"Paul M. Eldridge" wrote in message
...
Hi Edwin,

Were you thinking of "compressed" natural gas or CNG, as opposed to
"liquid" natural gas (LNG)?

CNG requires a much larger volume of storage and very high pressures
-- I believe something in the range of 3000 to 4000 pounds per sq.
inch. It might work OK for vehicles where on-board storage
requirements are relatively modest, but for higher volume residential
applications, it isn't likely to work all that well.

Yes, CNG is the one generally use., but according to this, both can be used.
http://www.eere.energy.gov/afdc/altf...tural_gas.html

Seems like CNG is the cost effective method.