Natural gas volumes or Btu Factors (Heating Values) can be converted from one pressure base to another pressure base using the following formulas or conversion factors shown in Table 1 and Table 2 below.
General Rule: An MMBtu is an MMBtu regardless of the pressure base. Accordingly, as the pressure base increases, the natural gas volume (Mcf) decreases and the Btu Factor increases.
Formula Definitions:
PF = pressure base at which volume or Btu factor is being converted from
PT = pressure base at which volume or Btu factor is being converted to
Volume Conversion Formula:
Mcf@PF times (PF divided by PT) = Mcf@PT
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TABLE 1 - Conversion factors for converting Mcf volume from one pressure base to a different pressure base.
|
|
From Pressure Base of
|
To Pressure Base of
|
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14.65
|
14.696
|
14.73
|
15.025
|
|
14.65
|
1.000000
|
0.996870
|
0.994569
|
0.975042
|
|
14.696
|
1.003140
|
1.000000
|
0.997692
|
0.978103
|
|
14.73
|
1.005461
|
1.002314
|
1.000000
|
0.980366
|
|
15.025
|
1.025597
|
1.022387
|
1.020027
|
1.000000
|
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Volume Conversion Calculation Examples:
1000Mcf @14.65 times (14.65 divided by 14.73) = 995Mcf @14.73
1000Mcf @14.65 times .994569 = 995 Mcf @14.73
Heating Value Conversion Formula:
Btu@PF times (PT divided by PF) = Btu@PT
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TABLE 2 - Conversion factors for converting heating values (Btu factors) from one pressure base to a different pressure base. Note: the factors in Table 2 are the inverse (or reciprocals) of the factors shown in Table 1 (i.e. 1 divided by the Table 1 factor equals the Table 2 factor).
|
|
From Pressure Base of
|
To Pressure Base of
|
|
14.65
|
14.696
|
14.73
|
15.025
|
|
14.65
|
1.000000
|
1.003140
|
1.005461
|
1.025597
|
|
14.696
|
0.996870
|
1.000000
|
1.002314
|
1.022387
|
|
14.73
|
0.994569
|
0.997692
|
1.000000
|
1.020027
|
|
15.025
|
0.975042
|
0.978103
|
0.980366
|
1.000000
|
|
Heating Value Calculation Examples:
1010Btu/Cf @14.65 times (14.73 divided by 14.65) = 1016Btu/Cf @14.73
1010Btu/Cf @14.65 times 1.005461 = 1016Btu/Cf @14.73