Fuel cell that harvests electrons from the bacteria in mud! And ELECTRons mean ELECTRicity....you get me?

The cell also makes a great habitat for a beta fish... The bacteria decompose the fish poop adding to the cell's fuel and keeping the water clean!

Step 1: Get Some MUCK!

"MUCK" is actually the correct term for soil from Wetlands .... I LOVE WETLANDS!

Muck has all kinds of awesome bacteria, one of which is Geobacter, it produces electrons as part of its cellular digestion!
Voltage up to 725mV and counting!
<p>Increasing surface area of cathode may help. a metal plate with one side touches the water surface and the other expose to air.</p>
<p>I was doing some research on the subject and this is what I came across: </p><p>The first step requires the removal of electrons from some source of organic matter (oxidation), and the second step consists of giving those electrons to something that will accept them (reduction), such as oxygen or nitrate</p><p>So I know that the first step (oxidation) comes from the muck. Yet it does not seem that reduction is visible in this fuel cell. Could someone elaborate. Because I can't find the second step anywhere. Thanks!</p><p>My source: http://www.research.psu.edu/capabilities/documents/MFC_QandA.pdf</p>
<p>I'm building this for my science fair assignment but my teacher wants to know what is the size of the PEM, because it looks fairly large in the picture but, if I am correct, judging by the measurements to make the Proton Exchange Membrane it isn't that big. Am I correct? @drdan152</p>
Hey! Cool! Your right it's not that big..... I just used a &quot;Petri dish&quot; filled with salt and gelatin...... Jello with extra salt added should work ok too! Really the principal is that there should be a layer of muck then a PEM on top of that then water! So how ever you accomplish that...... It's up to you!
What has been the most efficient anode design? Screen mesh? Wires to the cloth? If so how? Flat? Rolled! Max surface area?
<p>flat and max surface area!!!</p>
<p>Graphite is better as electrode.</p>
<p>Graphite is better as electrode.</p>
Thanks for the great instructions! I'm doing this for my science fair project, and the voltage from my first attempt is decreasing daily rather than increasing. Any suggestions?
<p>its because bacteria need food for their life cycle, try adding glucose or other sugars with it.</p>
Um I'm confused with the proton exchange membrane. Do you have to freeze it?
<p>yes you do have to freeze (solidify) it.</p>
<p>In a anerobic enviroment it started reducing the bacteria and clogged the probe voltage dropped to 560 mV.</p>
<p>Here is a small portable bioreactor made from a broth of 1 million cultures of lactobacilus retuni which converts glucose into lactic acid, citric acid, succinic acid and other acids. The ph drops and this increases the acidity. The probes are copper and stainless steel. The voltage measured was 706 mA.</p>
<p>Were you able to eventually power an led and design the charge pump circuit. If so could you send pictures and instructions on how you did so. I'm designing one for a science project and my goal is to try and power a led light. </p>
My son just made one today for science project. Its been a steady 950mV for the first 6 hours. Maybe we will get over a volt??? Cool project.
Wow! It looks great! Nice job! Glad to hear people have fun making the projects!
<p>Science?</p><p>I see cruelty to animals!</p><p>Except this is a plastic fish but then still it is idiotic to publish this way!</p>
<p>actually its animal's shit used to harness volts. not animals or their meat.</p>
<p>great project could you bring it to 3 volts an power a led</p>
<p>What do you mean by &quot;cover the anode from top and bottom&quot;.</p>
Hey! I was looking at this and plan to wire up a bunch of them for higher voltages, but how does this beta fish survive? What does it feed off of? <br> <br>Thanks for your help!
<p>The cell is a totally harmless (although small) aquarium.....totally PH balanced and the bacteria has nitrogen fixing bacteria that help keep the water clean! Just feed the fish like you normally would and water changes etc.</p>
Beta pellets..... Duh.. <br>What else?
What step does the Beta come in?
<p>last step!</p>
