Someone asked for the relative energies of natural gas compared to
Gasoline. What I've been able to gather is :
1 cu/ft NG=1028 BTU
1 gal Gasoline=125000 BTU
C. Smith

Those are "sit and burn" BTUs.

In actuality, the efficiency of gasoline as a motor fuel is very low,
while the efficiency of natural gas is very high.  Otherwise, a NG or
propane-fueled car would have pretty much no range or power.  There are
gas-powered Crown Vics in service as police cruisers!

Gasoline must be stable as a liquid, then rapidly broken down and
vaporized before it will burn, so most of a gallon of gas provides no
power.  Natural gas must simply be heated, and a far higher percentage
burns.

Keith W

Well there is still the high BTU per cubic foot of gasoline.
The tank needed for NG is also big and heavy.

Paul Lamar

My Dad was a cop for 30 years. Here in Michigan, we also had police
cruiser that were v-6 diesel NA engines - Oldsmobile's. Very slow. But,
when the automaker offers your department some new style cruiser at a
price you can't turn down, and the maintenance to go along with it, even
High Pressure NG can be an attractive fuel. That Crown Vic was likely
also in Michigan near the Wixom Ford plant where one of few HNG fueling
stations is located.

Here's an interesting story on why fuel cells are not a good idea for
our cars http://www.physorg.com/news85074285.html

-dave