A human being should be able to change a diaper, plan an invasion, butcher a hog, conn a ship, design a building, write a sonnet, balance accounts, build a wall, set a bone, comfort the dying, take orders, give orders, cooperate, act alone, solve equations, analyze a new problem, pitch manure, program a computer, cook a tasty meal, fight efficiently, die gallantly. Specialization is for insects.
-Robert A. Heinlein
Maybe thinking about the towers as having multiple zones migt help.
Not enough sun? What grows in the shade? What grows in the dark?
Can we build the tower as a hollow cylinder?
As a curvy wall?
Can it be a shade structure for other buildings?
Can it use greywater?
Blackwater?
Climate control im such a tower shoud be passive,or at least aimed the needs of plants and animals, not people.
Animals fed from city dwellers waste is perhaps a better use of this space.
Not the waste of individual households as much as that of resturaunts, hospitals,grocery stores, brewerys, food distributers, etc.
Cardboard and pallets into mycilium, leftovers into eggs,blackwater into methane, greywater into evaporative cooling, etc.
The more i think about, it, cities are like human being factory farms.
The sunlight and other resources that a plant needs are already in use, raising humans.
Rats, roaches and other humans already make a living off of the waste of human cities.
We are better off trying to turn the waste from that enterprise into gains than grow plants inside a factory.
Unless we can grow an desirable edible plant off of humanure,in the dark.
That would be awesome.
"Never doubt that a small group of thoughtful, committed citizens can change the world; indeed, it's the only thing that ever has."-Margaret Mead "The only thing worse than being blind, is having sight but no vision."-Helen Keller
Well, not exactly balcony gardens. I think of a balcony as being an open structure--basically a platform, usually with a railing or fence surrounding it on three sides, that is roofed by the balcony on the floor above. What I was thinking was more like a greenhouse on the sunward side of each floor with a rooftop garden in front of the greenhouse on it's sunward side. Each floor would be stepping up to the poleward side and being smaller than the previous floor below it. An outdoor water system could possibly cascade as shallow overflow ponds off each floor onto the next one down at one given spot from off of each roof.Hi Roberto; I think that is probably about right; basically rooftop and balcony gardens on a larger scale.
This (directly to the poleward) side is a great place to conserve water in ponds, and have a green space/park for relaxation/ native plants and trees, as well as domesticated plants which can provide food without much sun. This could also be a place of gray water or black-water processing. All the water that is not being utilized by the plants in the building itself, and any overflow from larger rain events, can be directed to this water feature and forest area. This shaded area, particularly right against or very near the building could be a wood waste generated hot water system (urban areas produce a massive amount of woody waste from tree pruning, and dead tree and branch removals. This might also be a good place for fish and poultry, black soldier fly, mealworms, and worms.A tall building will get more solar radiation overall than its footprint would as flat land (provided there's no other tall buildings around), but that's offset by the light that's not hitting the ground in the shadow of the building.
this is probably true.I personally think they are too inefficient to be part of the future of farming
I agree, but I don't think that artificial lighting is necessary. Also, as the future progresses, the idea of creating a building solely to grow food, seems like it would likely not be cost effective when made of energy intensive concrete and steel. How can it be? That is the biggest argument that I can think of to think that the idea/strategy will eventually peak and crash with no hope of recovery.As someone who personally sees a future ahead where energy isn't nearly as cheap as it is now, I can't see agriculture dependent on artificial lighting going very far.
"Never doubt that a small group of thoughtful, committed citizens can change the world; indeed, it's the only thing that ever has."-Margaret Mead "The only thing worse than being blind, is having sight but no vision."-Helen Keller
I have never met a stranger, I have met some strange ones.
Gilbert Fritz wrote:Some people think that the future of farming will contain high-rise farms; farms in multi-story urban buildings, either custom built or added to existing skyscrapers as a retrofit. I personally think they are too inefficient to be part of the future of farming and simply represent a subsidy dumpster, but I'd be glad to hear other's thoughts on that.
Let's confine this discussion to structures over three stories, and exclude rooftop gardening, which is a different matter.
