Capturing power at higher voltages from arrays of microbial fuel cells without voltage reversal

Handle URI:
http://hdl.handle.net/10754/597724
Title:
Capturing power at higher voltages from arrays of microbial fuel cells without voltage reversal
Authors:
Kim, Younggy; Hatzell, Marta C.; Hutchinson, Adam J.; Logan, Bruce E.
Abstract:
Voltages produced by microbial fuel cells (MFCs) cannot be sustainably increased by linking them in series due to voltage reversal, which substantially reduces stack voltages. It was shown here that MFC voltages can be increased with continuous power production using an electronic circuit containing two sets of multiple capacitors that were alternately charged and discharged (every one second). Capacitors were charged in parallel by the MFCs, but linked in series while discharging to the circuit load (resistor). The parallel charging of the capacitors avoided voltage reversal, while discharging the capacitors in series produced up to 2.5 V with four capacitors. There were negligible energy losses in the circuit compared to 20-40% losses typically obtained with MFCs using DC-DC converters to increase voltage. Coulombic efficiencies were 67% when power was generated via four capacitors, compared to only 38% when individual MFCs were operated with a fixed resistance of 250 Ω. The maximum power produced using the capacitors was not adversely affected by variable performance of the MFCs, showing that power generation can be maintained even if individual MFCs perform differently. Longer capacitor charging and discharging cycles of up to 4 min maintained the average power but increased peak power by up to 2.6 times. These results show that capacitors can be used to easily obtain higher voltages from MFCs, allowing for more useful capture of energy from arrays of MFCs. © 2011 The Royal Society of Chemistry.
Citation:
Kim Y, Hatzell MC, Hutchinson AJ, Logan BE (2011) Capturing power at higher voltages from arrays of microbial fuel cells without voltage reversal. Energy Environ Sci 4: 4662. Available: http://dx.doi.org/10.1039/c1ee02451e.
Publisher:
Royal Society of Chemistry (RSC)
Journal:
Energy & Environmental Science
KAUST Grant Number:
KUS-I1-003-13
Issue Date:
2011
DOI:
10.1039/c1ee02451e
Type:
Article
ISSN:
1754-5692; 1754-5706
Sponsors:
This research was supported by funding through the King Abdullah University of Science and Technology (KAUST) (Award KUS-I1-003-13).
Appears in Collections:
Publications Acknowledging KAUST Support

Full metadata record

DC FieldValue Language
dc.contributor.authorKim, Younggyen
dc.contributor.authorHatzell, Marta C.en
dc.contributor.authorHutchinson, Adam J.en
dc.contributor.authorLogan, Bruce E.en
dc.date.accessioned2016-02-25T12:55:34Zen
dc.date.available2016-02-25T12:55:34Zen
dc.date.issued2011en
dc.identifier.citationKim Y, Hatzell MC, Hutchinson AJ, Logan BE (2011) Capturing power at higher voltages from arrays of microbial fuel cells without voltage reversal. Energy Environ Sci 4: 4662. Available: http://dx.doi.org/10.1039/c1ee02451e.en
dc.identifier.issn1754-5692en
dc.identifier.issn1754-5706en
dc.identifier.doi10.1039/c1ee02451een
dc.identifier.urihttp://hdl.handle.net/10754/597724en
dc.description.abstractVoltages produced by microbial fuel cells (MFCs) cannot be sustainably increased by linking them in series due to voltage reversal, which substantially reduces stack voltages. It was shown here that MFC voltages can be increased with continuous power production using an electronic circuit containing two sets of multiple capacitors that were alternately charged and discharged (every one second). Capacitors were charged in parallel by the MFCs, but linked in series while discharging to the circuit load (resistor). The parallel charging of the capacitors avoided voltage reversal, while discharging the capacitors in series produced up to 2.5 V with four capacitors. There were negligible energy losses in the circuit compared to 20-40% losses typically obtained with MFCs using DC-DC converters to increase voltage. Coulombic efficiencies were 67% when power was generated via four capacitors, compared to only 38% when individual MFCs were operated with a fixed resistance of 250 Ω. The maximum power produced using the capacitors was not adversely affected by variable performance of the MFCs, showing that power generation can be maintained even if individual MFCs perform differently. Longer capacitor charging and discharging cycles of up to 4 min maintained the average power but increased peak power by up to 2.6 times. These results show that capacitors can be used to easily obtain higher voltages from MFCs, allowing for more useful capture of energy from arrays of MFCs. © 2011 The Royal Society of Chemistry.en
dc.description.sponsorshipThis research was supported by funding through the King Abdullah University of Science and Technology (KAUST) (Award KUS-I1-003-13).en
dc.publisherRoyal Society of Chemistry (RSC)en
dc.titleCapturing power at higher voltages from arrays of microbial fuel cells without voltage reversalen
dc.typeArticleen
dc.identifier.journalEnergy & Environmental Scienceen
dc.contributor.institutionPennsylvania State University, State College, United Statesen
kaust.grant.numberKUS-I1-003-13en
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