# Convert gas readings into kWh

Our gas reading for the gas meter is in cubic meter but SP Services will charge us in kWh which is normal. But SP Services does not share the formula on how this is converted to kWh. I am now pushing SP Services to reveal this formula to the customers at large in Singapore. Formula used to convert meter cube to kWh
(meter cube use X volume correction factor X calorific value)/kWh conversion factor

We know the meter cube use through our gas meter and the kWh conversion factor which is 3.6. But we do not know the volume correction factor and calorific value. We need to know the calorific value which is the amount of energy given off when burnt. This value is different for the different gas suppliers in your country.

SP Services has wrote back to me about the conversion of cubic meter into kWh. They used conversion factor of 5.175 to convert cubic meters to units (kWh).

Example:
Meter Reading taken on 18 June 2014: 7203
Meter Reading taken on 20 July 2014: 7323
Difference in readings: 120
Usage in kWh: 120 X 5.175 = 621kWh

Now, you should know the amount of cubic meter that your household is using for your pipe gas from the SP Services Bill. We also help customers to analyse their energy bills and also how to reduce them in your home.

## One thought on “Convert gas readings into kWh”

1. Mr Leong says:

Hey Richard, thank you for providing us with insights on calculating the energy consumption (kWh) via the gas meter. The formula that you’ve provided may not be universal and it depends on the gas meter that was being used. For example, the gas meter that you’re using (the picture attached in your blog post) gives the following conversion:
1 Unit on your meter reading = 3412 BTU = 1 kWh
This goes to say that your meter reading is exactly in the units of kWh, which SP Services use to calculate the tariffs required to pay for a particular month.

The correct calculation should be then,

Meter Reading taken on 18 June 2014: 7203
Meter Reading taken on 20 July 2014: 7323
Difference in readings: 120 units
Usage in kWh: 120 kWh
Cost of gas: 120 kWh * tariffs (\$0.1807/kWh) = \$21.68

Assuming we’re using the calculation that you’ve provided,

Meter Reading taken on 18 June 2014: 7203
Meter Reading taken on 20 July 2014: 7323
Difference in readings: 120
Usage in kWh: 120 X 5.175 = 621kWh
Cost of gas: 621 kWh * \$0.1807/kWh = \$112.21

The energy that you’ve used for gas can be used to run approximately 170 units of air-conditioning systems simultaneously for one hour.

Notably, some gas meters are in cubic decimeter (dm3), while some are in cubic meters (m3). It is therefore important to first identify the units on the gas meter before undertaking any calculations.

I’ve attached a link to the specifications of natural gas used in our homes by City Gas. You may refer to the appendix for more technical details.