Low Energy Aquaponics - LEAP

velacreations

BullwinkleII and Dave Donley have described ideas for an ultra low energy system that deserves a test. The system is basically a constant flood, constant height (zero head) throughout.

BullwinkleII's description here: BullwinkleII's system

Dave's from here: DD's system 2010

With a ultra-low or zero head system, we can get away with minimal power. The idea is to keep the water level throughout the FT and the CF GB.

I am proposing a system based on these concepts, with a max energy requirement of 10 watts, which would require a 50-60 watt solar system to run. A solar system of that size can be put together for $400 USD or less.

With an airlift, we should be able to get 200 lph per watt at zero or ultra-low head (100mm or less). Power heads might be appropriate for this system, too.

I have a few 800 l HDPE tanks that would work for FT. For GB, I'm thinking a kidding pool or some blue barrels. With 800 l, we need around 1000 lph. We should be able to do that with 5-10 watts of airlift or powerhead. We should be able to stock 40 fish, yielding about 20 kg (hopefully). Tilapia might be a good fish choice.

I am completely off grid here in Northern Mexico, and a system like this would enable us to have fish here. I know of a lot of people who could benefit from something like this.

For now, I could run this system by charging and swapping batteries from my house system. This would enable me to test the system before investing in a solar setup.

So, I need comments, tips, suggestions, ideas, and advice to get this going. I hope to be able to put this together in the next few months, but I want to start the discussion now to get all the ideas on the table.

Jimbo Rollins

LETCH? Low Energy Total Constant Height?
Just a guess-please correct me.
I'm planning something like this with 2 IBC's-cleaning them out today.

http://www.backyardaquaponics.com/forum/viewtopic.php?f=18&t=11703&sid=f4474a170bbb26b94b6e0177426391ee

Dave Donley · Screen shot 2012-01-29 at 2.53.15 AM.png [ 22.05 KiB | Viewed 24423 times ]

Hey that's great Vela, hope it comes together and we get some good data from it. I'd love to see you try something along those lines.

Here's a copy of the AP insomnia picture I did for SnowT's air lift thread. Would be interesting to figure out optimal locations and numbers of holes for the sides of the bed.

The terms I have rattling in my brain are "diffusion beds" because the water is introduced to the bed under pressure and allowed to leak out kind of like diffusing, and "sideways" systems, because the pumping is not really moving things up and down but only sideways.

Edit: BTW LEAP is kind of a cool acronym!

velacreations

Jimbo Rollins wrote:

LETCH? Low Energy Total Constant Height?
Just a guess-please correct me.
I'm planning something like this with 2 IBC's-cleaning them out today.

http://www.backyardaquaponics.com/forum/viewtopic.php?f=18&t=11703

Yeah, LETCH is what BW was calling it. I am not too worried about the name, but more of how it will function.

You're IBC system looks awesome. Feel free to post your diagram to this thread, and let us know how the experiment turns out!

velacreations

Dave Donley wrote:

Hey that's great Vela, hope it comes together and we get some good data from it. I'd love to see you try something along those lines.

Here's a copy of the AP insomnia picture I did for SnowT's air lift thread. Would be interesting to figure out optimal locations and numbers of holes for the sides of the bed.

The terms I have rattling in my brain are "diffusion beds" because the water is introduced to the bed under pressure and allowed to leak out kind of like diffusing, and "sideways" systems, because the pumping is not really moving things up and down but only sideways.

Edit: BTW LEAP is kind of a cool acronym!

Yeah, I love the look of that image. very elegant.

I'll be using what I have on hand, optimizing for the lowest energy use possible.

Any suggestions or ideas on how to make it work well are greatly appreciated!

This is really the first AP system that looks like it might work for my situation. I have been following AP stuff for several years, but until now, I haven't come across anything that was feasible on a small power system. This concept could prove to be very revolutionary in terms of energy.

velacreations

here are some airlift links, for anyone interested in low head, low energy stuff:
here are some documents for airlifts:
http://www.northidahokoikeepers.com/sit ... tation.pdf
http://www.alabdiffusers.com/Airlift.htm
http://www.ca.uky.edu/wkrec/AirliftPumps.pdf
http://www.airliftpump.com/airlift_basi ... lation.xls

also, check out http://www.koiphen.com/forums/, they have lots of airlifts in operation.

At 100mm head or less, you should be able to achieve at least 200 lph per watt (or better) with an airlift.

Efficient water pumps can provide 40-60 lph per watt, so you can see that at low heads (300mm or less), airlifts are significantly more energy efficient.

missionaryman

Hey guys

How much air is needed for this concept to work. Think you could use a small air bubbler... on a smaller scale of course?

velacreations

it depends on a lot of things, but we're trying to get 1000 lph minimum. From what I've read, that should require about 7-10 lpm air supply at about 2 psi. I think most small air pumps could do this, but I'm no expert.

velacreations

powerheads might be another viable option, as BW has pointed out. They key with them would be to mount the powerhead near the surface to get enough surface turbulence for adequate aeration. BW had an 8 watt powerhead that claimed 3,000 lph, which would be great!

velacreations

here's a chart with some various efficient air pumps. I don't know if any of these would work, their power consumption is higher than what we want, but it is useful info, nonetheless:
http://www.christianjamesphoto.com/airpumps.html

Stuart Chignell

Now I remember why submergence was such a key. Sense airlifts work on decreasing the density in the lift the deeper they are the more surrounding weight of water to do the lifting.

velacreations

yeah, the deeper, the better. You want a minimum ratio of 4:1, 4 units of submergence to one unit of lift. If you want a really efficient design, submerge the airlift 2m, and then set the head at about 100mm. The efficiency should go really high on a setup like that.

velacreations

here's a powerhead comparison:
http://www.wetwebmedia.com/ca/volume_3/ ... d_comp.htm

Some of these barely beat out regular pumps on efficiency. Looks like the Tunze line is the best. I saw a Tunze Turbelle NanoStream Pump 6015 that claimed 1800 lph @ 3.5 watts.

missionaryman

This is deffinately a concept that i am going to put much effort into. I am teaching Aquaponics at a refugee camp in a couple weeks where low energy concepts are a must. Thanks guys. any more links or threads you may know of to help me out???

MM

velacreations

another powerhead comparison:
http://reefkeeping.com/issues/2003-09/nftt/index.php

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