Information specific to the performance of iAVs is scattered throughout the documents on this site. As such, getting a clear picture of what iAVs can do, can be a protracted process.
I’ve assembled this list of performance metrics to assist the process. This list is not exhaustive and will be expanded as I get teh opportunity to read through Mark’s comments on various posts.
- Yields attained in Raleigh, NC indicated that this automobile-sized space could produce 150 kg of fish and 1,100 kg of vegetables per year which assumes a periodic harvest as both the fish and vegetables reach an appropriate size…an average of 3 kg (7 lb) fish and 21 kg (46 lb) vegetables each week). 1
- iAVs has the capacity to produce fish and fresh vegetables sufficient to provide a family with 200 kg of fish and 1,400 kg of vegetables (fruit) per year in a footprint equal to an automobile parking space. 1
- Each 1.0 kg of fish weight gain provided sufficient quantities of all required plant nutrients to sustain 2 tomato plants yielding 5-7 kg of fruit per plant over 3 months.
- Tomato yields exceeded 6.8 kg (15 lb) per plant.
- The rate of water input (replacement of evapotranspiration losses) in the IAVS technique ranges from 1 to 3% of system capacity per day.
- The IAVS technique requires only 11 cubic meters of water per year for each 1.0 cubic meter of system capacity (at a 3% per day rate of loss).
- Depending upon the crop, season, and the biofilter to tank volume ratio, this technique permits from 120 to over 300 crop applications with each unit volume of water.
- Each litre of water employed can produce, in fish and fruit, 0.7 grams of protein,7 kilo-calories food-energy, and most essential vitamins.
- The water efficiency of iAVs is at least 13 times that of UVI raft (DWC) aquaponics – and that doesn’t even account for their failure to factor rainwater into their water use data.
- Including annualized losses for evapotranspiration and incorporation into biomass (food) at 85% of total input and a seepage loss of 6%, each litre of water utilized by the IAVS technique can produce 6 g FW of fish and 17 g DW of vegetables.
- Collectively, tilapia and tomato yields result in 0.7 g DW of protein and 7 Cal. (or 7,000 calories) per litre of water used.
- As the size of the biofilter per fish tank volume is increased, the yield of tomato (for example) decreases from 27 to 19 kg per square meter per crop, but the fish grow 20% faster. This results from a reduction in nutrient availability per plant but an increased filtration capacity (cleaner water) for return to the fish with increasing biofilter size (increasing plant number).
- The sum of the water pumping intervals in the technique developed at NCSU is less than 2 hours per day. The energy demand of this technique is approximately one-twelfth the energy requirement of other recirculating aquaculture techniques.
Fish and Fish Feed
- Each kilogram of feed input to the system will result in the production of approximately 0.75 kg of fish and 6.70 kg of fresh vegetables.
- Fish yields ranged from 50 to 70 kg per cubic meter of water per year (0.41 to 0.57 lb/gal/yr).
- Feed conversion ratios for fish of average market size (0.25 kg) ranged from 1:1.1 to 1: 1.3.
- Some numbers…for example, those relating to the ‘Carpark Model’…may seem at odds with each other. The lower figures relate to low-tech applications…like those typically found in remote villages…where the higher figures apply to medium-tech situations.
- iAVs has never been optimised. The research trials sought to achieve two goals…to prove the concept (the Proto ’86 trial)…and to establish the relationship between the fish tank and sand biofilter volumes (the Ratio 411 Trials). These metrics are simply the outcome of those trials…and provide a performance baseline. The production outcomes were exceeded by Boone Mora and Tim Garrett in the USDA-funded Commercial iAVs Trial…and, it’s reasonable to expect that they will be exceeded by other operators as more is learned about the method.
Aspiring iAVs operators are often confused about how to approach their first build.
I always recommend that newcomers to the method start with something small…a fish tank of 500 to 1000 litres and a sand biofilter/grow bed of 1000 – 2000-litres…which is 3m – 6m by 1metre wide by about 400mm deep. This is your learning prototype.
As you get your head around working with iAVs, you can expend the number of such units to four. This allows you to do side-by-side comparisons of fish species, plant cultivars and operating parameters…a very useful thing indeed.
If you continue to extend your system, this way, you will end up with 16 such units…and your own research facility…and you will quickly establish yourself as the iAVs expert in your area. At that point, you will be harvesting fish on a weekly basis. Not only will you be drawing income on a weekly basis but you will also be able to expand your operation to become an iAVs demonstration centre…where you can even entertain fee-paying students.
