What is the heating value of natural gas compared to heating oil and electricity?
To produce the same amount of energy, e.g. 1 GJ, it takes 26.137 m3 of natural gas, 25.773 litres of heating oil and 277.778 kWh of electricity. It is the efficiency of your heating unit that makes the difference in the similar case of heating oil to natural gas, as well as the cost of the resource.