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Vertical farming does not save space

lowtechmagazine.com

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Re: Vertical farming does not save space

#21

Post by gpm »

ravi-delia wrote: post #11
mssundaram wrote: post #8

> the sun provides free energy and the clouds free water This is somewhat tangential to the author's point, however considering the resources from the Earth as free (not the sun) has been a disaster - environmentally, socially and economically. It's like double entry accounting but only entering on one side.

That being said, exactly 0 of the listed examples are actually bad to consider free. If you don't collect rain coming down, it'll just come down anyway.

Farming depleting water tables has been an issue. It's not that it won't come down anyways, but that it won't go wherever it was going next anyways.

Re: Vertical farming does not save space

#22

Post by Groxx »

novembermike wrote: post #2

This ignores nuclear power. It also ignores the fact that you can put solar panels in places that you can't put farms such as the desert.

nuclear, geothermal, loads of other power sources yeah.

I think vertical farming is fairly ridiculous in practice, but this article is fighting against a very obvious strawman.

Re: Vertical farming does not save space

#25

Post by abeppu »

Klwohu wrote: post #10

It doesn't grow many crops, either. I can see it being useful for restricted spaces like balconies or roof top gardens in cities, also because unlike soil gardening the weight is much less even accounting for the hydroponic growing solution. And of course, the gem of the new "industry," the place in Jackson which is a special case, tucked away up in the mountains where it can be hard to get in and out without delays,…

My understanding was part of the reason we get bland veggies in the supermarket is that selection has been for being able to stay good for a longer period and not be damaged during shipping. If vertical farms have less time between harvesting and actual eating, maybe we can pick tastier varietals?

Re: Vertical farming does not save space

#26

Post by villasv »

ravi-delia wrote: post #11
mssundaram wrote: post #8

> the sun provides free energy and the clouds free water This is somewhat tangential to the author's point, however considering the resources from the Earth as free (not the sun) has been a disaster - environmentally, socially and economically. It's like double entry accounting but only entering on one side.

That being said, exactly 0 of the listed examples are actually bad to consider free. If you don't collect rain coming down, it'll just come down anyway.

Interfering with the hydrologic cycle can impact soil quality and may result in bunch of biome effects. It can also have good effects instead of bad effects, though. It really depends on the local dynamics.

Re: Vertical farming does not save space

#27

Post by macspoofing »

Nition wrote: post #17
kibwen wrote: post #7

> 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. This doesn't have to be the case. Plants don't use all the sunlight that hits them, because available light isn't generally the bottleneck in plant growth. Note how most plants are green, whic…

Say a plant needs 1/10th of actual full sun during the day, could you theoretically remove the electricity step entirely but "just" (putting "just" in quotes because I'm sure it wouldn't be easy) having some sort of fancy mirror setup on a 10 storey building to send 1/10th of the sunlight hitting the roof to each floor?

Mirrors take up space too.

Re: Vertical farming does not save space

#28

Post by klodolph »

kibwen wrote: post #7

> 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. This doesn't have to be the case. Plants don't use all the sunlight that hits them, because available light isn't generally the bottleneck in plant growth. Note how most plants are green, whic…

Solar panels can be more efficient, but if your comparison is between “sunlight -> plants” and “sunlight -> solar panels -> electric lights -> plants”, you have to include the actual efficiency of e.g. photovoltaics and LEDs in your calculations.

Photovoltaics these days have something around 15-20% efficiency and LEDs have conversion efficiency around 50-60%. The magenta grow lamps are colored for more efficient use by plants, and you can pack more plants in a smaller space, but at that point you’re trying to offset energy losses on the order of 90%.

Re: Vertical farming does not save space

#29

Post by vondur »

high_byte wrote: post #6
novembermike wrote: post #2

This ignores nuclear power. It also ignores the fact that you can put solar panels in places that you can't put farms such as the desert.

exactly... you can have a farm in the middle of the city and a solar farm in the middle of the desert...

We also have problems with environmentalists who oppose solar in the desert here in California. I don’t think they have been successful judging by the amount of solar installations I’ve seen here.

Re: Vertical farming does not save space

#30

Post by abeppu »

dsr_ wrote: post #20
mssundaram wrote: post #8

> the sun provides free energy and the clouds free water This is somewhat tangential to the author's point, however considering the resources from the Earth as free (not the sun) has been a disaster - environmentally, socially and economically. It's like double entry accounting but only entering on one side.

Most agricultural water costs are from growing crops in areas where there is not enough rainfall: California's Imperial Valley is a desert (3 inches of rain per year) and produces $1 billion of food and cotton each year. Then all the waste runs into the Salton Sea -- another unpaid-for externality.

So, maybe someone here knows the number -- but what would the cost of a loaf of bread be (or what would the multiplicative factor on food costs be) if we restrained ourselves to growing without irrigation?
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