Combustion Energy Chart

Heat of combustion for common fuels and foods — per unit mass and per unit volume.

Reference Reference Updated Apr 19, 2026
Reference

Heat of combustion (lower heating value)

Fuel MJ/kg MJ/L Notes
Hydrogen (H₂) 120 0.01 (gas) / 8.5 (liquid) Highest per mass; lowest per volume
Methane (CH₄) 50.0 0.0354 (gas) Natural gas
Propane (C₃H₈) 46.4 23 (liquid) LPG
Butane 45.7 27 (liquid)
Gasoline 43.5 32 Octane mix
Diesel #2 43.0 36
Kerosene / Jet A 43.0 34.7
Ethanol 26.8 21.2
Methanol 19.9 15.8
Coal (bituminous) 24 n/a
Wood (dry) 15–18 n/a
Biodiesel (B100) 37.5 33

Food / biological fuel

Substance MJ/kg kcal / g
Fat / oil 37.7 9
Alcohol 29.7 7
Protein 16.7 4
Carbohydrate 16.7 4

Batteries for comparison

Type MJ/kg
Li-ion (NMC) 0.9
Alkaline 0.5
Lead-acid 0.15

Notes

  • Batteries are ~1 – 2 orders of magnitude less energy-dense than fuels by mass.
  • Engine / generator conversion efficiency is typically 20–40% — usable energy is less than heat of combustion.

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