Smoltek Hydrogen and Heraeus Precious Metals are preparing a 3,000 hour durability test of a porous transport electrode designed to operate with less than 0.1 mg of iridium per square centimeter. The test, scheduled to begin in autumn, will examine the long term stability of Smoltek’s nanostructured iridium catalyst layer under operating conditions. Smoltek Hydrogen is developing a porous transport electrode in which the iridium catalyst is structured at the nanoscale. The planned 3,000 hour campaign is therefore more consequential than a demonstration of low iridium loading alone. Consequently, an ultra low iridium electrode would need to demonstrate competitive performance across the entire operating envelope rather than only under controlled laboratory conditions.