The main reason I think they are inefficient has to do with lighting. As any gardener knows, even a few feet from a sunny window, plants tend to droop. They need a lot more light then indoor areas allow for. So such a structure would have to be quite thin, or would have to depend on florescent lights. To make these light sustainable, they would have to be run by solar panels; these panels would however take up space somewhere, while losing some energy to transmission and conversion. Thus they would have a larger foot print then the area of plants they would sustain. Such a building would shade other areas, which could have been used for growing; they could not be next to one another, or they would shade one another.
There seem, however, to be other inefficiencies. The taller these buildings get, the harder they are to heat and cool, and the more energy is spend pumping water up into them.
Even as a retrofit, I think the yields are likely to be low without florescent lighting.
They would probably be too expensive for producing staple crops, but would instead probably produce fruits and vegetables. But most cities have enough open land and rooftops to grow all their fruits and veggies; this being so, what purpose would the high rise farm fulfill?
Some say that they could recycle wastes from their own building or other buildings nearby, which is true. But I think this could also be done at ground level, with less expense.
Some also say that they would be great demonstration projects. But if the demonstration project is fundamentally unsound, what does it justify? In that case it would be greenwashing.
Purpose built structures have a huge energy footprint for construction.
Here is an article discussing some of these problems, with hard figures.
https://www.alternet.org/story/146686/why_planting_farms_in_skyscrapers_won%27t_solve_our_food_problems
Can anyone justify these high-rise farms?
To clarify, I'm not skeptical of the value of cities, or of urban agriculture, just of this particular form of urban agriculture.
$10.00 is a donation. $1,000 is an investment, $1,000,000 is a purchase.
A human being should be able to change a diaper, plan an invasion, butcher a hog, conn a ship, design a building, write a sonnet, balance accounts, build a wall, set a bone, comfort the dying, take orders, give orders, cooperate, act alone, solve equations, analyze a new problem, pitch manure, program a computer, cook a tasty meal, fight efficiently, die gallantly. Specialization is for insects.
-Robert A. Heinlein
Gilbert Fritz wrote:they would have to be run by solar panels; these panels would however take up space somewhere, while losing some energy to transmission and conversion. Thus they would have a larger foot print then the area of plants they would sustain.
Photovoltaic efficiency stands at around 20%.
Plant photosynthesis efficiency stands at around 5% max.
Rough figures but they'll do for some speculation...
Thinking maybe a decade or more out. Let's say 100 photons hit a patch of land over a period of time.
If the photons hit a leaf, 5 maximum of them get used to grow the plant, the rest are the wrong frequency eg green light and get reflected or get turned to heat on the leaf surface
If the photons hit a solar panel with 30% efficiency (this is future speculation, remember) and we can then send light from a grow-LED that ONLY gives out photons that will be used by the leaf at a rate that the leaf can use them all, maybe after transformers and resistances and losses etc maybe we can send 20 tuned photons and maybe the plant will successfully use 10 of them.
So, speculation, but reasonable future scenario? We could have a closed structure with PV panels on top and LED inside, getting more growth per square metre than natural daylight?
Whatever you think currently, it is part of the future. Like it or not. Already we grow perfect veg over vats in warehouses. SOld at a perfect price and called organic. YEa, it is like that. If a useless wall of glass and concrete can be used as green spaces or production of food or just oxygen, we are saving the world in one more step. Most of you do not comprehend cities of 50 million,...100 million. I do as I have inhabited them. So yes, if it can produce something for humans I am all for it.
Our space habitats will prove the point. This argument goes the way of sliding doors.
Remember Star Trek? The sliding doors. Oh all these scientists told us it would never happen here on earth. Too much energy, foolish science fiction stories. Yea, just stupid.
I walk past many many automatic sliding doors all day long.
Our megastructures can and will be the greenhouses of the future. The same BTU's can and are being used double purposed. Spaces in normal weather condition in and outside of the megastructures. Can and MUST be utilized to grow and produce products. If not for the air itself and enjoyment, then for food and creation of jobs. Better mental space and to bring the masses back to the reality.
I drive past and do stuff in such structures. If not in them, then on the grounds. Face it kids. 8 billion hungry people will very very soon be 10 billion. The changes in the weather and our dynamic universe,.....well can be our doom or a pleasant future. Embrace it. Permiculture is the cornerstone of this. THINK! It is part of our future. Like it or not.
