impression that a decent amount of R&D already went toward this.

There is a fair amount of R&D for indoor growing, but not much emphasis on those high-value foods, especially for the most advanced techniques like aeroponics. And marijuana growers don't have the same goals in terms of energy efficiency or cost-effectiveness.

> And marijuana growers don't have the same goals in terms of energy efficiency or cost-effectiveness.

Huh??

They may have additional goals, but they surely share the goals of energy efficiency (this would actually be a much higher priority for them than it would be for legal growers, as you can get caught based on your energy signature) and cost-effectiveness.

Re: The Future of Food on Urban Rooftops

#34

Post by zanny »

minthd wrote: post #32
legulere wrote: post #24

Earlier quoted context omitted.

Not all food is equal. Most of the acre (~4k m²) is needed for high energy crops like wheat or rice. It's pretty efficient to transport those into the cities. They can be stored pretty long and are pretty robust for transport. They're also pretty low price. Vegetables and berries are way more interesting as they're the opposite of all those factors.

What's wrong with growing vegetables and berries outside of cities in greenhouses?

They store shorter and lose a lot more nutrition in transit. They are more expensive to harvest but are more caloric dense in a given area. Its why raspberries are like 5 dollars a pound but bananas are 50 cents. One has a much longer shelf life.

Re: The Future of Food on Urban Rooftops

#35

Post by jmgreen »

asciimo wrote: post #23

Aquaponics proponents rarely mention that you have to feed the fish. The fish are essentially filters that reduce other matter (mostly other fish) into nitrates. An efficient system would remove these inefficient filters and add nitrates directly to the soil. Yes, you can eat the fish. But it takes 240 days to raise (feed) a tilapia to 1 lb of weight. There are cheaper and faster sources of protein. For example, soy…

I'm Jason Green, CEO at Edenworks. And aquaponics evangelist. Here's why we think aquaponics is the best solution to global protein (and vegetable) production.

Tilapia are protein producing machines. They convert 1.1-1.3 lbs of feed to 1 lbs of protein in 9 months (some factors like temperature, feed rate at different stages of life, and other things affect this ratio). But here's the real kicker--by providing the nitrogen that crops need, the crops can then turn CO2 into into calories via photosynthesis. Super high quality produce becomes the extremely valuable byproduct, effectively, of aquacultured seafood.

From a global net energy perspective, this is huge. Where do you think that nitrate fertilizer for soybeans is coming from? The Haber-Bosch process is crazy energy expensive. Growing soybeans for protein also has huge environmental costs--see deforestation in Brazil for details. 80% of cultivable land on earth is already in use, but food production needs to increase by 70% by 2050. Protein production will need to double due to the rising global middle class. And that middle class wants fish.

On top of all that, there's the fact that people don't want to eat just soybeans for protein. There's now more seafood consumed globally than beef cattle. By 2030, 62% of all seafood will be aquacultured, and there are some suggestions that most of the wild seafood species we know will be either extinct or heavily depleted.

Re: The Future of Food on Urban Rooftops

#36

Post by jmgreen »

ilaksh wrote: post #13

Maybe work on high tech ways to grow high value foods like sweet potatoes, soybeans and wheat indoors. Aeroponics with additional support structures maybe.

Jason here, CEO at Edenworks.

Sweet potatoes, soybeans, and wheat are very much the purview of traditional big ag. They're highly commoditized, which actually makes them not very valuable. Compare a pound of flour (not even wheat crop itself @ $0.50 retail) to a pound of salad greens ($10-15 retail) or a pound of basil ($15-45). The reason the latter products are so expensive is because they're delicate. They don't travel well, have high shrink rates, and can be premiumized due to freshness. On a unit basis, fresh and highly perishable foods are the high value food. They're also the most nutritious.

Re: The Future of Food on Urban Rooftops

#37

Post by jmgreen »

ChuckMcM wrote: post #21

This makes a tacit assumption about roof loading, which, by default, cannot support the load of an aquaponics installation (the logical choice). The ability to source some greens locally is useful, but as many have pointed out the win comes when you can locally source something like rice or beans. The water requirements for rice make it especially heavy on a per square foot basis. The folks in Watsonville [1] were tr…

Jason here, CEO at Edenworks.

