[SkyDancer]

Okay - so I guess LNG has more power than propane (which I forgot to mention).

[thackney]

Propane is liquefied under reasonable pressure, 50~250 psi depending on temperature.

LNG requires great cooling to liquefy, -260°F.

Both are burned in the gas state; they have to be vaporized for use.

So comparisons can be a little misleading, unless you are only concerned with storage space.

One gallon diesel = 139,000 Btu

One gallon gasoline = 125,000 Btu

One gallon LPG (propane) = 91,000 Btu

One gallon LNG = 82,650 Btu

However LNG weighs less.

1 gallon LNG = 3.5 lbs

1 gallon LPG = 4.2 lbs

so you get more energy per pound with LNG

LNG = 21,700 BTU/lb

LPG = 23,600 BTU/lb