Harry Ako and PingSun Leung
Depts. of Molecular Biosciences and
Bioengineering and Natural Resource and
Environmental Management
College of Tropical Agriculture and Human
Resources
University of Hawaii at Manoa
•We generated a simple economic model that was fun to play with and I
came to some interesting projections.
•We gathered information from farmers which was very interesting to me.
•I therefore told Clyde, why don’t we have a workshop? A little out of
hand.
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We thought that aquaponics might be
good for island ecosystems because it is 6
times more productive per unit area of
land, uses on 2% of the water as
traditional agriculture and releases no
effluent into the environment . It is nonpolluting.
We just got back from Samoa.
E-mail hako@hawaii.edu for how to
manual.
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We worked on a very simple system. Plywood sheet
with walls, tub for fish, air pump, bucket. Shown.
Both the Ako approach and the Fox/Tamaru
approach are highly technical
What we did: Economics determined by
materials cost to build an 8 plywood system and
cost of operations
This report is based on real numbers and very modest
extrapolation. Recorded the price of the wood, every brick,
PVC pipe etc. Labor not accounted for.
Items
Lettuce
Life
traya
1 plywood
10
$130
Shade structure
10
$60
Fish tank
10
$80
Air pump
5
$80
Laborb
$0?
Total
$350
aincludes
•Cost of each component of
each item.
•Lifetime of each item.
•Costs 3.5 X higher for pre-made
systems or another kind of system
wood, screws, plastic, polystyrene sheets
bbuild yourself; this is not as good an assumption
when the system is large.
Items
Life 1
12
plywood plywood=
racewaya
5 raceways
Lettuce tray
10
$130
$1,560
$7,800
Shade structure
10
$60
$720
$3,600
Fish tankb
10
$80
$600
$2,600
Air pumpc
5
$80
$220
$1,100
Water pump
5
$310
$1,550
Refrigerators (2)d
10
$1,100
Delivery vane
10
$20,000
Total
$350
$3,410
$35,110
Annualized cost
$43
$332
$6,260
a4
Annualized costs
are costs/lifetime
in years
feet wide, 100 feet long; see figure
b use larger tanks
cuse blower for larger operation
dvs $8000, chosen for energy conservation reasons ($90/yr vs $4300/yr)
edoes a farm this size need a van?
•Build yourself
1 plywood
12 plywood=
raceway
5 raceways
Fingerlingsa
$15
$180
$900
Feed
$27
$324
$1,620
Electricityb
$66
$788
$3,942
$0.56
$6.69
$34
Suppliesc
$20
$239
$1,200
Interest
$35
$341
$1,815
Labord
owner
owner
owner
$74
$434
$1,774
$9,045
Water
Lease rent
Total variable
costs
amost
$148
of us grow our own; costs are nursery costs
bat $0.30/kwh; cOasis cubes mostly; dfor the 1 plywood
or backyard system, approx. 2 hr/wk; for the 1
raceway 5-10 hr/wk; 5 raceway, approx 20 hr/wk
1
12
plywood plywood =
raceway
Lettucea 211 (7.4 )
tilapiab
43 (0.83)
5 raceway
2,534 (89)
12,672 (443)
515 (10)
2,574 (50)
Farmers can be more or less productive
These values predict sizes of niche markets that can
be serviced.
a
from mediocre season like Spring; 250 g/head
bmarket size= l 1b
http://img.alibaba.com/photo/11697156/Tilapia_Fillet_Light_Skinned_CO_Treated.jpg
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Choose the production volume you would like
to do.
This in most cases determines the markets you
can compete in and the prices you can get.
A common error is to produce without
thinking about the market.
1
12 plywood = 5 raceway
plywood raceway
Lettucea 211 (7.4 )
43 (0.83)
tilapiab
2,534 (89)
12,672 (443)
515 (10)
2,574 (50)
•Our production numbers say 7.4 heads of lettuce or
other vegetable per week. Maybe 1 fish/wk. Is this
enough for a family?
•You save by not having to go to the supermarket.