Roof load is a question we get a lot, and it turns out not to be a dealbreaker if you can distribute weight on the building's columns effectively. Our next greenhouse will be ~ 110 lbs/s.f., which is heavy but nothing a little dunnage can't deal with. On a side note, a research team at Columbia conducted this awesome study showing there's over 5,000 acres of rooftop space feasible for urban farming in NYC (also recommended for any ArcGIS fans): http://urbandesignlab.columbia.edu/files/2015/04/4_urban_agr...

Regarding grains and legumes, you're right and I wouldn't recommend rooftop aquaponics for it - you simply need too much land. I do believe however that urban aquaponics can play a bigger role in supporting a growing, global middle class, which is consuming more vegetables and protein and is especially sensitive to food safety in some regions.

Re: The Future of Food on Urban Rooftops

#38

Post by tcdent »

jmgreen wrote: post #35
asciimo wrote: post #23

Aquaponics proponents rarely mention that you have to feed the fish. The fish are essentially filters that reduce other matter (mostly other fish) into nitrates. An efficient system would remove these inefficient filters and add nitrates directly to the soil. Yes, you can eat the fish. But it takes 240 days to raise (feed) a tilapia to 1 lb of weight. There are cheaper and faster sources of protein. For example, soy…

I'm Jason Green, CEO at Edenworks. And aquaponics evangelist. Here's why we think aquaponics is the best solution to global protein (and vegetable) production. Tilapia are protein producing machines. They convert 1.1-1.3 lbs of feed to 1 lbs of protein in 9 months (some factors like temperature, feed rate at different stages of life, and other things affect this ratio). But here's the real kicker--by providing the ni…

Aquaponics is great from a numbers perspective. But so is Soylent...

Myself, and other conscious humans, conscious of the consciousness in animals, are concerned about quality of life (this is not the same thing as Veganism).

One example of a solution I deem unacceptable is raising rabbits for meat in stacked cages in an urban garage. (This has been advocated numerous times among various alternative food groups and I have read personal accounts of it's practice.)

How are 4^3 IBC tank 'cages' any different?

This has the potential to be the next theoretically-sterile factory farming failure, or a thriving, balanced ecosystem.

Re: The Future of Food on Urban Rooftops

#39

Post by briHass »

jmgreen wrote: post #35
asciimo wrote: post #23

Aquaponics proponents rarely mention that you have to feed the fish. The fish are essentially filters that reduce other matter (mostly other fish) into nitrates. An efficient system would remove these inefficient filters and add nitrates directly to the soil. Yes, you can eat the fish. But it takes 240 days to raise (feed) a tilapia to 1 lb of weight. There are cheaper and faster sources of protein. For example, soy…

I'm Jason Green, CEO at Edenworks. And aquaponics evangelist. Here's why we think aquaponics is the best solution to global protein (and vegetable) production. Tilapia are protein producing machines. They convert 1.1-1.3 lbs of feed to 1 lbs of protein in 9 months (some factors like temperature, feed rate at different stages of life, and other things affect this ratio). But here's the real kicker--by providing the ni…

Excellent reply. The argument that animal protein production is more inefficient than directly eating the plant matter fed to the animal ignores the symbiotic relationship between plants and animals. Our extreme dependence on oil-based energy has tricked us into thinking that agriculture is sustainable without the use of animals. Of course, modern CAFOs are horribly wasteful as well, but that doesn't mean the plant/animal symbiosis isn't vital to the whole process.

All very nicely illustrated by your work.

Re: The Future of Food on Urban Rooftops

#40

Post by fpp »

jmgreen wrote: post #35
asciimo wrote: post #23

Aquaponics proponents rarely mention that you have to feed the fish. The fish are essentially filters that reduce other matter (mostly other fish) into nitrates. An efficient system would remove these inefficient filters and add nitrates directly to the soil. Yes, you can eat the fish. But it takes 240 days to raise (feed) a tilapia to 1 lb of weight. There are cheaper and faster sources of protein. For example, soy…

I'm Jason Green, CEO at Edenworks. And aquaponics evangelist. Here's why we think aquaponics is the best solution to global protein (and vegetable) production. Tilapia are protein producing machines. They convert 1.1-1.3 lbs of feed to 1 lbs of protein in 9 months (some factors like temperature, feed rate at different stages of life, and other things affect this ratio). But here's the real kicker--by providing the ni…

Central London now has residential prices per sq foot from about £1K-£5k+ ($1.5K-$7.6K+) - roof space is often the most expensive (read penthouse) and suitable roofs sparse (at least in London).

How are you planning to find suitable space / scale in such conditions?

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