Fuel Cell Sizing - UAlberta-EcoCar/wiki GitHub Wiki
Based on section 10.1.9 of Santin. Et Al (Pac Car Book) "a FCS is most efficient, not at full power, but at about 1/3 power (section 10.1.8)" This has been our rule of thumb for sizing a fuel cell. A more detailed analysis must be also conducted to ensure the Fuel Cell will supply sufficient voltage to the motors at it's operating point. See motor sizing calculations section for more info on this.
As also indicated in Santin Et. Al, while the Fuel cell is oversized, the other components of the fuel cell system should be appropriately sized for the loads expected.