Gilbert Fritz wrote:I'd still guess that even in this really optimistic scenario, the embodied energy of panels, lights, and structure would eat up any energetic advantage
Gilbert Fritz wrote:A quick bit of looking around the web shows that transporting a head of Romaine lettuce from California to Maine takes around 3000 BTUs of energy. An LED grow light assembly draws 40 watts of power to grow 5 lettuce plants and they take 60 days to produce, during which the lights are on 12 hours a day. The lights are drawing 130 BTUs an hour; this equals 1560 BTUs a day, 93,600 over the 60 days; 18,720 BTUs per plant. And that does not account for the embodied energy of the lights, panels, and wiring, nor the pumping and hydroponics system.
Gilbert Fritz wrote:That's pretty convincing to me. The grow lights could become 6 times more efficient without negating this point.
And a farm right outside of town will need a lot less energy for transportation.
Transportation equation here: https://books.google.com/books?id=QMHdDgkRjDkC&pg=PA217&lpg=PA217&dq=energy+used+to+transport+a+head+of+lettuce+100o+miles&source=bl&ots=zzaRIm8pgB&sig=WO0MkCbjueNlNTzgWEkRFj-3XoU&hl=en&sa=X&ved=0ahUKEwjNqcmzmLDXAhUCxGMKHeYIBxwQ6AEIKDAA#v=onepage&q=energy%20used%20to%20transport%20a%20head%20of%20lettuce%20100o%20miles&f=false
And Light equation here: https://www.linkedin.com/pulse/how-many-led-watts-required-per-square-foot-grow-space-jay-lee
If photosynthesis is currently winning, then why are we (in the loose term of the word "we", I personally am not) building PV "farms" instead of planting trees?
I'm not necessarily disagreeing with your conclusion but I am challenging the idea that all BTUs are equivalent. Perhaps spending 6x the energy on something is worthwhile if the energy comes from a less polluting, renewable source. (Also, not to shatter anyone's conceptions, but I can assure you that even in Winter in Maine the sun does shine a _few_ hours a day
Most likely 3000 BTUs of fossil energy though, right? How many renewable electric refrigerated veggie trucks are cross-crossing the country now? And does the 3000 BTUs figure account for the embodied energy of the trucks, the fuel distribution system, the interstate highway system, etc? What's the bigger investment, some artificial lighting equipment or 46,876 miles of concrete and asphalt
Technology.....translucent greenhouse panels that both admit light--and generate electricity:
http://www.ecosnippets.com/alternative-energy/solar-greenhouses-generate-electricity/
A brief explanation:
Electricity-generating solar greenhouses utilize Wavelength-Selective Photovoltaic Systems (WSPVs),
a novel technology that generates electricity more efficiently and at less cost than traditional photovoltaic
systems. These greenhouses are outfitted with transparent roof panels embedded with a bright magenta
luminescent dye that absorbs light and transfers energy to narrow photovoltaic strips, where electricity is produced.
We might do it in small bits, such as edible potted plants tucked into rarely used corners of a high-rise condo, for the emotional & psychological benefits of greenery, as well as the contribution to the winter heat load of the building. I can grow quite the garden salad for a family in 16 square feet, no matter how it's orientated.Gilbert Fritz wrote:Hi Creighton,
I agree with you that transportation is currently a huge cost. And maybe LED grown produce would use a bit less the 1000 mile produce. And I also agree that retrofits would be more feasible in some ways then new construction for this purpose. However, wouldn't small farms right outside of town have a lower energy use then either 1000 mile produce OR LED grown produce? In other words, if we're doing this because of an energy crunch, investing in lots of LEDs and hydroponics might not be as doable. If we don't have an energy crunch, why do it?
Also, this does not take into account that most current florescent light or LED growing systems are producing tomatoes, lettuce, etc. They wouldn't work very well for staple crops. In an energy crunch, that is what people need; people can survive (though maybe not thrive) without vegetables.
If an energy crunch occurs, wouldn't a more rational response be standard urban farming, with greenhouses and rooftop gardens, while shipping in grains and other staples from nearby farms? My city, Denver, has plenty of room to grow all the vegetables we would need, without a single LED. The staple crops won't be grown in Denver even with LEDs.
