Consideration of practical replacements for gas such as coal, heavy fuel oil, middle distillates, LPG and vice versa.

Fuels considered most practical replacements for gas include coal, heavy fuel oils, middle distillates (such as kerosene type turbo fuel and burner fuel oils) and liquefied petroleum gas (LPG).

To compare relative costs of fuels, the quoted prices normally are converted to the price per million British Thermal Units (BTU). With HHV being the higher (gross) heating value of the fuel, the following equations may be used:

Natural Gas

Cents/million BTU = (cents/Mcf * 106) / (HHV * 1000)


Cents/million BTU = (dollars/ton * 100 * 106) / (HHV * pounds/ton)

Heavy Fuel Oils

Cents/million BTU = (dollars/barrel * 100 * 106) / (HHV * gallons/barrel)

Middle Distillates and LPG

Cents/million BTU = (cents/gallon * 106) / HHV

The approximate heat contents (HHV) of the fuels are as follows:


Anthracite: 13,900 Btu/pound
Bituminous: 14,000 Btu/pound
Sub-bituminous: 12,600 Btu/pound
Lignite: 11,000 Btu/pound

Heavy fuel oils and middle distillates

Kerosine: 134,000 Btu/gallon
No.2 burner fuel oil: 140,000 Btu/gallon
No.4 heavy fuel oil: 144,000 Btu/gallon
No.5 heavy fuel oil: 150,000 Btu/gallon
No.6 heavy fuel oil, 2.7% sulfur: 152,000 Btu/gallon
No.6 heavy fuel oil, 0.3% sulfur: 143,000 Btu/gallon


Natural: 1,000 Btu/ft3
Liquefied butane: 103,300 Btu/ft3
Liquefied propane: 91,600 Btu/ft3

characteristics of fuel oils.JPG