Analysis

Estimate the range of current and voltage for which the fuel cell is a viable energy source.

Use the measured fuel consumption at each cell condition you selected and use this to obtain a pragmatic efficiency for the production of electricity:

Efficiency = h = (what you get) / (what you pay for)

Compare this efficiency with the thermodynamic estimate for the ideal cell.

How does the Fuel Cell efficiency compare to the efficiency of an ideal Carnot engine using hydrogen as the fuel, air as the oxidizer, and access to an infinite reservoir at
20 C? The adiabatic flame temperature of a stoichiometric hydrogen-air flame is 2400 K.