How to use the fuel cell thermodynamic efficiency calculator
Find the maximum efficiency of a fuel cell from the Gibbs energy and enthalpy of its reaction. Enter enthalpy of reaction, gibbs free energy of reaction in the fields above; the maximum thermodynamic efficiency, heat not convertible to work are computed instantly and plotted on the chart so you can see how the answer changes.
Common searches this calculator answers include “fuel cell efficiency”, “hydrogen fuel cell maximum efficiency”, “ΔG over ΔH”, “calculate fuel cell thermodynamic efficiency”, “find maximum thermodynamic efficiency”.
Formula
Variables
- dH — Enthalpy of reaction (kJ/mol)
- dG — Gibbs free energy of reaction (kJ/mol)
Worked example
With enthalpy of reaction = -285.8 kJ/mol, gibbs free energy of reaction = -237.1 kJ/mol, the calculator gives maximum thermodynamic efficiency ≈ 82.96011 %; heat not convertible to work ≈ -48.7 kJ/mol.
Frequently asked questions
What is the fuel cell thermodynamic efficiency calculator used for?
Find the maximum efficiency of a fuel cell from the Gibbs energy and enthalpy of its reaction. It helps with questions such as “fuel cell efficiency”, “hydrogen fuel cell maximum efficiency”, “ΔG over ΔH”.
What is the formula for the fuel cell thermodynamic efficiency calculation?
Maximum thermodynamic efficiency (%) = dG / dH × 100. Heat not convertible to work (kJ/mol) = dH-dG. Here dH is enthalpy of reaction (kJ/mol), dG is gibbs free energy of reaction (kJ/mol).
What inputs do I need for the fuel cell thermodynamic efficiency calculator?
You need enthalpy of reaction in kJ/mol, gibbs free energy of reaction in kJ/mol. Each field is pre-filled with a typical example so you can see how the result responds as you edit the numbers.
How do I use the fuel cell thermodynamic efficiency calculator?
Type values into the input fields. Results and the chart update instantly. Use Reset to restore the example values, Copy results to paste them elsewhere, or Share to copy a link that preserves your inputs.
Is the fuel cell thermodynamic efficiency result exact?
Calculations use standard formulas and double-precision arithmetic, then display about seven significant figures. Real-world measurements carry uncertainty, so treat results as estimates unless your inputs are exact.