Backyard Aquaponics
A place to discuss aquaponics

Re: the Growing Power bit - This is what I found http://www.youtube.com/watch?v=jV9CCxdkOng

also found this article (also not by Growing Power) - http://wakeup-world.com/2011/07/14/how- ... n-3-acres/

Growing Power is not actually responsible for this video and the guy that wrote the article only saw the video.

Damon - I took the production level claim by Will Allen with a grain of salt because I'm not sure that Growing Power isn't getting a bad rap here from a video that someone made. I kind of got the impression Will Allen was trying to make a point and was taken out of context.

I looked around Growing Power's website and didn't find anything claiming this production level.

Just for kicks;
1 Acre = 43,500 sq ft we'll just call it 45,000
Growing space claimed in the video for one of the greenhouses = 4500 sq ft so 1/10th acre of growing space in a greenhouse that occupies 2000 square ft.

Number of these greenhouses that could be on an acre = 22.5

Rough weight of a head of lettuce 1.5 to 2.25 lbs we'll call this 1.8 (I got this number off the Internet).

So here goes.... 1Million pounds / 1.8 lbs per lettuce head = 555,555 Heads of lettuce you need to grow.

If you had 10 greenhouses like the ones above, you would have to grow
555,555/45000 sq ft (assuming each head takes 1 sq ft) = 12.34 heads of lettuce per year in each square foot. This just shows that numbers wise it is possible because I'm right around 1/2 acre of land used.

Growing power has 6 greenhouses (based on their headquarters map - http://www.growingpower.org/headquarters.htm) at their headquarters so I doubt they have any chance at hitting 1 million pounds but I didn't count the fish (20,000 lbs /yr ?), the eggs from the chickens ... (probably not significant anyway). If they are doing it, I certainly don't know how, but it is possible. I'm guessing they're around 300,000 lbs/yr based on 27,000 sq ft of greenhouses and 6 growing cycles which is probably low, plus 20,000 lbs of fish fillets.

still those numbers are flawed. you have to consider that a full head of lettuce has a growing diameter of around 8 inches. so you'll only get about 1.3 heads per sqft. using standard logistics as grwoing power is doing, you're only going to get 8 growing cycles per year. which means 10.4 heads of lettuce per year per square foot.. and that's still counting in the stalk and imperfect leaves as weight... and i dont know many people that could consider spotty leaves and the stalk as food... so those shouldnt be counted in as part of the overall weight...

Well actually they're flawed to the low end, what you are saying about the lettuce diameter would actually give me more lettuce because I was basing this on weight with only one head of lettuce per sq ft instead of your 1.3 so the loss in weight is probably going to wind up with us having about the same results. The number of cycles I calculated was for 10 greenhouses, with 20 it would be half that number and could be done.

In my final estimate I also only gave them 6 cycles and didn't factor in that they could pack crops and the cycles could overlap. Anyway, we both know they're not going to make it based just on the greenhouses they have currently but my point was that they could do it in the space they have, with additional greenhouses. Cheers.

This thesis paper gives an analysis of both Growing Power and Sweet Water Organics operations and profitability....

And admissions by both of the operators... that they ARE NOT profitable...

Also gives some financial breakdowns...

http://www.google.com.au/url?sa=t&rct=j ... meoSgfryRw

Thanks Rupe. This is about what I expected. As a non-profit they are actually doing pretty well when you consider what their goals are. Also, if you think about the fact that they are employing people not just on the premesis but people like the fish processor, lawyers, plumbers...