WARF: P09073US
Light-Powered Microbial Fuel Cell Offering Clean, Renewable Hydrogen-Based Alternative Energy Source

INVENTORS

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Daniel Noguera, Timothy Donohue, Marc Anderson, Katherine McMahon, M. Isabel Tejedor-Anderson, Yun Cho, Rodolfo Perez

One of the greatest challenges of our time is the need for new, renewable sources of energy to offset modern society’s dependence on fossil fuels.  One clean technology of interest is a hydrogen-based fuel cell.

A hydrogen fuel cell is comprised of an electrolyte sandwiched between two electrodes.  Oxygen passes over one electrode and hydrogen over the other, generating electricity, water and heat. In microbial fuel cells (MFC), bacteria convert an organic substrate, such as sugar or waste water, into carbon dioxide, protons and electrons, which then may be used to generate hydrogen for powering the fuel cell.

UW-Madison researchers previously developed an MFC that exploits the photosynthesis process to provide a renewable energy source.  The fuel cell is comprised of a single light-admitting reaction chamber made of a translucent material, such as glass or plastic.  Within the chamber is a cathode, an anode, a growth medium and a culture of photoheterotrophic bacteria, such as Rhodobacter sphaeroides strain 2.4.1.  When the bacteria are exposed to light, they generate hydrogen from the organic growth medium.  The hydrogen produced at the anode then reacts with oxygen on the cathode to produce electrical energy, with water as the only byproduct. UW-Madison researchers now have developed an alternative surface for their MFC that is both transparent and catalytic.  Specifically, they have improved the MFC by producing transparent anodes consisting of a glass substrate, a conductive layer made of indium tin oxide (ITO) and layers of a porous catalytic coating with titanium dioxide (TiO₂) and platinum.  These anodes can catalyze the oxidation of dissolved H₂ in abiotic and biological systems.

• Many economic incentives exist for developing and commercializing hydrogen-based energy, including hydrogen production. 
• The overall United States hydrogen market was estimated at $798.1 million in 2005 and is expected to rise to $1.605 billion in 2010.
• Since more than 99 percent of hydrogen is produced from fossil fuels, the current market for biomass-, solar- or nuclear-produced hydrogen is less than $1 million but expected to grow with the decreasing reliance on fossil fuels.

• Powering automobiles, power grids, laptops and other applications in the transportation, energy and electronics industries
• Treating organic waste
• Direct hydrogen production for use in hydrogen fuel cells

• Provides a highly renewable organic fuel source that is carbon neutral
• Converts chemical energy stored in organic materials into electrical energy
• Increases efficiency of microbial fuel cells
• Provides solar alternative to fossil fuels
• Generates hydrogen more efficiently than electricity
• Poses no known threat from pollution or greenhouse gas
• Photosynthetic microbes are well adapted to capture solar energy.
• May use organic sediment, waste water or agricultural waste as growth medium
• Photosynthetic organism may include Rhodospirillaceae, Acetobacteraceae, Bradyrhizobiaceae, Hyphomicrobiaceae, Rhodobiaceae, Rhodobacteraceae, Rhodocyclaceae  or Comamonadaceae
• All reactions take place in a single chamber, which may be one of various shapes.
• Anode surface is both transparent and catalytic.
• Anode may be heated to modulate abrasion resistance.
• Photosynthetic organism may be manipulated to produce more hydrogen.

For current licensing status, please contact our team at licensing@warf.org or phone 608.262.4924. (Clicking this link will open a contact form in a popup window. If you have problems viewing the form, try disabling your popup blocker software.)