During one year I have recorded following values
- Weight of water boiled on kitchen scales
- Amount of gas used on gas meter
- Time until the kettle whistle goes off
Gas usage | Time spent |
---|---|
For simplicity I consider in this example that natural gas is 100% methane (which is usually only around 85% methane).
In this example I consider following values:
1.6 kg
of water (~1.6L)0.045 m3
of gas used- Molar enthalpy of combustion of methane :
890.307
kJ / mol
Calculations:
- Amount of substance of gas :
n = (V * ρ) / M = (0.045 * 0.8 * 1000) / 16.043 = 2.243 mols
- Energy released :
Q = ∆H * n = 890.307 * 2.243 = 1997.82 kJ
- Energy released per liter :
Q / V = 1997.821604 / 1.6 = 1230.185 kJ / dm3
Energy released compared to electric kettle