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Microbial Fuel Cell Project
Moderators: AmyCowen, kgudger, bfinio, MadelineB, Moderators
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jaredcooperscience
- Posts: 1
- Joined: Tue Jan 06, 2015 5:35 am
- Occupation: Student
- Project Question: Microbial fuel cell
- Project Due Date: 1/20/15
- Project Status: I am conducting my experiment
Microbial Fuel Cell Project
Hello my name is Jared. I built the Microbial Fuel Cell and got everything set up. I have the electrodes with copper wire and a conductive epoxy connecting them to the carbon cloth. I obtained the benthic mud from a lower stream and also have the stream water which I made into the salt solution in the cathode. I have a 220 ohm resistors connected by alligator clips to the electrodes. I have measured the voltage with my multimeter and I am using the 200 m setting. The voltage is around 1-5 volts for each cell and I was wondering if this is normal or if it should be higher? I read on science buddies that I should try adding salt to the anode with the mud to increase the voltage, but I am unsure of how much to add or if I should do this. My next step is to add my substrates (mushroom compost, manure compost, or coffee grounds) but I am unsure of when to add them because I don't know if the voltage is normal now or not. Thank you for your time.
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SciB
- Expert
- Posts: 2071
- Joined: Fri Feb 01, 2013 7:00 am
- Occupation: Retired molecular biologist, university researcher and teacher
- Project Question: I wish to join Scibuddies to be able to help students achieve the best science project possible and to understand the science behind it.
- Project Due Date: n/a
- Project Status: Not applicable
Re: Microbial Fuel Cell Project
Hi Jared,
Sounds like an interesting project. So, is your hypothesis that feeding soil bacteria with compost will make them produce more electric power? Do let us know what you find out.
How long has the MFC been operating? I think the 200m setting refers to a range of 0 to 200 mV, so your readings of 1 – 5 are not volts but millivolts. For a 220 ohm resistor, this voltage is pretty good. Did you calculate the power? Did you measure the mV across some resistors with higher ohms? They should read a higher mV and higher power.
If you are planning to test the effects of adding your substrates on the power output of the MFC, I would not add salt to the mud. Be careful when you mix in the substrates, if that is what you plan to do, because if you disturb the mud next to the anode it can reduce the bacterial activity, at least temporarily.
Temperature is important for good MFC operation. The cell works best in the 30-40C range (http://www.ncbi.nlm.nih.gov/pubmed/22097080) so if it is in a cold room you might want to move it somewhere warmer.
Remember, it takes a day or sometimes longer for the MFC to restabilize after you make a change to the mud, so be sure to continue taking readings until they stop changing.
Good luck!
Sybee
Sounds like an interesting project. So, is your hypothesis that feeding soil bacteria with compost will make them produce more electric power? Do let us know what you find out.
How long has the MFC been operating? I think the 200m setting refers to a range of 0 to 200 mV, so your readings of 1 – 5 are not volts but millivolts. For a 220 ohm resistor, this voltage is pretty good. Did you calculate the power? Did you measure the mV across some resistors with higher ohms? They should read a higher mV and higher power.
If you are planning to test the effects of adding your substrates on the power output of the MFC, I would not add salt to the mud. Be careful when you mix in the substrates, if that is what you plan to do, because if you disturb the mud next to the anode it can reduce the bacterial activity, at least temporarily.
Temperature is important for good MFC operation. The cell works best in the 30-40C range (http://www.ncbi.nlm.nih.gov/pubmed/22097080) so if it is in a cold room you might want to move it somewhere warmer.
Remember, it takes a day or sometimes longer for the MFC to restabilize after you make a change to the mud, so be sure to continue taking readings until they stop changing.
Good luck!
Sybee