CNG vs. LPG

Compressed Natural Gas vs. Liquefied Petroleum Gas. The difference between the two, and some good general knowledge

1. CNG vs. LPG Joe Martino

2. Introduction / History LPG has been used since the 1940’s in automobiles CNG has been used since the 1930’s in automobiles A diesel locomotive was retrofitted with CNG around 2002 LPG’s largest use is in cooking and heating CNG is mostly compressed methane LPG is propane and butane LPG is replacing chlorofluorocarbons as propellants in aerosols

3. CNG / LNG Operation

4. LPG Operation

5. Pros and Cons of CNG Pro Better emissions than petrol Lower cost per mile Eco-friendly Efficient combustion Lighter than air Less oil contamination Con High pressure Comes through pipeline Measured in KG Slow fill time Expensive conversion Hard to find refueling station Lower power than gasoline

6. Pros and Cons of LPG Pro Better emissions than gasoline Low pressure Easy to find refueling station Quick refueling Good power production Low oil contamination Efficient combustion Very Eco-Friendly Con Heavier than air Hotter combustion Less power than gasoline Requires heavy duty cooling system Requires special fuel system

7. Similarities Between CNG and LPG High octane ratings More fuel consumption Lower emissions Efficient combustion Low oil contamintation Eco-friendly Conversion cost

8. Performance Applications Similar octane ratings Bi-fuel Low cost Already used for many diesel engines to increase boost Temperature decreases as pressure drops Increased efficiency and power when used in combination with other fuels