Sciencemadness Discussion Board - aga and the Spud Cell

aga and the Spud Cell

aga - 13-4-2016 at 11:33

Coolio huh ?

Yep, this afternoon i built a Potato Cell, which is an ebb-and-flow type of hydroponic growing system, using no soil or artificial growing medium.

The materials were two old pallets, two broken plastic fruit crates, a submersible pump, some pipe, polythene sheeting and opaque black plastic sheeting (used in agriculture to keep weeds down). There is also some bamboo and rope, but they turned out to be pointless.

It is now running on solar power, controlled by a 12v timer from ebay. Here's some drawings of how it works :-

The idea is simply to have All of the water and plant nutrients in the Outer/Lower tank, then periodically flood the Inner/Upper, plant-containing tank with that solution, feeding the plant roots with everything required.

A period of No water in the upper tank supplies plenty of oxygen to the roots, which seems to be best practice.

The really cool part is the very simple syphon (=a bit of tubing).

This simple device means just 1 pump to control Filling AND Emptying !

The Upper/Inner cell can be held in State 2 (where the plant gets water/nutrients) for as long as you like simply by timing it so the water does not rise to the level of the top of the syphon.

As soon as the water hits that level, the syphon automatically empties all the water into the Outer/Lower tank, re-cycling the energy used by the pump to do the filling.

The idea came when doing a soxhlet extraction a couple of days ago. Previously a second pump or a motorised valve were considered for controlling the emptying process.

The black plastic sheet is just to keep light off the new potatoes, because they go green unless they are in darkness.

The only reason there is an Inner and Outer tank instead of a perfect Upper and Lower tank is that the Inner tank was made first, then found to have a few small leaks. The simplest solution (due to a shortage of plastic sheet) was to put the Lower tank entrely around the Inner tank to catch the drips, making it into the Outer tank.

Some stats :-
Outer tank : 98 litres
Inner tank: 82 litres
Fill time: 10 mins
Empty time: 15 mins
Plants: 7
Cycles: 3 per day

Total Cost: ~$30
(or $863,928 in case NASA want to use the blueprints)

[Edited on 13-4-2016 by aga]

Daffodile - 13-4-2016 at 12:02

That's pretty cool. I've got a grow project for plants as well. The plants I'm growing are, uh I don't know how to spell it right but I think its ... pot?

blogfast25 - 13-4-2016 at 12:06

Nice!

And no calculus required, unless you want to predict the emptying time of the inner tank.

aga - 13-4-2016 at 12:07

Quote: Originally posted by Daffodile

That's pretty cool. I've got a grow project for plants as well. The plants I'm growing are, uh I don't know how to spell it right but I think its ... pot?

LOL.

That species does best in a Bento bucket (aka Dutch Bucket).

Tuberous vegetables need stuff like this.

aga - 13-4-2016 at 12:11

Quote: Originally posted by blogfast25

Nice!

And no calculus required, unless you want to predict the emptying time of the inner tank.

Now we're talking !

It would be a Tribute to these recycled crates to have a Formula written on the side.

I think all the relevant data is there, so Let's Derive, Integrate and Comment !

hissingnoise - 13-4-2016 at 12:50

Quote:

The plants I'm growing are, uh I don't know how to spell it right but I think its ... pot?

Ociffer, arrest that flower ─ no rush maaan, finish the bowl and then take him in . . .

Erm, I'm halfway through my first fattie of the night . . . (cough!)

Metacelsus - 13-4-2016 at 13:28

After seeing the title, I thought you had made a potato battery.

Quote: Originally posted by aga

Total Cost: ~$30
(or $863,928 in case NASA want to use the blueprints)

NASA doesn't need the blueprints -- they have Mark Watney to design all potato technology.

aga - 13-4-2016 at 13:45

Hmm.

The Lower tank is actually large enough to contain a chopped-up corpse, so perhaps i can drop all the complicated calculations of chemicals to add to the water and go 100% organic instead.

Funny thing is that i have been accused of being a non-Eco freak by a local farmer who regularly doses his crops with some stuff that neither i nor he know the contents of.

He lobs horse shit everywhere then liberally applies these unknown chemicals all over the ground, yet in his mind he's Cool and Eco.

I apply known chemicals in known quantities (all IOC, nothing else) in a controlled environment, yet i'm the planet-violator.

Then again, i chose not to marry my sister's sister, who is technically also a Cousin, so what could i possibly know about anything.

blogfast25 - 13-4-2016 at 13:52

Quote: Originally posted by aga

I think all the relevant data is there, so Let's Derive, Integrate and Comment !

I'll include the syphon emptying a tank as an example of a Real World bit of calculus (in that thread).

aga - 13-4-2016 at 13:58

Quote: Originally posted by blogfast25

I'll include the syphon emptying a tank as an example of a Real World bit of calculus (in that thread).

It would be an Honour to explore that Math, Sir.

[Edited on 13-4-2016 by aga]

arkoma - 13-4-2016 at 14:45

Pretty damn good brain storm, I see the logical path from the soxhlet..............

blogfast25 - 13-4-2016 at 18:34

Quote: Originally posted by aga

It would be an Honour to explore that Math, Sir.

It'll be my pleasure but you'll have to show the spuds at some point. I have about 1/128 Irish in me^(*).

(*) Completely made up, that part.

[Edited on 14-4-2016 by blogfast25]