Before we reach that point, however, we need to know what your iAVs goals look like. Are you just looking to grow food for your family? Or do you want to sell food into your local market? Or do you want to do that…and run a training business, too?
Regardless of your aspirations, I recommend the modular approach because it allows you to grow commensurate with your knowledge and skills. It also allows you build your operation over time using the production income from each unit to fund those that follow. This self-funding idea applies from your very first iAVs…since you’ll both be taking home clean fresh food to your families…food that you’d have to otherwise lay out money for.
I’ve recently rebuilt the iAVs website…and I’ve moved it.
Just so we’re clear right at the outset…iAVs is – and, in mind, will always remain – the property of Dr Mark R McMurtry. He’s made it available – open source to the world – since it’s conception in the mid- 1980’s…so nothing about the changes that I’ve described should be taken to suggest that there is any shift in ownership or open source availability.
The iAVs site is now part of this one. I’d been trying to rationalise my various websites for some time…partly because of the work involved in maintaining the sites – but also because of the cost. I’ve funded the iAVs website – and all of the work that was done on it – from the outset – and that has become increasingly unsustainable…particularly since I no longer receive a salary.
The other issue is one of focus. Aside from the iAVs.info site, there is an iAVs Facebook page, an iAVs-subforum on my HMFL forum and a couple of other fragments elsewhere. None of them functions as a credible source of iAVs information, so it’s time to pull them together in the interests of greater efficiency.
Anyway, while it’s a work-in-progress, the rebuilt site is already a big improvement over iAVs.info. Finding information is easier – every published article on the site is linked for ease of access – there are several articles that have not been published previously…and the FAQ has been expanded.
It’s taken me over a week of fairly steady effort to get it to this point. The To Do list is still long…my next task is to build a page that will allow us to assist Mark following the fire that left him homeless and destitute.
Anyway, to find the new iAVs section, click on the big green iAVs button right on the front page of this site.
I apologise for the formatting in this post…and I’ll fix it as soon as I can…GD.
Need introduction to the survey – and link. Gary may want to review article and note observations I’ve ‘missed’.
- No claim in the AP survey has been vetted (likely inflated guesses). Zero costs acknowledged. ‘Free’ labor (effort, time).
- One massive outlier claim (outright liar) was removed prior to calculations summarized below.
- Mora/USDA 1992-93 was at v:v 1:1. Mora+ is adjusted to v:v 1:2.4 with same unit area, volume yields.
- Percentile values graphed below, approximated +/- 5% (N=187). https://en.wikipedia.org/wiki/Percentile
- – I.e., Twenty percent of the values of an ordered set will lie at or below the twentieth percentile (P20), and eighty percent of values fall above it.
- Retained in spreadsheet form … with enough numbers to make the average adult primate swoon &/or wretch.
- Percentiles were calculated for (on) area, volume, fish mass and plant mass. Yields and currency value then derived.
- Constant unit values applied throughout, i.e fish $3.30/kg, plant $6.60/kg.
- ‘apples to apples’, ‘claim to claim’, ‘ape to ape’ …
BONUS: Cost to grow tilapia in US (3 feed types, 3 harvest sizes)
What part of this makes ANY ‘cents’? (AKA FKN Insanity)
click image to enlarge
^ Tilapia fillet from $34 to $73 /kg (w/ capex, heating. pumping, labor (time), misc. supplies ALL = $0.00)
actual UPS ground shipping cost from AlliedAqua applied (average of Santa Cruz CA, Atlanta GA, Boston MA and Bozeman MT)
Compare with: today’s prices (July 30, 2016)
- Yellowtail Tuna fillet $37.4/kg (California)
- Albacore Tuna , sushi grade $44/kg (California)
- Maine lobster (1.25 to 1.5 lb size, live) $18.80/kg (Boston)
- Walmart frozen fillet $10.66/4.0 lb ($5.86/kg)
- Fisherman’s Cove, fresh premium fillet $4.99/lb ($11/kg)
- China, frozen $3 to $4.2/kg , $750/MT ($0.75/kg) +shipping
- mytilapia,com : 10-year price range Fresh $3 to 3.5/lb ($6.60 to $7.70/kg) , Frozen $2 to 2.75/lb
- Hmmm IF retail prime is $11, then reg fillet @ $10/kg – 40% -> $6/kg wholesale
- 1 kg fillet @ 35% yield = LW 2.86 kg equivalent
- 1 kg LW = $2.1 /kg (not including processing/ice/delivery costs)
- if process/delivery costs add 30%, then LW ‘value’ = $1.47/kg (used $3.30 in comparison)
click image to enlarge
Put yet another way …
Barely 6 out of 100 in the AP survey claim gross product of $35/m2/yr or more (at F$3.3 and P$6.6/kg). Top range of $40 to $50 m2/yr. What are the costs? AT what costs, risk, effort? APS mean feed cost alone at FCR 1.5 is from 16 to 38% of gross, depending on vendor (5 to 7% at ton volume).
