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Natural Gas

Measurement Conversions

Commercial Energy Services

Notes for Natural Gas Measurement Conversions Table

For more information and technical assistance, please contact Bill Hennessey,Transportation and Marketing Services, (604) 592-7916.

This information herein is a guide only. BC Gas is not responsible for the accuracy and cannot accept any legal responsibility for any errors that may be made.

Selected SI Prefixes(Also apply to earlier metric systems)

PREFIX SYMBOL MULTIPLYING FACTOR

exa E 1 000 000 000 000 000 000 = 1018

peta P 1 000 000 000 000 000 = 1015

tera T 1 000 000 000 000 = 1012

giga G 1 000 000 000 = 10 9

mega M 1 000 000 = 106

kilo k 1 000 = 103

Gas Heating Value in BC

• Gas heating value in BC varies with thegeographic location. It varies from a higherheating value (HHV) of 39.21 MJ/m3 (1052.8Btu/cf) to 37.55 MJ/m3 (1008.2 Btu/cf).

Fuel Requirement Calculations

• Keep in mind the difference between LHV andHHV in making fuel calculations:It is general practice in the industry to calculategas turbine and gas engine performance on thebasis of the lower heating value (LHV) of the fuelto be burned whereas typical heating applicationsand purchase contracts are figured on the basis of higher heating value (HHV).

LHF is generally used in power generationbecause the latent heating value of the watervapour cannot be captured. However, condensing appliances (boilers, furnaces) can capture and usethe latent heating value of water vapour.

In practical terms, you must increase the LHV based fuel consumption by a factor of 1.11(approximate for natural gas).

General Reference Heating Values

• Frequently, for an order of magnitude calculationsand comparison of various energy sources thefollowing higher heating values (HHV) are usedfor natural gas:• 1000 Btu/cf = 37.2 MJ/m3 (Canada and USA)• 1032 Btu/cf = 38.4 MJ/m3 (USA)• 1034 Btu/cf = 38.5 MJ/m3 (Canada)

Heating Value Definition

• Higher HeatingValue (HHV)Gross Heating Value (GHV)Gross Calorific Value (GCV)Total Calorific Value (TCV)These terms are equivalents. Needless to say however, that HHV is a term in the metric SI andis used more frequently. The HHV can be definedas the total heat obtained from combustion of a specified amount of fuel and its stoichiometrically 

correct amount of air, both being at 60˚F whencombustion starts, and the combustion productsbeing cooled to 60˚F before heat release ismeasured. By contrast see lower or net heating value. Gas is sold on the higher heating value(HHV) basis.

• Lower Heating Value (LHV)Net Heating Value (NHV)Net Calorific Value (NCV)Lower (net) heating value is the higher (gross)heating value minus the latent heat of vaporization of the water vapour formed by thecombustion of the hydrogen in the fuel. A “rule of thumb” for natural gas is HHV = LHV x 1.11.

THE TERMS BILLION, TRILLION shall not beused in SI because of ambiguity in their meaning.

TERM MEANING

Canada MostOther Countriesand USA Including UK & Germany

Million 106 106

Billion 109 1012

Trillion 1012 1018

Quadrillion 1015 1024

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NATURAL GAS MEASUREMENT CONVERSIONS

Quantity of natural gas is measured inenergy units or in volume units. BC Gasbilling is in energy units — gigajoules.Because the actual gas volume changes with gas pressure and temperature, thevolume measurements are always covertedto “Standard Gas Conditions”.

Note: All Btu and kcal are International Table units.1 kcal = 4.187 kJ = 4.187 x 10 -3 MJ = 1.163 x 10-3 kW.h = 3.968 Btu = 4.187 x 10-6 GJ1 Dth = decatherm = 10 therms = 106 Btu = MMBtu = 1.055 GJ1 quad = quadrillion Btu = 1015 Btu = 1.055 x 109 GJ = 1.055 x 103 PJ = 1.055 EJ1 Tcf = trillion cubic feet = thousand Bcf = 109 Mcf = 28.328 x 109m3 (*)

1 toe = tonne of oil equivalent = 107 kcal = 41.87 GJ1 Mtoe = 106 toe = 1013 kcal = 41.87 x 106 GJ = 41.87 PJ1 Gtoe = 109 toe = 1016 kcal = 41.87 x 109 GJ = 41.87 EJ1 barrel of crude oil = 5.8 x 106 Btu = 5.8 MMBtu = 6.119 GJ

** 38.6 MJ/m3 = 1036.4 Btu/cf is usedfor the volumetric conversions below. Seecomments on previous page. Not for usein billing calculations.

