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We’ve converted to Therm Billing

Columbia Gas of Maryland improved the way you are billed, as approved by the Maryland Public Service Commission. This change was effective January 30, 2013.

Therm Billing Facts

  • Columbia is aligning the way it bills customers for natural gas with the value of the product (i.e., the energy), and to match the way natural gas is bought and sold in the wholesale market place.
  • This is only a change in the units we use to bill, not a rate increase. Customers were previously billed based on the volume of gas consumed per month, or hundred cubic feet, and will now be billed based on the energy consumed per month, or ”therms” (thm).
  • The volume of gas is measured in Ccf (hundred cubic feet) or Mcf (thousand cubic feet), while the heating or energy value of gas is measured in therms. 
  • Btu (British Thermal Unit) = the amount of energy needed to raise 1 lb. of water 1 degree Fahrenheit.
  • To convert your usage to therms, we multiply the Btu value of the natural gas by the volume of gas (Ccf) consumed that month. For example, if the Btu content is 1.05, your bill calculation will be: 1.05 Btu x 100 Ccf/month = 105 therms.

    Rates must also be converted to therms. To do that, we divide the rate by the Btu factor. For example, if the Btu conversion factor is 1.05, the conversion would be $1.00 / 1.05 = $0.9524.

    After both conversions the resulting bill stays the same. 100 ccf x $1.00 = $100 and after the conversion to therms: 105 therms x $0.9524 = $100.
  • Therm billing maintains fair and equitable bills for customers because bills will be based upon the energy consumed. In addition, the EnergyGuide and Energy Star labels appearing on household gas appliances are based in therms, so this change will make it easier for customers to assess the impact their appliances have on their bills.
  • A good analogy is the purchase of blueberries by the pint.  While two different pint containers are the same size (volume), they don’t necessarily contain the same number of blueberries.  Columbia’s new method of billing in therms is like charging a price per blueberry, rather than a price per pint. Instead of charging two customers the same price for pints of blueberries that contain different amounts, customers will now be charged for precisely the number of blueberries that they purchased, as will every other customer.   
  • By approving this change, the Maryland Public Service Commission is aligning Columbia’s billing units with other natural gas utilities in Maryland who currently bill in therms.

Thank you for being a Columbia Gas of Maryland customer. To learn more about the conversion to therm billing, call 1-866-724-0039.