Editor's Note: A team of Rensselaer Polytechnic Institute students are traveling up New York's Hudson River this week on the New Clermont, a 6.7-meter boat outfitted with a pair of 2.2-kilowatt hydrogen fuel cells to power the boat's motor. Their journey began September 21 from Manhattan's Pier 84 and will cover 240 kilometers (at a projected speed of 8 kilometers per hour). After making several stops along the way, the crew expects to arrive back at Rensselaer Polytech's campus in Troy, N.Y., on September 25. This is the third of Scientific American.com's blogs chronicling this expedition, called the New Clermont Project.
The New Clermont Project crew is learning valuable lessons about what it will take to make hydrogen power not only possible but practical as well. After losing both hydrogen fuel-cell-powered boat motors Tuesday, the New Clermont spent Wednesday docked in Beacon, N.Y., while the Rensselaer students figured out what went wrong.
"Our Plug Power GenDrive fuel cell units work wonderfully in the context of the materials handling environment, to power the forklifts for which they were designed," William Gathright, a doctoral student in Rensselaer's Materials Science and Engineering Department and the project's leader, blogged Wednesday. "The trolling motors we are using are flawless in the typical application attached to marine batteries. But combine the fuel cell units and the motors with some improbably long cables and the Law of Unintended Consequences takes effect."
The analysis: One of the diodes or MOSFETs (metal–oxide–semiconductor field-effect transistor) within the motor controller was damaged. A MOSFET is used to amplify or switch electronic signals.
"Our workaround was ruthless but effective," Gathright blogged. "We bypassed the motor controller entirely cutting the 'brains' (controller) out of the system leaving only the 'legs' (the motor itself)." This means that as the New Clermont continues its voyage today, the crew will have to manually regulate the speed of the motors.
Reflecting on Wednesday's troubleshooting session, Gathright noted that the technology available to create hydrogen-powered vehicles and vessels exists. "It is the endless permutations, the heretofore unimagined combinations of these technologies that can introduce quirks," he added.
Images courtesy of Rensselaer Polytechnic Institute