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(the following is a guest post from Abdul-Majeed Azad, associate professor, chemical engineering, University of Toledo)

As we know, the ultimate chemical fate of the conventional fossil fuel combustion is always CO₂ and H₂O, two well-known greenhouse gases responsible for contributing considerably to the global warming. In 2007 the global level of CO₂ was 30 billion metric ton and is projected to be 43 billion metric ton by 2030. The United States contributes the largest amount - 22.2% - of global CO₂ emissions.

What if we could convert CO₂ into carbon monoxide (CO), water into H₂ and a mixture of CO₂+H₂O (the ultimate product of complete combustion of hydrocarbon-based fossil fuels, including biofuels) into syngas (CO+H₂), respectively? Syngas is a valuable precursor for the well-known Fischer-Tropsch process perfected by Germans during WW II to make synthetic fuels since Germany had coal but no oil reserves. All these streams (CO, H₂ and CO+H₂) are also ideal fuels for solid oxide fuel cells. Hence, essentially the waste products of combustion could become a fuel source and can be recycled. Alternatively, if desired, CO could be converted into H₂ via catalytic water-gas-shift reaction that then could become feed for proton exchange membrane fuel cells.

We have developed an inexpensive heterogeneous ceramic catalyst that we experimentally found capable of converting CO₂ and H₂O into CO and H₂, respectively, on a 1:1 molar basis, under mild temperature and atmospheric pressure. These streams when fed into an intermediate temperature SOFC at 650°C create an open circuit voltage, quite comparable to that of the same SOFC run with pure H₂.

The technology is also of relevance to NASA’s in-situ resource utilization program for MARS exploration since Martian atmosphere is ~ 96% CO₂. NASA might be interested in looking at our technology for creating CO from Martian CO₂ and, use it either as such or after water-gas-shift reaction to generate hydrogen as fuel for a SOFC stack. In the Martian context, to make the process truly self-sustained one could use solar concentrators to generate enough heat to raise the temperature to cause the desired conversion (CO₂ to CO to H₂). Thus, the fuel can be generated (and used) during daytime and stored and utilized to run fuel cells in the night hours.

It is predicted that global clean energy markets are going to quadruple in the next decade from $55.4 billion in revenue in 2006 to more than $226.5 billion by 2016. The approximate market size of this greenhouse gas mitigation is over $1 billion. The technology and the product are potentially of interest to energy producers and suppliers, utility chains, SOFC manufacturers and users, organic synthesis companies and Mars human exploration missions. The United States Department of Defense uses logistic fuels for its operations and could employ the greenhouse gas-fueled SOFC technology for many military field operations, including mobile forward base units, auxiliary field hospitals, field command posts, operational forays, and unmanned aerial vehicles. NASA is also currently looking at non-petroleum-based jet fuels in the pursuit of alternative fuels that can power commercial jets and address rising oil costs. A greenhouse gas-derived F-T fuel could respond to that quest.

Testing took place at the Southwest Research Institute, an independent R&D facility in San Antonio, Texas. Here, paired with a lithium battery, AMI’s SOFC system gave life to a Packbot, proving that, “Lightweight, convenient and powered by globally-available propane, Adaptive Materials’ fuel cells improve the overall functionality and duration of a robot in mission-critical settings,” reports AMI’s chief business officer Michelle Crumm. Although the army currently utilizes unmanned automated systems to disarm explosive devices, Crumm explains that many more military uses for the robots could be found, if their operational time could be extended.  She says long-running robots could even be helpful in nonmilitary situations, such as searching potentially harmful debris for survivors in the aftermath of a disaster. Crumm says AMI’s goal is to develop a SOFC that can power a small ground robot for 12 hours or more. She disses competitive fuel-cell systems based on hydrogen or methanol, saying that AMI’s propane-based system offers greater potential for commercialization because propane is readily available around the world.

The DuPont/Smart Fuel Cell Team came out the million-dollar winner Oct. 8 in the Department of Defense’s Wearable Power Prize competition. DuPont is based in Delaware and SFC is headquartered in Brunnthal, Germany. DuPont has a minority stake in SFC and the group’s methanol-powered pack actually began to be deployed among combatants this summer:

“Our fuel cell technology represents a major breakthrough in portability that will benefit soldiers through significant weight reduction, while providing a prolonged source of power,” said Cynthia Green, VP and general manager of DuPont Fluoroproducts.

The contest was launched in the summer of 2007, initiated by the DOD’s Research and Engineering Directorate to fuel innovation and competition to develop a long-life, light-weight power pack for soldiers. Initially, 169 groups submitted entries. The group was narrowed to six finalists that were put to another round of testing Oct. 4 at the Marine Corps’ Air Ground Combat Center at Twentynine Palms, Calif. The minimum requirement was that the power packs had to be able to produced 20 watts average power for 96 hours and weigh less than 4 kilograms. According to the DOD news release, the winner’s power pack operated longer than the minimum, but offered no specifics:

DuPont/SFC won the competition by building the lightest wearable system that provided an average of 20 watts of power for more than 96 hours and weighed less than 4,000 grams, or 8.8 pounds.

Adaptive Materials of Ann Arbor, Mich., won  $500,000 for second place for their propane fueled solid oxide fuel cell. Jenny 600S of Middleburg, Va., won the $250,000 third place prize. DOD seems happy with the results of the competition:

“The winners, and really all the teams that competed, have moved wearable power technology forward,” said William Rees Jr., the deputy under secretary for defense laboratories and basic sciences. “But the real winners from this competition are our ground warfighters, as these systems show great promise to reduce the weight of batteries they have to carry while performing their critical missions.” Rees, who sponsored the DOD Wearable Power Prize, also hopes this competition will inspire scientists and engineers. “The rules we developed for this DOD competition attracted small businesses, individual inventors, and large companies alike,” said Rees. “Our nation has tremendous capacity for innovation, so we hope that this and future competitions also motivates the scientific community to continue important advancements in technology.” . . . “The M-25 has the capability to revolutionize wearable portable power sources in the field by extending soldier-mission times to 72 hours and beyond,” said Col. Richard Hansen, project manager of the Soldier Warrior program of the U.S. Army.