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NG CNG

Posted: Thu May 11, 2006 9:02 pm
by Cole
NG comes to my house now and i have an old CNG pump to fill ur car or truck over night im thinking maybe i should put one of my old gas eaters on CNG i got most of the parts i would just need a fuel ring and some vacum parts
Does any one know how CNG runs compard to propane and or gas just want to know is it worth the time and little bit of money?

Some simple basics

Posted: Fri May 12, 2006 11:19 am
by franz
LPG = 2500 btu's per cubic foot
CNG = 1000 btu's per cubic foot
LPG stored at approx 125-175 psig, depending temperatures, could be much lower or much higher but almost never over 250 psig;
CNG stored at pressures to 3600 psig.
LPG is a pressurized liquefied gas
CNG is a pressurized vapor
LPG tanks are relatively inexpensive, about $400 USD for a 40-gallon tank.
CNG tanks are VERY expensive, about $1000 for an 8-gallon equiv tank.
LPG driving range is about 4 to 5 times as far as the same storage space CNG.
LPG is almost always 80% that of gasoline, sometimes better.
CNG is almost always 60 to 70% that of gasoline.

Be VERY careful of marketing hype claiming GGE. All that does is to change the rating of the fuel into gasoline gallons equivalent. In that respect, CNG would equal that of gasoline.

If you have an old home pump for CNG, they had to be reclocked at the factory every 2000 operational hours, changed to either 3,000 or 4,000 hours, roughly once every 1 to 2 years, depending on usage. These units would fill at the rate of about 115 cubic feet per hour, or about 8 hours for the equivalent of 8 gallons.

Franz

Propane

Posted: Fri May 12, 2006 8:45 pm
by Cole
I think ill stick with the Proapne :P

Re: Some simple basics

Posted: Sun May 14, 2006 3:21 pm
by gabriel1
franz wrote:LPG = 2500 btu's per cubic foot
CNG = 1000 btu's per cubic foot
LPG stored at approx 125-175 psig, depending temperatures, could be much lower or much higher but almost never over 250 psig;
CNG stored at pressures to 3600 psig.
LPG is a pressurized liquefied gas
CNG is a pressurized vapor
LPG tanks are relatively inexpensive, about $100 USD for a 40-gallon tank.
CNG tanks are VERY expensive, about $400 for an 8-gallon equiv tank.
LPG driving range is about 4 to 5 times as far as the same storage space CNG.
LPG is almost always 100% that of gasoline, sometimes better.
CNG is almost always 90% to 95% that of gasoline.

Be VERY careful of marketing hype claiming GGE. All that does is to change the rating of the fuel into gasoline gallons equivalent. In that respect, CNG would equal that of gasoline.

If you have an old home pump for CNG, they had to be reclocked at the factory every 2000 operational hours, changed to either 3,000 or 4,000 hours, roughly once every 1 to 2 years, depending on usage. These units would fill at the rate of about 115 cubic feet per hour, or about 8 hours for the equivalent of 8 gallons.

Franz