Prices, retail, $5.60/lb for lettuce and $9/lb for live fish.
Annual capital
cost
Annual variable
cost
$
43
$
148
Value of lettuce
$
1,183
Value of fish
$
386
Net profit
$
1,378
Thus, based on the model a backyarder
could save about $1,400 a year at the
grocery store. Pays for this system in a
few months (there are more expensive
systems). Or just like the idea of being
self-sufficient?
1
12 plywood = 5 raceway
plywood raceway
Lettucea 211 (7.4 )
tilapiab
43 (0.83)
2,534 (89)
12,672 (443)
515 (10)
2,574 (50)
•Our production numbers say 44 heads of lettuce a week. Enough for
farmers’ market? Five fish a week.
•Prices, retail, $5.60/lb for lettuce and $9/lb for live fish.
•Will have to rent stall, go to farmers’ market, deal with food safety
issues etc.
Annual capital
cost
Annual variable
cost
$166
$887
Value of lettuce
$7,096
Value of fish
$2,317
Net profit
$8,360
Thus, based on the model a farmers’
market person could earn about $8,000
a year. Decide for yourself whether it is
worth it.
Now Janet and her husband, Ray,
have cultivated a small business —
with a big customer following —
selling lettuce and other greens at
Manoa Marketplace’s open-air
market…. The bags range from $2
to $6, depending on the size….
1
12 plywood = 5 raceway
plywood raceway
Lettucea 211 (7.4 )
tilapiab
43 (0.83)
2,534 (89)
12,672 (443)
515 (10)
2,574 (50)
•Our production numbers say 443 heads of lettuce per week. Is this
enough for small specialty store? And 50 fish/week.
•Prices they say are $3/lb for lettuce and $6/lb for live fish.
•Capital costs for pre-made or other systems are 3-4 times higher
than ours.
Annual capital
cost
Annual variable
cost
Value of lettuce
$2,080
$9,045
Thus, based on the model a small farmer
could earn $42,000 a year if all goes
well.
$38,016
Value of fish
$15,444
Net profit
$42,335
Premature conclusion. You can make
money but won’t become a millionaire.
1
12 plywood = 5 raceway
plywood raceway
Lettucea 211 (7.4 )
tilapiab
43 (0.83)
2,534 (89)
12,672 (443)
515 (10)
2,574 (50)
•Our production numbers say 506 heads of lettuce per day. Is this
enough for a discount supermarket? The 400 fish a week would
probably overwhelm the live fish market.
•Prices might be $2.25/lb for lettuce and $6/lb for live fish (though this
high price may become unlikely).
Annual capital
cost
Annual variable
cost
$50,080
$72,357
$228,096
Value of lettuce
Value of fish
$123,552
Net profit
$229,211
Cost of labor would have to come out of
profit. We estimate 4-6 workers. The
farmer would be profitable if he or she
did everything right.
1
12 plywood = 5 raceway
plywood raceway
Lettucea 211 (7.4 )
tilapiab
43 (0.83)
2,534 (89)
12,672 (443)
515 (10)
2,574 (50)
•Our production numbers say 506 heads of lettuce per day. Is this
enough for a discount supermarket? The 400 fish a week would
probably overwhelm the live fish market.
•Prices might be $1.25/lb for lettuce and $6/lb for live fish (though this
high price may become unlikely).
Annual capital
cost
Annual variable
cost
$50,080
$72,357
$126,720
Value of lettuce
Value of fish
$123,552
Net profit
$127,835
Cost of labor would have to come out of
profit. We estimate 4-6 workers. Six
workers would make the business
unprofitable.
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We developed a preliminary economic model
Working with the model was fun
 It predicted profitability if there is technical
excellence and imaginative niche marketing
 We can comfortably recommend aquaponics on
these bases. A person can make money but will not
become a millionaire
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I enjoyed learning a little economics
I especially enjoyed learning from the farmers
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CTSA seed money grant
Western Sustainable Agriculture Research and
Education
CTSA Pacific Island grant