Heat of Combustion Calculator
Calculate the higher heating value (HHV) for fuel combustion reactions
Calculate Heat of Combustion
Energy released without considering water vapor condensation
Standard value for water is 2.257 MJ/kg at 25°C
Number of water molecules produced in combustion
Amount of fuel that undergoes combustion
Combustion Results
Formula: Hc = LHV + (Hv × nH₂O/nfuel)
Calculation: 0.00 + (2.257 × 0/1) = 0.00 MJ/kg
Description: Higher heating value includes energy from water vapor condensation
Example Combustion Reactions
Methane Combustion
CH₄ + 2O₂ → CO₂ + 2H₂O
Complete combustion of methane produces 2 moles of water per mole of fuel
Ethanol Combustion
C₂H₅OH + 3O₂ → 2CO₂ + 3H₂O
Ethanol combustion produces 3 moles of water per mole of fuel
Propane Combustion
C₃H₈ + 5O₂ → 3CO₂ + 4H₂O
Propane combustion produces 4 moles of water per mole of fuel
Energy Values Reference
Common Fuels LHV
Combustion Types
Understanding Heat of Combustion
What is Heat of Combustion?
Heat of combustion (also called higher heating value or HHV) is the amount of energy released when a fuel undergoes complete combustion with oxygen. It includes the energy recovered from condensing the water vapor produced during combustion.
Key Components
- •Lower Heating Value (LHV): Energy without water vapor condensation
- •Heat of Vaporization: Energy required to vaporize water
- •Stoichiometry: Molar ratios of reactants and products
The Combustion Formula
Heat of Combustion
Hc = LHV + (Hv × nH₂O/nfuel)
Hc = Heat of combustion (higher heating value)
LHV = Lower heating value
Hv = Heat of vaporization of water
nH₂O = Moles of water produced
nfuel = Moles of fuel combusted
General Combustion
CxHy + O₂ → xCO₂ + (y/2)H₂O
Hydrocarbon fuel combustion with oxygen
Applications and Importance
Energy Production
Power plants and heating systems use HHV to calculate energy output and efficiency.
Fuel Comparison
Compare different fuels based on their energy content per unit mass or volume.
Engine Design
Automotive and aerospace engineers use HHV for engine performance calculations.