Slashdot Mirror
Another Step Forward In Small Scale Electrical Generators
NicknamesAreStupid writes "Product Design & Development reports another breakthrough in small scale solid oxide fuel cells. This methane-fueled cell achieves about 50% efficiency at around 2kW, enough to power an average home. It does so by efficiently recycling its heat to perpetuate the process. Of course, this is not practical for most homes, which only have natural gas that contains nearly one fifth impurities. However, that could change if gas suppliers refined their product."
Could it be used on board an electric vehicle to provide power in lieu of a battery?
No. Even though solid oxide fuel cells work and are commercially available (in larger sizes), they have problems for automobile applications - to run efficiently, they operate close to 1000 degrees C, and they don't like being bounced around. Dealing with that kind of temperature in a car is a problem.
For mobile applications, PEM fuel cells are far more likely to be practical.
A classic problem with fuel cells is extreme intolerance to contaminants. Even trace amounts of contaminants tend to damage fuel cells. Hydrogen fuel cells need cleaner hydrogen than is normally available commercially. Research continues on making fuel cells more tolerant of contaminants, but it's hard. Fuel cells are surface chemistry systems. 40 years of research hasn't solved this problem.
Reverse osmosis water purification systems once had the same problem. Today they routinely take in raw seawater and pump out clear water. They just need a backflush cycle once in a while to flush the crud off the membranes. Fuel cells aren't there yet.