*Metric Standard gas conditions 101.325 kilopascals and 15˚C (dry) (14.696 psia and59˚F)*Imperial Standard gas conditions 14.73 psia and 60˚F (dry) (101.560 kilopascals and15.56˚C)1 m3 (@ metric std) = 35.315 x 0.9996 = 35.301 cf (@ Imperial std)

The difference resulting from different standard conditions is quite small and for

approximate calculations can be neglected.

ENERGY UNITS USED FOR NATURAL GAS MEASUREMENT *STANDARD VOLUME UNITS FOR BC**

Metric-SI Metric-SI Metric-SI Metric-SI Metric-SI Imperial Imperial Imperial Metric-SI Imperial Imperial Imperial

megajoule gigajoule terajoule petajoule kilowatthour thousand Btu therm million Btu cubic metre thousand cu ft million cu ft billion cu ft

106 J 109 J 1012 J 1015 J 103 W.h. 103 Btu 105 Btu 106 Btu 103 L 103 cf 106 cf 109 cf 

MJ GJ TJ PJ kW.h MBtu therm MMBtu M3 Mcf MMcf Bcf  

MJ = 1 = 10-3 = 10-6 = 10-9 = 0.2778 = 0.9478 = 9478 x 10-3 = 9.478 x 10-6 = 25.91 x 10-3 = 914.54 x 10 -6 = 914.54 x 10-9 = 914.54 x 10-12

GJ = 103 1 10-3 10-6 277.78 947.82 9.4782 0.9478 25.907 0.9145 914.54 x 10-6 914.54 x 10 -9

TJ = 106 103 1 10-3 277.8 x 103 947.8 x 103 9.478 x 103 947.82 25.91 x 103 914.54 0.9145 914.54 x 10-6

PJ = 109 106 103 1 277.8 x 106 947.8 x 106 9.478 x 106 947.82 x 103 25.91 x 106 914.54 x 103 914.545 0.9145

kW.h = 3.6 3.6 x 10 -3 3.6 x 10 -6 3.6 x 10 -9 1 3.4121 34.12 x 10-3 3.412 x 10 -3 93.26 x 10 -3 3.292 x 10-3 3.292 x 10 -6 3.292 x 10 -9

MBtu = 1.055 1.055 x 10-3 1.055 x 10 -6 1.055 x 10 -9 0.2931 1 10-2 10-3 27.33 x 10 -3 964.9 x 10 -6 964.9 x 10 -9 964.9 x 10 -12

therm = 105.5 0.1055 105.5 x 10 -6 105.5 x 10-9 29.307 100 1 0.1 2.733 96.49 x 10-3 96.49 x 10 -6 96.49 x 10 -9

MMBtu = 1.055 x 103 1.055 1.055 x 10-3 1.055 x 10 -6 293.07 103 10 1 27.33 0.9649 964.9 x 10-6 964.9 x 10 -9

m3 = 38.6 38.6 x 10 -3 38.6 x 10 -6 38.6 x 10 -9 10.72 36.586 0.3659 36.59 x 10-3 1 35.3 x 10 -3 35.3 x 10 -6 35.3 x 10 -9

Mcf  = 1.093 x 103 1.0935 1.093 x 10-3 1.093 x 10 -6 303.74 1036.4 10.364 1.0364 28.328 1 10-3 10-6

MMcf  = 1.093 x 106 1.093 x 103 1.0935 1.093 x 10-3 303.7 x 103 1.036 x 106 10.36 x 103 1.036 x 103 28.33 x 103 103 1 10-3

Bcf  = 1.093 x 109 1.093 x 106 1.0935 x 103 1.0935 303.7 x 106 1.036 x 109 10.36 x 106 1.036 x 106 28.33 x 106 106 103 1

multiply

to obtain