How well would this work on a major aquarium scale (Georgia or Tennessee aquarium). You said in a comment that the more surface area you have the better it works and there are a ton of fish to poo all over the bacteria. This could help power the aquarium and clean the water. If someone was building a new aquarium this could be put in but how many volts and watts does it produce?
<p>I have a feeling its exponential...imagine all the power we could harness from wetlands! Wetlands clean our water, prevent flooding, provide habitat for wildlife and in the future may be electrical powerplants as well...hey powerPLANTs haha get it?</p>
I am hoping to do this as my project in school. And i have a question, can we do this large-scale?
Hey! The best way to make it large scale is to make a bunch and wire them in series! Lemme know if u need anymore help. <br>
Has anyone successfully done this? I am reading it doesn't work without using capacitors to catch the voltage.
<p>It works! However you need a charge pump circuit with capacitors like you said if you want to power an LED....this is just a demo using a multimeter to show how much voltage little bacteria can make...which is cool.</p>
yeah thats a good idea!
hey, how did the poop go to the muck? isn't the PEM is in between them?
<p>Just dissolved into the solution!</p>
<p>We can't keep our PEM from dissolving as soon as we put it in the cell? We used 2.5% unflavored KNOX gelatin and 2.0M NaCl for the PEM. The recipe calls for about 6.5M NaCl, but when we tried that concentration, the gelatin completely salted out of solution.</p>
<p>Try agar agar flakes from the natural or Asian store...it makes really good solid gelly!</p>
That is in no way an ideal environment for a betta fish. It's absolute bullsh*t when people say they don't need much space. Mine have at least a 5gallon tank each. They are intelligent, inquisitive and playful fish and you deserve a place in hell for keeping them in such sh*tty conditions. Animal abuser!!
have you video for this article?? coz i need detail process
I put fish oil and added light to my beaker and it momentarily increased the voltage!
Sooo cool! Keep up the experiments! I noticed too that if u take a straw and blow bubbles into the water it increases voltage... Prob due to more O2 available for the &quot;redox&quot; reaction
wow i wonder if you have enough milliamps to power a led to light up that fishy!
Thank you so much for your fast response!
No problem! Let me know if you need any more help! Can't wait to see your finished fuel cell! I have all the parts for a charge pump circuit so hopefully i can get it up and running 3v for a clock or something...ill keep it updated!
Is there a good substitute to window screen? Would any easily bendable metal be okay?
Actually I discovered a way way WAY better Anode/Cathode design that just uses the char cloth and the wire with insulation stripped off...I'm posting the updated info as we speak, the voltage went from 145mV to 585mV just by this simple change!
I wonder whats the wattage is of those setups? A few milliwatts at max i think. However, that would be more than enough for sensor-networks to run on. <br> <br>Also as a sidenode: be sure you check also &quot;Energy harvester&quot;-Chips from Linear technologies like the LTC3108 or LTC3109 which start at a measly 0.02V and boost it up to 3.3V <br>Or go with a LTC3105 &quot; Step-Up DC/DC Converter with Maximum Power Point Control and 250mV Start-Up&quot; which sounds nicely! <br>See http://parametric.linear.com/Energy_Harvesting for a full list
I'm Also experimenting a Joule thief circuit.. So well see how that goes.
If you want to use the classic JouleThief-Design, be sure you use a BJT (bipolar junction transistor) with a low VCE like the 2SD965, 2SD5041 or 2SC2500D.<br><br>Also be sure you check this topic here for some really good ideas and advices especially in the winding of the coils but also on &quot;inverted&quot; JouleThiefs and suggestions for Transis/FET's:<br>http://www.overunity.com/13175/25mv-joule-thief-powered-by-peltier-merely-using-our-body-heat-free-energy-247/60/<br>

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Bio: Bill Nye the Science guy is my Hero... that and Bear Grylls...would be cool if they combined to become Bear Nye the Wilderscience Guy ... More »
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