Next Generation Electric Power; Hydrogen Fuel Cells
Posted on October 21, 2009 by aaronredbaron
While the topic of today’s article may well be out of reach for the average hobbyist for many years, the potential is exhilarating! Recent advancements in Lithium battery technology have opened up possibilities for electric flight. No longer are electric models limited by heavy batteries which could not deliver adequate power. Today’s Lithium batteries have the ability to provide remarkable power with minimal weight, but endurance is still limited. While the demand for long flight times isn’t as critical in the hobby, it plays a major role in the function of UAVs. While a battery powered electric model can be deliver exceptional performance, its flight time is usually limited to 5-20 minutes, depending on power demands. Hydrogen fuel cells have been around for longer than most of the battery technology we rely on, but it has only been recently that fuel cell development has taken huge leaps.
A hydrogen fuel cell is a device which uses Hydrogen and Oxygen to produce electricity, with pure water vapor and heat being the by-products. Only recently have systems been developed which take advantage of the best attributes of both in one power package. These next generation power system uses Lithium batteries to provide the immediate (burst) current needed for short periods, while a fuel cell provides the longevity and keeps the lithium batteries charged when power demands are lower. In a UAV, for example, the Lithium battery would provide the necessary power to accelerate the model for the take-off and climb phases of the flight, and the fuel cell would provide the low levels of power over long periods of time for the cruise phase of the flight. Two fuel cell manufacturers are now flying unmanned aircraft with these types of systems and achieving astounding flight times. Energyor Technologies Inc of Montreal, Canada is achieving up to 10 hours of flight time with a 10 kg aircraft. Horizon Fuel Cell Technologies, based out of Singapore, powers a 9 kg UAV delivering 9 hours of endurance, which has already been licensed for flights in Isreal and is graded as a “mature” system. Horizon Fuel Cell Technologies even has an RC car available for purchase which runs on one of these Hydrogen fuel cell systems.
While it might not be practical to use fuel cells in our model aircraft due to cost limitations, its possible all kinds of future technologies could hinge on the further development of these types of systems. While we as hobbyists may not get to use these hybrid power systems in our own models, its thrilling to be watch this technology mature. These same types of hybrid systems which have allowed for such a huge increase in the endurance capabilities of UAV’s may someday provide power for human transportation.
