this post was submitted on 13 Jul 2023
25 points (96.3% liked)

Solarpunk Farming

1126 readers
36 users here now

Farm all the things!

Also see:

founded 2 years ago
MODERATORS
 

cross-posted from: https://lemmy.world/post/1443397

With office usage hovering near 50 percent of pre-pandemic levels, cities are putting the underutilized space to new use growing food

top 5 comments
sorted by: hot top controversial new old
[–] [email protected] 6 points 1 year ago* (last edited 1 year ago) (1 children)

When executed correctly, vertical farming can yield as much produce as traditional farming methods in urban areas and smaller spaces. Additionally, vertical farmers gain the added benefit of consistent, year-round production without the uncertainties of climate or pests, all while utilizing 90 percent less energy and 98 percent less water than a traditional farm. Although it can’t be a replacement for more traditional methods, vertical farming provides fresh produce in areas that have little food production or access to healthy foods.

... 90% less energy? I'd love to see a citation on how on earth that is possible. This is a puff piece taken entirely from a few companies, taking their claims as truth. I'm not saying vertical farms don't have their place, but how can they use 90% less energy while having to operate grow lights.

Vertical farms seem to have a lot of hype, and consequently I've seen mounting criticism. Lowtech magazine had a piece about how a solar paneled vertical farm actually uses more space than a regular one, if you account for solar panels, and are only cost effective because of fossil fuels.

edit: the link earlier in that sentence goes to a press release from IDTechEx, which does "independent market research." These are marketing agencies who put out "reports" as self-marketing, hoping to be hired by companies to make more rosy reports on how great their industries are. It's capitalist cargo-cult science, but even they seem to outright contradict the smithsonian magazine claim:

On a larger scale, vertical farms may prove more profitable in different geographical regions. Vertical farms can reduce water usage significantly over conventional agriculture, and the high degree of control over the growing environment allows them to grow crops in extreme climates – where such crops may not otherwise be able to grow. In return, vertical farms demand more energy to carry out growing operations [emphasis added]. To maximize their potential, vertical farms would ideally be located in regions of water scarcity, such as Sub-Saharan Africa and the Middle East, or in areas with extreme climates, such as in Scandinavian countries, where the low amounts of sunlight and high costs of regulating greenhouse environments single out vertical farms as an optimal solution. The amount of agricultural land available is also an important factor – regions looking to increase food security and reduce reliance on imports while facing challenges in acquiring sufficient agricultural land would find vertical farms to be ideal. A particularly prominent example of such a country is Singapore, which has demonstrated much interest in vertical farming over the last few years.

[V]ertical farms are very energy intensive [emphasis added], and it is important to ensure the facilities chosen can support these energy loads. In addition, the ergonomics of the facility is also important; should the layout not be given proper consideration, this can impede workers and decrease worker efficiency. As labor costs are typically among the largest sources of expenditure for a vertical farm, improving labor efficiency to reduce these costs is of paramount importance.

I call shenanigans on the energy usage claim. There's no way it's possible.

[–] [email protected] 1 points 1 year ago* (last edited 1 year ago) (1 children)

Tractors use a lot more energy than LEDs while running. But you can operate LEDs indefinitely. So the source of the energy would be important.

[–] [email protected] 2 points 1 year ago* (last edited 1 year ago)

No, it's not even close. According to that link I posted, growing 1m2 of wheat costs 2,577 kilowatt-hours of electricity. 1 gallon of gasoline has 33.7 kilowatt-hours. That single 1m2 of wheat used the energy equivalent of 76 gallons of gasoline, and that is for a single pound of flour. LEDs are efficient, but vertical farms require extraordinary amounts of them to be on 24/7, whereas a single farm can use one tractor.

You can just look up how much fuel farms use. The general rule of thumb for cereal crops is 2 gallons per acre per season, and that includes planting, the maintenance, and the harvesting. Multiple that out, and you get that vertical farms use 157,827x more energy. That is 5 orders of magnitude. To put that in perspective, the distance across the US vs the distance to the moon is only two orders magnitude difference.

edit: In case you don't believe lowtech magazine, here's another source. https://ifarm.fi/blog/2020/12/how-much-electricity-does-a-vertical-farm-consume

It claims that vertical farms use 57.35 kWh per square meter per month for the lowest possible energy consumption crop, lettuce. This is an astounding amount of energy. That is 1.5 gallons of gasoline per month per square meter for lettuce. If you want to grow strawberries, it almost triples. That still comes out to 3-4 orders of magnitude, depending on the crop.

[–] [email protected] 2 points 1 year ago

Finally, an efficient and productive use for office buildings.

[–] [email protected] 1 points 1 year ago

As they should be. Good way to buy local and cut down on pesticide and water use.

load more comments
view more: next ›