FuelCellsWorks

Seattle, Washington and Cambridge, Mass.– A project to use dirt-powered batteries to charge cell phones in Africa won a $100,000 grant from The Bill & Melinda Gates Foundation today.

Led by Aviva Presser Aiden ‘09 (Ph.D.), an affiliate of the Harvard School of Engineering and Applied Sciences (SEAS) who is now a student at Harvard Medical School, the aim is to develop a Microbial Fuel Cell-based charger that could be readily and cheaply assembled out of basic components to increase access to health care via mobile applications in the developing world. The project, hosted by the Laboratory-at-Large at Harvard, will have an initial field-test site in sub-Saharan Africa.

This grant was made under the call for Gates Grand Challenges Exploration Grant (CGE) proposals to “Create Low-Cost Cell Phone-Based Applications for Priority Global Health Conditions.”

GCE funds scientists and researchers worldwide to explore ideas that can break the mold in how to solve persistent global health and development challenges. Aiden’s project is one of over 85 Grand Challenges Explorations Round 6 grants.

Cell phones are becoming a ubiquitous and increasingly crucial part of the health care infrastructure of the developing world. The devices provide a critical gateway to health information and offer contact with physicians who cannot reach remote locations.

For instance, even in Sub-Saharan Africa, where 500 million people lack power in their homes, 22 percent of households have cell phones. Keeping the devices charged, however, can be a challenge.

“For households lacking power in Sub-Saharan Africa, recharging a cell phone battery often means a long, possibly multi-hour walk to a charging station, where recharges cost between 50 cents and a dollar,” says Aiden. “Because the per-capita income is several hundred dollars per year, this is a significant cost. Existing solutions for charging cell phones in off-grid areas are inadequate. For instance, a solar-panel based charger costs around $20, and is difficult to even bring to market because of poor access and inability to repair them if they break.”

The solution is the use of an natural abundant source of energy: microbial power. Certain naturally occurring soil microbes produce free electrons during the course of their ordinary metabolic processes. A Microbial Fuel Cell (MFC) uses a conductive surface to harvest these electrons and use them as a power source.

“We plan to develop an MFC-based cell phone charger,” says Aiden “Our goal is to make a charger would cost of order a dollar and could completely charge a phone in 24 hours. Furthermore, unlike solar panels, MFCs do not require any sophisticated materials: they can be easily assembled in only a few minutes. As cultural knowledge of MFC technology spreads, Africans will become capable of assembling their own chargers almost entirely from scratch, and at minimal cost that will be recouped with the very first recharge.”

Aiden has already demonstrated the effectiveness of the MFC-approach, building MFCs that can produce enough to power LED lights for use in homes in regions such as Tanzania and Namibia. Moreover, the MFCs were able to operate continuously in the lab for 14 months.

“With the funding from the Gates Foundation, our plan is to send two researchers to Africa for this deployment,” she says. “The researchers will spend two weeks introducing themselves and their work to the community and collecting data regarding typical phone usage behavior and recharge frequency. After this introductory period, the researchers will install the prototypes in the homes of volunteer families, showing these families about how to plug in their phones.”

Following the completion of the pilot program, Aiden hopes to follow-up with a larger-scale project, distributing chargers across broader region, thereby demonstrating the viability of this approach to charging cellular phones in developing world contexts.

“GCE winners are expanding the pipeline of ideas for serious global health and development challenges where creative thinking is most urgently needed. These grants are meant to spur on new discoveries that could ultimately save millions of lives,” said Chris Wilson, Director of Global Health Discovery at the Bill & Melinda Gates Foundation.

Hoboken, NJ–Chemical Engineering students at Stevens Institute of Technology are transforming the way that American soldiers power their battery-operated devices by making a small change: a really small change. Capitalizing on the unique properties of microscale systems, the students have invented a microreactor that converts everyday fossil fuels like propane and butane into pure hydrogen for fuel cell batteries. These batteries are not only highly efficient, but also can be replenished with hydrogen again and again for years of resilient performance in the field.

With batteries consuming a substantial amount of a soldier’s gear weight, the Army has a high interest in replacing the current paradigm of single-use batteries with a reliable, reusable power source. The Stevens-made microreactors thus have the potential to not only reduce waste from disposable batteries, but also provide American soldiers with a dependable way to recharge the batteries for the critical devices that keep them safe.

Current methods for generating fuel cell hydrogen are both sophisticated and risky, requiring high temperatures and a vacuum to produce the necessary chemical-reaction-causing plasmas. Once in a container, hydrogen is a highly volatile substance that is dangerous and expensive to transport.

The Stevens microreactor overcomes both of these barriers by using low temperatures and atmospheric pressure, and by producing hydrogen only as needed to avoid creating explosive targets in combat areas. These advanced reactors are created using cutting-edge microfabrication techniques, similar to those used to create plasma television screens, which use microscale physics to produce plasma under normal atmospheres.

The team has already had success producing hydrogen from methanol. After gasifying methanol by suspending it in hot nitrogen gas, the mixture is drawn into a 25µm channel in the microreactor. There, it reacts with plasma to cause thermal decomposition, breaking down the methanol into its elemental components. Now the team is conducting tests to see what kind of yields are realizable from various starter fuels. Eventually, soldiers will be able to convert everyday liquid fuels like propane or butane, commonly found on military bases, into high-potency juice for portable fuel cell batteries.

The team, made up of seniors Ali Acosta, Kyle Lazzaro, Randy Parrilla, and Andrew Robertson, are supporting Ph.D. candidate Peter Lindner in a research project sponsored by the U.S. Army. The project is overseen by Dr. Ronald Besser.

About the Department of Chemical Engineering and Materials Science
The mission of the Department of Chemical Engineering and Materials Science is to provide high-quality education and cutting-edge research training to students with strong disciplinary fundamentals and broad interdisciplinary and societal perspectives as adaptive experts and future leaders and innovators in their chosen profession. The programs offered by the Department produce broad-based graduates who are prepared for careers not only in traditional petrochemical, environmental, and specialty chemical industries, but also in such high technology areas as biochemical and biomedical engineering, electronic and semi-conductor processing, ceramics, plastics and high-performance materials, and electrochemical processing. Qualified undergraduates work with faculty on research projects, and many of graduates pursue advanced study in chemical engineering, bioengineering or biomedical engineering, medicine, law, and many other fields.