WARNING: Most of the time I write my articles aimed at topics and ideas that are directed for a homeowner, business owner, or property manager. The articles discuss some easily applicable, or at least palatable topic that may be useful or helpful for an energy plan within the near future. This is not one of those articles…
Today’s topic is Microbial Fuel Cells.
What the what?
Yes you read correctly, microbial fuel cells (MFC). MFCs are systems designed to take a living organism and generate an electrical current from its natural metabolism. For those of you around my age, you may be thinking of the scene from the Matrix. That’s exactly the idea.
However, instead of using human, scientists are trying to design useful microbial fuel cells that run off of bacteria processes. And, to make the matter even more appealing, many scientists are looking to use bacteria (or algae) that run off of wastewater or other trash in order to generate the electricity from, what otherwise, would be discarded.
But how would such a system work?
Well, I could do some hand waving and just say that the bacteria, when it is ‘digesting’ its food create a chemical that establishes an energy gradient. This gradient is then channeled into a current, and voila, you have electricity. However, let’s get into a bit more detail.
So, imagine we have a container and on the left is a liquid substrate rich with bacteria and on the right is an oxygen rich solution. Connecting these two halves are an electrical wire, with an anode in the bacteria side and a cathode in the oxygen side.
Now, imagine that the bacteria has to undergo anaerobic respiration in order to process its food source. This anaerobic condition is simulated by depriving the bacteria side of the MFC from oxygen. In order to finish the metabolic cycle, the bacteria must transfer an electron from the Anode. This, coupled with the voltage difference between the canoed and the cathode, causes electricity to be generated within the MFC.
Now, let’s be realistic for one moment, MFCs are far from ideal systems at the time being. In fact, one might even say that the current state of MFC implementation is infantile. The MFC systems running are poorly regulated (from an electronical perspective) and to make matters worse are still struggling to find a viable species off which to run.
These are by no means insurmountable issues, however. A similar thing could have been said for the state of bioremediation within pollution zone not too long ago. However, from a combination of active research and incentive (driven by super fund money), bioremediation has drastically improved from an efficacy perspective.
In the case of MFCs, it is really a market changer. Of course MFCs are not adequate at this time to cope with all of the energy needs that a developed nation requires. Just from an energy balance standpoint, there is not enough material for us to power the grid we do with MFCs. With that said, MFCs do provide a glimpse into a system that could be more energy efficient.
For instance, our wastewater treatment facilities at present use A LOT of energy to just pump the water and treat it. This energy could, in theory, be self-powered by the tactical implementation of MFCs within the wastewater treatment process. Much of the nutrients necessary for bacteria to thrive could come from the wastewater plants. Similar approaches could be done at landfills and compost sites.
Not to mention, the process of MFCs does not lend itself to methane generation and the potential methane escape that convention landfill WTE methods rely upon.
To read more about MFCs check out the following links:
http://www.engr.psu.edu/ce/enve/logan/bioenergy/research_mfc.htm
http://www.h2journal.com/displaynews.php?NewsID=735
And as usual, for all your energy thoughts and news check out www.energygridiq.com today!
No comments:
Post a Comment