Kerosene is frequently blended with diesel fuel to improve winter cold flow operability. Kerosene-blended diesel fuel is a combination of  #1 diesel fuel (kerosene) and #2 diesel fuel. The ratio of diesel fuel to kerosene is typically found in the range of 80/20, 70/30, 60/40, or 50/50. 


The primary reason for blending diesel fuel with kerosene is to improve cold flow operability. Kerosene has a better cold filter plugging point (CFPP) than diesel fuel, which means it can be successfully passed through a filter at a lower temperature than untreated diesel fuel.


Kerosene blending is not a cost-effective method of achieving the desired cold flow operability. In most cases, treating the fuel with a cold flow improver additive is the most cost-effective solution. To calculate the cost of kerosene blending versus using a cold flow improver additive, perform the following analysis:

1. Determine cost difference between kerosene and diesel fuel ($/gallon)
2. Determine the blending ratio (70:30, 50:50)
3. Calculate the amount of kerosene needed (Gallons)    
4. Calculate cost difference ($)
5. Determine per gallon cost of additive ($/Gallon)
6. Calculate net savings (kerosene cost - additive cost)


1. Assume kerosene costs $0.10 more per gallon than diesel fuel
2. Assume 50/50 blend at 50,000 gallons
3. Kerosene needed equals 25,000 gallons
4. Cost difference equals $2,500 ($0.10 x 25,000)
5. Assume per gallon cost of additive is $0.02. Cost of additive to treat 50,000 gallons equals $1,000 ($0.02 x 50,000).
6. Net Savings equals $1,500 ($2,500 - $1,000)!


The net savings equals $1,500 or $0.03 per gallon using a cold flow improver additive instead of a 50/50 kerosene blend.


Kerosene contains less energy (measured in British Thermal Units or BTUs) than diesel fuel which results in decreased engine power and fuel economy. Kerosene has an average BTU content of approximately 133,500 per gallon and diesel fuel has an average BTU content of approximately 139,500 per gallon. 

When using a 50/50 kerosene blend, BTU content is approximately 136,500 or two percent less than diesel fuel. The resulting fuel economy and power loss is also about two percent.  

Kerosene provides only a small amount of increased cold flow operability. Kerosene will decrease the CFPP by 2ºF for every 10% kerosene used. Diesel fuel additives, on the other hand, will reduce the CFPP by as much as 35°F- 45°F. 

Kerosene contains less lubricity than diesel fuel. Diesel fuel lubricity is a major concern because of Ultra Low Sulfur Diesel (ULSD). ULSD contains significantly less lubricity than Low Sulfur Diesel (LSD). As a result, metal components in the fuel system, including fuel pumps and injectors, are susceptible to premature failure. Many diesel fuel additives will actually increase overall fuel system lubricity.

Kerosene contains less cetane than diesel fuel. Cetane is the most universally accepted measure of diesel fuel ignition quality. Proper ignition during the combustion cycle is essential for optimum operation, economics, and durability. Insufficient cetane levels lead to hard starting, longer warm-ups, and heavy white smoke. 


Increased Cost
Decreased Engine Power
Decreased Fuel Economy
Inadequate Cold Flow Operability
Decreased Lubricity
Decreased Cetane


Diesel fuel additives are the most economical and effective means of improving winter cold flow operability. It costs less to treat a gallon of diesel fuel with diesel fuel additives than it does with kerosene. Blending a diesel fuel additive with diesel fuel will improve cold flow operability without decreasing engine power and fuel economy. The advantages of using diesel fuel additives include:

Increased engine power and fuel economy
Increased winter fuel operability
Increased fuel system lubricity
Increased cetane

E-ZOIL manufacturers several diesel fuel additives formulated to achieve these advantages including DIESEL AID, DIESEL AID + CETANE, ARTIC POWER, ARTIC FLO, and CARBON CRUSHER.   

 NOTE: Users of kerosene blended diesel fuel should note that E-ZOIL diesel fuel additives are compatible with kerosene blended diesel fuel.