# Energy value of several fuels

The lower heating value (also called energy value, or heat of combustion, or calorific value) is the energy (heat) produced by the combustion of the fuel/material without condensation of the flue gas.

Fuel Energy value [MJ/kg] Energy value [kWh/kg] Density [kg/litre] Energy value [kWh/litre]
Diesel fuel 44,4 12,33 0,835 10,30
Gas (benzine) 43,6 12,11 0,68 8,24
LPG 46,1 12,81 0,52 6,66
Methane 52 14,44 0,656 9,48
Coal (coke) 29,6 8,22 2 16,44
Charcoal (from wood) 31,5 8,75 0,4 3,50
Dry wood 17 4,72 0,8 3,78
Hydrogen 130 36,11 0,0899 3,25
Sugar 17 4,72 1,6 7,56
Peanut butter 24,6 6,83 00.08.00 0,04
Seed oil 37 10,28 0,92 9,46
Butter 30 8,33 0,92 7,67

Wood’s energy value varies maximum 15% between different types of wood.

## Converting the value to other units

To change the unit of measurement, just multiply the starting value by the unit factor FU = 1, to eliminate the unwanted part of the initial unit of measurement. If necessary, use the inverse (1 / FU), which is still 1.

1 = 1 kWh / 3.6 MJ

1 = 4.186 kJ / 1 kcal

## Example 1: We want to convert 10 kWh into Joules

10 kWh * (3.6 MJ / 1 kWh). = 36 MJ.

Note how kWh in the numerator and kWh in the denominator cancel out.

## Example 2: we want to convert 1 kWh into kcal

1 kWh * (3.6 MJ / 1 kWh) * (1000 kJ / 1 MJ) * (1 kcal / 4.186 kJ) = 1 * 3.6 * 1000 * 1 / 4.186 = 860 kcal.

Note how the unit factor also works well for changing the unit prefix (from MJ to kJ in this case).

We just found a new unit factor!

1 = 860 kcal / 1 kWh. (or 1 = 1 kWh / 860 kcal)