Compressed Natural Gas
One GGE of natural gas is 126.67 cubic feet (3.587 m3) at standard conditions. This volume of natural gas has the same energy content as one US gallon of gasoline (based on lower heating values: 900 BTU/cu ft of natural gas and 115,000 BTU/gal of gasoline).
One GGE of CNG pressurized at 2,400 psi (17 MPa) is 0.77 cubic foot (21.8 liters). This volume of CNG at 2,400 psi has the same energy content as one US gallon of gasoline (based on lower heating values: 148,144 BTU/cu ft of CNG and 115,000 BTU/gal of gasoline. Using Boyle's Law, the equivalent GGE at 3,600 psi (25 MPa) is 0.51 cubic foot (14.4 L or 3.82 actual US gal).
The National Conference of Weights & Measurements (NCWM) has developed a standard unit of measurement for compressed natural gas, defined in the NIST Handbook 44 Appendix D as follows: "1 Gasoline gallon equivalent (GGE) means 2.567 kg (5.660 lb) of natural gas."
When consumers refuel their CNG vehicles in the USA, the CNG is usually measured and sold in GGE units. This is fairly helpful as a comparison to gallons of gasoline.
Read more about this topic: Gasoline Gallon Equivalent
Famous quotes containing the words compressed, natural and/or gas:
“Give up the belief that mind is, even temporarily, compressed within the skull, and you will quickly become more manly or womanly. You will understand yourself and your Maker better than before.”
—Mary Baker Eddy (1821–1910)
“The image cannot be dispossessed of a primordial freshness, which idea can never claim. An idea is derivative and tamed. The image is in the natural or wild state, and it has to be discovered there, not put there, obeying its own law and none of ours. We think we can lay hold of image and take it captive, but the docile captive is not the real image but only the idea, which is the image with its character beaten out of it.”
—John Crowe Ransom (1888–1974)
“When we can drain the Ocean into mill-ponds, and bottle up the Force of Gravity, to be sold by retail, in gas jars; then may we hope to comprehend the infinitudes of man’s soul under formulas of Profit and Loss; and rule over this too, as over a patent engine, by checks, and valves, and balances.”
—Thomas Carlyle (1795–1881)