In response to numerous questions about what happens to the collected algae this instructable should help someone to build a microbial fuel cell (MFC) with household items and materials. As its name suggests, an MFC uses microbes to catalyze electricity-producing reactions.
This instructable is based on work done by Bruce Logan and his team at Penn State University and on the microbial fuel cells built by Abbie Groff, a student at Conestoga Valley High School in Lancaster, PA. The research she performed with her MFCs helped her win the Grand Champion Award at the 2005 Lancaster County Science Fair.
Now to be completely honest the fuel cell we will build is not "purely" an algae fuel cell, it is a microbial fuel cell that uses anaerobic bacteria to decompose organic matter, in our case dead algae.
The fuel cell will consume the algae (or other organic material) with two significant by-products, electricity (always useful) and methane gas. In a production system the methane must be captured for further use for instance as fuel for a steam powered generator which processes its exhaust plume through an algae based (or other) exhaust gas scrubber.
In this design its very cleverly captured in the sealed anode and if you come up with some clever way to do something with it, I'd be very pleased to hear it.
This instructable is based on work done by Bruce Logan and his team at Penn State University and on the microbial fuel cells built by Abbie Groff, a student at Conestoga Valley High School in Lancaster, PA. The research she performed with her MFCs helped her win the Grand Champion Award at the 2005 Lancaster County Science Fair.
Now to be completely honest the fuel cell we will build is not "purely" an algae fuel cell, it is a microbial fuel cell that uses anaerobic bacteria to decompose organic matter, in our case dead algae.
The fuel cell will consume the algae (or other organic material) with two significant by-products, electricity (always useful) and methane gas. In a production system the methane must be captured for further use for instance as fuel for a steam powered generator which processes its exhaust plume through an algae based (or other) exhaust gas scrubber.
In this design its very cleverly captured in the sealed anode and if you come up with some clever way to do something with it, I'd be very pleased to hear it.
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Signing UpStep 1: Bill of Materials
Tools:
Drill or drill press
Razor knife or scissors
Hot glue gun
Funnel - Optional for filling bottles
Soldering iron
Lead Solder
Materials and where I got them. I have no relationship with any of these stores or products. They are inexpensive and should be commonly available:
Drill or drill press
Razor knife or scissors
Hot glue gun
Funnel - Optional for filling bottles
Soldering iron
Lead Solder
Materials and where I got them. I have no relationship with any of these stores or products. They are inexpensive and should be commonly available:
- Two heavy duty plastic bottles with sealable lids. Wide mouth bottles are best choice for ease of inserting broad surface area electrodes.
- Low power aquarium air pump
- 1 x 2" PVC pipe 1-2 feet long
- 2 x 1 quart mason jars or similar
- 1 x 2" PVC Nipple or Sprinkler system riser
- 4 x PVC slip caps. You can probably get away with two, I use two for storing the salt bridge
- 2 x 1in square Silkscreen material or other nonconductive mesh
- Agar - 100g per Liter of water
- Salt - 400g per Liter of water ( 14 oz/Qt ).
- Carbon cloth or carbon paper
- Nitrogen for removing oxygen from water. This can be readily obtained from several sources locally and online.
- Welding supply places will have Nitrogen and Argon in tanks for various sizes. Around $35 for a small tank here.
- Local tire dealers. Local tire dealers often replace air in tires with nitrogen (for a fee). They will happily fill up your inner tube or inexpensive pressure tank (for a fee).
- Bacteria for a MFC can be obtained from several sources.
- Shultz Liquid Plant food
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Generally speaking this sort of design is best suited to trickle charge applications.
I m making a microbial fuel cell in which i am using a sulfides as a substrate.. and aerobic bacterial cultures. i made a two nylone made chambers with salt bridge. Now i am about to start my work and my guide told me to staderdize a fuel cell,,, so i am not getting how to standerdize a fuel cell with a use of sulfides as a subsrate. i need a help with every type of actions which carry out a good work. it will be a great help of you if you guide me as any......
http://www.instructables.com/id/Make-a-Microbial-Fuel-Cell-MFC-Part-II/
I'm a student who tried to build an mfc at home. I used waste water as the anode substance, and graphite electrodes, in both anode and cathode. But my multimeter is showing a negative voltage reading. What have I done wrong?
One quick way to degas a solution is to boil it for a few minutes. Gas solubility decreases a lot with temperature. Of course you won't be able to boil your culture, but sterilizing the media might help to keep stray yeasts out of it.
Other gases will work as well, such as helium, which is more readily available for party ballons in smaller disposable cylinders.
You can also remove the oxygen specifically by electrolyzing the solution since you have nice electrodes and a very fine salt bridge. During the electrolysis of salt water, at the cathode (-) side dissolved oxygen is reduced to hydroxide, OH-, and hydrogen gas is evolved. In the other compartment, the anode(+), oxygen gas is evolved, while acidifying the adjacent solution.
Does the algae have to have sunlight in order to do its thing?
Keep rocking this kind of cool stuff.
There is no relationship between microbial fuel cells and algae scrubbers. The output voltage from an MFC varies according to volume, microbe type and available food.
“Water desalination can be accomplished without electrical energy input or high water pressure by using a source of organic matter as the fuel to desalinate water,” reported in a recent online issue of Environmental Science and Technology. Please read more at
http://earthalternate.blogspot.com/2009/08/electricity-and-desalination-from.html
i was looking for this kind of solution for months
wow is this a miracle or what ?
Here's a link to the base article:
Direct Biological Conversion of Electrical Current into Methane by Electromethanogenesis
I would recommend the Jello based design as a test platform. It is much more adaptable and a number of configurations can be tested at once. Current can readily be applied across the electrodes or through the media depending on the experimental model.
If your goal is the production of methane I would suggest that you will get better results with an algae farm. There are numerous tank designs that will scale up extremely well. The energy input cost, even with pumps, is lower. The Chinese have reported ( in peer reviewed journals, see the Journal of Power Sources ) that get 1L of methane for each liter of algae sludge mixed with approximately 50% paper pulp.
The sludge and pulp is placed into an anaerobic digester and the methane captured. The exhausted sludge is dried and used as a high grade fertilizer.
All of these technologies are low-tech and within the grasp of virtually anyone.
Without it the agar (or other salt bridge media) will break down and collapse quite rapidly (eventually it will completely degrade in any event). A mechanical support ( such as silkscreen material ) can delay that.
I'm not sure where exactly to go to get access to it. Also, should the agar be touching this material when its actually placed over the pipe?
Sorry for taking your time.
I would place it over the end when I poured in the gelatin/electrolyte mixture, This will bind the agar and the mesh together.
Also consider possibly cutting out a circle or two that will fit in the pipe and can be manipulated down onto the interior surface.
You might try one or two without worrying about the mesh just to work out the rest of the process details and get an idea of expected voltages over, say, a week or two.
http://groups.google.com/group/DIYbio-SF/browse_thread/thread/f2178d7f12c053a7
For the amount of text I'd expect pictures of this being made, can you get some?
L