I think this is one of the big confusions about this topic; how many calories are going in, and how many calories are going out? Lettuce is mostly water; vitamin water perhaps, but still water. To feed people, we need calories.
Gilbert Fritz wrote:
Yes, but lots of other things besides that lettuce travel over those miles of concrete. Nothing else is grown with those lights.
john mcginnis wrote:"As another poster has already pointed out, a greater energy input than artifical lighting would be water pumping, yet this is something that we already do for towers. This effect would likely result in multi use towers locating the grow operations in the lower floors anyway. "
I think you underestimate the power that a 3 phase 5 or 10hp pump consumes and that is generally the minimum size motor used.
One should understand another aspect. Just because it is technically feasible to DO something does not make it economically feasible. There are hundred things in life doable, but far fewer that are economically so.
But I have an alternate proposal -- move the consumption, aka the people. With the tech we have today a large percentage of the population can work from anywhere. There are small towns across this country that would welcome the population boost. Re-enable the Homestead Act for small towns. Run the numbers and it is probable its a better impact statement; millions of permaculture homesteads across the fruited plain.
Gilbert Fritz wrote:A quick bit of looking around the web shows that transporting a head of Romaine lettuce from California to Maine takes around 3000 BTUs of energy. An LED grow light assembly draws 40 watts of power to grow 5 lettuce plants and they take 60 days to produce, during which the lights are on 12 hours a day. The lights are drawing 130 BTUs an hour; this equals 1560 BTUs a day, 93,600 over the 60 days; 18,720 BTUs per plant. And that does not account for the embodied energy of the lights, panels, and wiring, nor the pumping and hydroponics system.
That's pretty convincing to me. The grow lights could become 6 times more efficient without negating this point.
And a farm right outside of town will need a lot less energy for transportation.
A human being should be able to change a diaper, plan an invasion, butcher a hog, conn a ship, design a building, write a sonnet, balance accounts, build a wall, set a bone, comfort the dying, take orders, give orders, cooperate, act alone, solve equations, analyze a new problem, pitch manure, program a computer, cook a tasty meal, fight efficiently, die gallantly. Specialization is for insects.
-Robert A. Heinlein
Pollution or climate change might force particular populations in various regions to proactively create healthy air for humans to breath, and integration of enclosed gardens might be part of such a strategy, wherein the very fresh garden salads would be a side benefit.
There is an indoor snowskiing resort in Dubai, with 22,500 square meters of well lit and heavily air conditioned floor space. I can imagine such a space being retrofitted towards such an endeavor.
But I have an alternate proposal -- move the consumption, aka the people. With the tech we have today a large percentage of the population can work from anywhere. There are small towns across this country that would welcome the population boost. Re-enable the Homestead Act for small towns. Run the numbers and it is probable its a better impact statement; millions of permaculture homesteads across the fruited plain.
We might do it in small bits, such as edible potted plants tucked into rarely used corners of a high-rise condo, for the emotional & psychological benefits of greenery, as well as the contribution to the winter heat load of the building. I can grow quite the garden salad for a family in 16 square feet, no matter how it's orientated.
Perhaps more rational for Denver, but some cities can't exist without fossil fuel energy anyway, at least not at their current populations, and Denver is likely one of them. Denver Water uses an incredible amount of energy to pump water, both up towards the mile high city, and around it. Los Vegas can't support it's population without pumping water horizontally across many miles, & half the people would be hard pressed to survive a single summer without air conditioning. Half of Toronto would freeze without fossil fuel energy, but only after about 5 years of cutting down all the combustible forests within a few days walk. There simply isn't enough wood growth to heat the buildings that northern cities have now in any sustainable manner. If there is such a short-term energy crunch, a lot of these existing towers won't be "livable" anything similar to how they are currently used anyway. And if you read my post about the ideal building, the grow LED's would only be used half of the time anyway.
A human being should be able to change a diaper, plan an invasion, butcher a hog, conn a ship, design a building, write a sonnet, balance accounts, build a wall, set a bone, comfort the dying, take orders, give orders, cooperate, act alone, solve equations, analyze a new problem, pitch manure, program a computer, cook a tasty meal, fight efficiently, die gallantly. Specialization is for insects.
-Robert A. Heinlein
They worship nothing. They say it's because nothing is worth fighting for. Like this tiny ad:
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