Chapter 19, Problem 84IAE

Interpretation Introduction

Interpretation:

Whether the efficiency value of fuel cells should have a value greater than one should be explained.

Concept introduction:

In fuel cell, chemical energy of fuels is directly converted into electricity. The major process in a fuel cell is oxidation of fuel.

The theoretical maximum energy available as electric energy in any electrochemical cell is equal to ${\Delta }_r{G}^0$ for the reaction. The maximum energyrelease when a fuel is burned is ${\Delta }_r{H}^0$. One of the measures used to evaluate afuel cell is the efficiency value.

Efficiency value = $\frac{{\Delta }_r{G}^0}{{\Delta }_r{H}^0}$