“Vertical farms have nailed leafy greens.”

“Vertical farms have nailed leafy greens.”(wired.co.uk)

3 points by erdle 8 years ago | 3 comments

erdle 8 years ago |

How does the math work out on indoor farms?

This particular article gets into numbers around water, but also mentions growing fruit such as strawberries which are 92% water. But they claim they can grow 350x per acre what outdoor can do and with 1% the water...

grown indoor or outside... the water in a pound of strawberries is a constant...

currently in CA, an acre of strawberries yields ~60,000 lbs of strawberries per year... 350x that is... 21,000,000 lbs of strawberries per ace...

so per acre, it would require a min of 231,377 gallons just for the fruit alone

currently it takes about 12 gallons of water in CA to yield 1lbs of strawberries, but that's the entire plant, fruit and all... 1 acre uses 720,000 gallons per year...

...to get 21m lbs of strawberries, you need 252m gallons of water

1% of that is 2.5m gallons

2.5m gallons weighs 20,850,000 lbs

21m lbs of strawberries is really just 19,320,000 lbs of water

so 92% of the water consumed in total goes to fruit...

which means they have strawberry plants that require virtually no water

and then you have the inputs... if it costs $40/lb right now... a test acre of strawberries alone... would cost $840,000,000 at their current rate...

and then their best case scenario mentioned would be $1 per pound so... $21m/acre

it currently costs $23,000 per acre in CA to grow 60,000 lbs....

so 350x that... and you're still at $8m an acre

so in their best case scenario... their inputs are still 2.6x today's current costs... startup costs are billions... and water numbers are off...

it would be interesting to see what they're telling investors and what is actually possible given that inputs like water are a constant no matter how a fruit is grown on a per pound basis

dig247 8 years ago | |

I feel a bulk of it is just marketing hype. Certain things don't scale well, but they sure sound good and shine bright. Snow flakes and bad math, Let's IPO and pass it on to retail investors.

Bringing production closer to the point of consumption/end user does indeed make sense. All the inputs in an indoor growing environment definitely twist things up once you really do the math. Vertical outdoor would make more sense. As soon as you incorporate HVAC, lighting, growing media, hydro set up, rent in urban areas, cost of human labor, nutrients, water purification/recycling, genetics, dehumidification if required, pesticides, air filtration, opex, and on it goes...it becomes rather messy and impractical in the short term.

ethiclub 8 years ago | |

I suppose (thinking on a more macro level than a single org's p&l) there are also opportunity costs to consider.

Arable land that would otherwise be used for (leafy greens in this example) can be repurposed for other crops, preventing further deforestation et al.

Or perhaps this land would be suitable for rewilding - Or, given that farms are likely situated at fairly convenient transit points (which may align with power transfer needs), other industries such as energy could essentially rezone these areas into solar fields.