Make a Microbial Fuel Cell (MFC) - Part 1

Step 9 Operating your MFC

Now if you attach an external circuit through a resistor you should begin getting voltage out of your MFC. The voltage will increase the bacterial population grows and then begin to decrease.

If you don't get voltage there could be any number of good reasons, including the culture. Try again, make sure you get a good seal on the anode.

Electrode construction and connectivity is also important.

For more information and design alternative on Microbial fuel cells I recommend

Dr. Bruce Logan's excellent work

Abigail Groff's outstanding page on her award winning project. Without her work this instructable would not be done.

And don't forget the folks at MicrobialFuelCell.org

I hope you enjoyed this instructable, I will be updating and revising as time goes on.

Comments

[TsarTony]

It seems to me that a resistor is necessary to a fuel cell's operation. What resistance, in this manner, should be applied?

[egbertfitzwilly]

As you probably know resistance is a function of load. This design, as with many others, are designed for scientific purposes ( such as science fair projects ). Due to natural variation in resistor manufacturing ( normally +- 10% ) the only scientifically reproduceable voltage is the open circuit voltage. Obviously once a load is applied current and voltage vary.

Generally speaking this sort of design is best suited to trickle charge applications.