How much better does better need be?
An Open Letter from Mark.
It has sadly come to our recent attention that there are at least a few significant problems having occurred, accrued and continuing to remain unaddressed in India, centered around the impulsive actions and an absence of commitment/responsibility by a certain self-alleged ‘expert’ (actor) known to at least some of you.
We would like to see these admitted “failure stories” resolved to the operators satisfaction in a responsible and timely fashion. We hereby offer – and remain hopeful – that we may provide effective resolutions satisfactory to each impacted party where and as soon as possible.
Therefore, if you (the reader) either are or know of someone who has been the victim of inaccurate, inappropriate and irresponsible ‘advice’ (alleged), then we urgently invite you to contact us directly via the iavs.info website. Please provide us with the full context and nature/extent of your problem(s), as you currently understand them to be and as specifically as you can, such that we may understand your difficulties and help you to correct them to the extent possible such that you may realize your goals.
We do not accept/assume direct responsibility for any errant advice and counsel you may have acted upon in good faith, However, we are sorely aggrieved and harmed in that such situations have admittedly and regrettably occurred – and are apparently continuing to accrue contrary to our specific counsel to desist from increasing problematic implementations and to immediately effect corrective remedies (unacknowledged to date) for the previous harm caused.
We cannot in good conscience allow this most regrettable situation to persist and/or escalate unaddressed. If you are such an aggrieved party, you have our sincere sympathies, and we offer our gratis support to the extent possible as you will allow.
PS… Our offer to assist is not limited to this situation in India. We work toward sustainable food security for impoverished people everywhere! If you are or represent such a person, then please talk to us about what we might do to help you feed people and save water.
A notice for our friends in India. Please excuse this poor translation. It was best that I could manage [after many attempts]. – I sincerely hope that this message reaches those it is directed at soon. – The original English version has been blogged on iavs.info
भारत में हमारे दोस्तों के लिए एक नोटिस कृपया गरीब अनुवाद का बहाना करें यह सबसे अच्छा था कि मैं प्रबंधन कर सकता था / मूल अंग्रेजी संस्करण iavs.info पर ब्लॉग किया गया है
नमस्ते, यह दुख की बात है कि हमारे ध्यान में आ गया है कि भारत में कम से कम कुछ महत्वपूर्ण समस्याओं का विकास, वृद्धि और जारी रहना जारी है, आवेगी कार्रवाई के आसपास केंद्रित है और प्रतिबद्धता / जिम्मेदारी की अनुपस्थिति कम से कम आप में से कुछ के लिए जाना जाता है
हम इन ‘कहानियों की विफलताओं’ को एक जिम्मेदार और समय पर फैशन में हल करना चाहते हैं। हम इसके द्वारा प्रस्ताव देते हैं – और उम्मीद करते हैं कि हम प्रत्येक प्रभावित पार्टी के लिए संतोषजनक समाधान प्रदान कर सकते हैं और जितनी जल्दी हो सके।
इसलिए, यदि आप (पाठक) या तो किसी ऐसे व्यक्ति के बारे में जानते हैं जो गलत, अनुचित और गैर जिम्मेदार वकील (कथित) का शिकार है, तो हम पूछते हैं कि आप सीधे iavs.info वेबसाइट के माध्यम से हमसे संपर्क करें।
कृपया हमें अपनी पूर्ण संदर्भ और प्रकृति / आपकी समस्याओं का विस्तार प्रदान करें, जैसा कि आप वर्तमान में उनको समझते हैं और विशेष रूप से आप जितना कर सकते हैं ।
कि हम आपकी कठिनाइयों को समझ सकते हैं और उन्हें यथासंभव हद तक सही करने में आपकी सहायता कर सकते हैं ताकि आप अपने लक्ष्यों को महसूस कर सकें।
