The SOFC electrolyte is a ceramic membrane, often yttrium stabilized zirconia (YSZ). The electrodes are porous, conducting metal-ceramics. The transfer ion is O2-. To get the ion conductivity necessary, the SOFC system operates at high temperatures, usually 1000C. There are some new methods being developed to reduce that to 500C to 800C. Because of the high temperature operation, a catalyst is not needed at the electrode-electrolyte interface. Back to Third Orbit Home Page Drawing of the basic PEM fuel cell operation Drawing showing how a stack of PEM cells work Figure showing configuration options for fuel cell utility systems Figure showing source, process, storage and load options for remote renewable utility systems Remote renewable hydrogen village using a fuel cell Comparison of civilization's development in food and energy