Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:


Cheaper wastewater-fueled device produces more electricity


Penn State environmental engineers have removed and replaced one of the most expensive parts of their prototype microbial fuel cell and the device now costs two-thirds less and produces nearly six times more electricity from domestic wastewater.

Earlier this year, the Penn State team was the first to develop a microbial fuel cell (MFC) that can generate electricity while simultaneously cleaning domestic wastewater skimmed from the settling pond of a sewage treatment plant. Now, they’ve shown that by modifying their original MFC to make it cheaper, they can also boost electricity production from about 26 milliwatts per square meter to about 146 milliwatts per square meter.

Dr. Bruce Logan, the Kappe professor of environmental engineering, directs the project. He says, "The new design has moved the technology closer to our goal of 1000 milliwatts per square meter."

He notes that they have hooked up an MFC built on the Penn State design principles to run a three-milliWatt fan. (See video at Calculations show that a typical wastewater treatment plant that had a Penn State MFC in place could power the fan with just 5.5 oz of wastewater or a reactor smaller than a teacup.

The advance is described in a paper, Electricity Generation Using an Air-Cathode Single Chamber Microbial Fuel Cell in the Presence and Absence of a Proton Exchange Membrane, released online and scheduled for a future issue of Environmental Science and Technology. The authors are Dr. Hong Liu, postdoctoral researcher in environmental engineering, and Logan.

The Penn State team modified their original fuel cell by removing the polymeric proton exchange membrane (PEM) that previously was bonded to the cathode and substituting carbon paper for the electrodes.

Microbial fuel cells produce current through the action of bacteria that can pass electrons to an anode, the negative electrode of a fuel cell. The electrons flow from the anode through a wire to a cathode, the positive electrode of a fuel cell, where they combine with hydrogen ions (protons) and oxygen to form water.

The naturally-occurring bacteria in wastewater drive power production via a reaction that allows them to transport electrons from their cell surface to the anode. In addition, a reaction (oxidation) that occurs in the interior of the bacterial cell lowers the biochemical oxygen demand, cleaning the water.

The new prototype consists of carbon paper placed on opposite ends of a plastic tube about an inch and a half long and a little over an inch in diameter. Carbon paper on one end is the anode and carbon paper, which also contains a small amount of platinum, forms the cathode on the other end. Platinum wire completes the circuit. The carbon paper allows oxygen in air to directly react at the cathode. So, there is no need to bubble air into the water at the cathode as is required in a typical two chamber MFC.

Logan notes, "By eliminating the PEM, which was one of the most expensive components, we bring the cost down significantly. Substituting carbon paper for graphite rods further reduces the cost. I’m optimistic that MFCs may be able to help reduce the $25 billion annual cost of wastewater treatment in the U.S. and provide access to sanitation technologies to countries throughout the world."

The project was supported by a grant from the National Science Foundation and Penn State’s Huck Institute of Life Sciences.

Barbara Hale | EurekAlert!
Further information:

All articles from Power and Electrical Engineering >>>

The most recent press releases about innovation >>>

Die letzten 5 Focus-News des innovations-reports im Überblick:

Im Focus: Locomotion control with photopigments

Researchers from Göttingen University discover additional function of opsins

Animal photoreceptors capture light with photopigments. Researchers from the University of Göttingen have now discovered that these photopigments fulfill an...

Im Focus: Surveying the Arctic: Tracking down carbon particles

Researchers embark on aerial campaign over Northeast Greenland

On 15 March, the AWI research aeroplane Polar 5 will depart for Greenland. Concentrating on the furthest northeast region of the island, an international team...

Im Focus: Unique Insights into the Antarctic Ice Shelf System

Data collected on ocean-ice interactions in the little-researched regions of the far south

The world’s second-largest ice shelf was the destination for a Polarstern expedition that ended in Punta Arenas, Chile on 14th March 2018. Oceanographers from...

Im Focus: ILA 2018: Laser alternative to hexavalent chromium coating

At the 2018 ILA Berlin Air Show from April 25–29, the Fraunhofer Institute for Laser Technology ILT is showcasing extreme high-speed Laser Material Deposition (EHLA): A video documents how for metal components that are highly loaded, EHLA has already proved itself as an alternative to hard chrome plating, which is now allowed only under special conditions.

When the EU restricted the use of hexavalent chromium compounds to special applications requiring authorization, the move prompted a rethink in the surface...

Im Focus: Radar for navigation support from autonomous flying drones

At the ILA Berlin, hall 4, booth 202, Fraunhofer FHR will present two radar sensors for navigation support of drones. The sensors are valuable components in the implementation of autonomous flying drones: they function as obstacle detectors to prevent collisions. Radar sensors also operate reliably in restricted visibility, e.g. in foggy or dusty conditions. Due to their ability to measure distances with high precision, the radar sensors can also be used as altimeters when other sources of information such as barometers or GPS are not available or cannot operate optimally.

Drones play an increasingly important role in the area of logistics and services. Well-known logistic companies place great hope in these compact, aerial...

All Focus news of the innovation-report >>>



Industry & Economy
Event News

Ultrafast Wireless and Chip Design at the DATE Conference in Dresden

16.03.2018 | Event News

International Tinnitus Conference of the Tinnitus Research Initiative in Regensburg

13.03.2018 | Event News

International Virtual Reality Conference “IEEE VR 2018” comes to Reutlingen, Germany

08.03.2018 | Event News

Latest News

Wandering greenhouse gas

16.03.2018 | Earth Sciences

'Frequency combs' ID chemicals within the mid-infrared spectral region

16.03.2018 | Physics and Astronomy

Biologists unravel another mystery of what makes DNA go 'loopy'

16.03.2018 | Life Sciences

Science & Research
Overview of more VideoLinks >>>