हमारे पास ग़लत सलाह के लिए सीधी जिम्मेदारी नहीं है और सलाहकार ने सद्भावना पर काम किया है, हालांकि, हम गंभीर रूप से पीड़ित हैं और क्षतिग्रस्त हैं कि यह हुआ है और जाहिरा तौर पर समस्याग्रस्त वृद्धि से रोकने के लिए और पिछले नुकसान के लिए सुधारात्मक उपाय (अपरिवर्तित तिथि) को प्रभावित करने के लिए हमारे विशिष्ट विवाद के विपरीत प्रत्यक्ष रूप से जारी हो रहे हैं
हम अच्छे विवेक में इस सबसे अफसोसजनक स्थिति को अस्तित्व या जारी रखने की अनुमति नहीं दे सकते। यदि आप एक घायल पार्टी हैं, तो आप पर हमारी सहानुभूति है, और हम जितनी संभव हो सके उतनी हद तक हमारी नि: शुल्क सहायता की पेशकश करेंगे।
पीएस … हमारी मदद करने की पेशकश भारत में इस स्थिति तक सीमित नहीं है हम हर जगह गरीब लोगों के लिए स्थायी खाद्य सुरक्षा की ओर काम करते हैं! यदि आप इस तरह के एक व्यक्ति हैं या प्रतिनिधित्व करते हैं, तो कृपया हमारे साथ बात करें कि हम लोगों को खाने और पानी बचाने में आपकी सहायता करने के लिए हम क्या कर सकते हैं।
Here in Montana 2017, I could create the following iAVs ‘system’ for under US$7000 (excluding ‘greenhouse’, labor, misc. tools and related supplies):
24 m3 of circular conical-bottom fish tanks with top-quality stainless steel pumps, current state-of-art regenerative blowers (aeration) with top-grade ceramic diffusers, SS fittings etc., and coupled to from 150 to 200 square meters of sand beds. 45 mil EPDM fish/food safe liners throughout. (all equipment Made in US, btw).
0.5 HP, 11,500 litre/hour at 1.5 m head 0.67 HP, 990 l/min @ 1 m depth
That’s between $28 and $35 per square meter (including a 50 m2 tank area) or $2.60 to $3.25 /ft2 with ‘top-shelf’ equipment and materials. Okay, so, maybe add $500 to include some misc. items and delivery costs to my mountain. Would be $1000 less if using in-ground (dug/lined) tanks.
At an average of under $3.00 a square foot, that’s considerably cheaper than any empty Rubbermaid (etc) bin/tub from China-mart. Seriously! How productive could that be for you? What’s the cost:benefit ratio of a flimsy polyethylene bucket on steroids? Where would you plug it in? BTW, un-faced Styrofoam™ (polystyrene) is $1.56/ft2 (alone) at the local Lowe’s (building supply megastore).
At 175 m2 of ‘grow-bed’, planted as single-stem tomato (or equivalent), that’s 700 plants/crop x 3 per year with a minimum of 6 kg/plt, for 12,600 kg/yr plus an expected 1500 to 2000 kg/yr of tilapia. [ 100-120 kg/m3/yr is possible (has been achieved) ]
Before anyone asks, “Why don’t you?” 1) I’m broke, 2) have no GH or growing season, 3) have food and, 4) I’m old, tired, used-up and spit-out.
- Not available in stores.
- Itemized plans sold separately.
- Some assembly required.
- Batteries not included.
- Your smilage may vary.
PS: Ballpark cost for off-grid photovoltaic system to power the above equipment is in the $600 to $1000 range (PV cells, wire/fuse, charge controller and inverter) and without batteries (w/o aeration at night), base supports or installation. For 24-hour aeration (this example) add about $1000 to $1200 (for 500AH@24V for a 10-year +cycle/use life from lead-acid cells. Total overnight load in range of 35-45 AH draw (by latitude and season)… via the cheapest route … here … DIY)
- So, if it cost $1000 for panels etc with 25-yr+ life ($40/yr) plus about $110/yr for batteries. Effective annual cost $150.
- 24 hour load 13,5 kWh w/ 24/7 aeration. 13.5 x 365 ~ 5000 kWh/yr $150 / 5,000 kWh = $0.03/kWh. That’s about one-quarter of what grid electric rate is here. PV really has come WAY down in price over the past few years.
- Running cost (amortized PV) for 2 pumps (1hp @ 2hrs/day) is $0.045/day, $16.43/yr or $0.68 /m3/yr