NGSA offers natural gas quality recommendations

May 23, 2005
Federal regulators have enough information to act on balanced natural gas quality and interchangeability rules that maintain public safety and allow for supply expansion, the Natural Gas Supply Association (NGSA) said May 16.

Federal regulators have enough information to act on balanced natural gas quality and interchangeability rules that maintain public safety and allow for supply expansion, the Natural Gas Supply Association (NGSA) said May 16.

Gas quality refers to the hydrocarbon content variations in natural gas that could lead to liquids forming in the gas stream. It has been an issue for years.

Interchangeability is the ability of pipeline and distribution systems to accept natural gas with varying heat content or other characteristics. It is of particular importance because of the US’s increased importation of LNG, which may have a thermal content or other characteristics different from gas processed to US pipeline and equipment specification standards. The gas industry has been studying the issue for the past 18 months (OGJ May 16, 2005, p. 33).

At a US Federal Energy Regulatory Commission conference May 17 in Washington, DC, NGSA proposed comprehensive national regulations for gas quality and interchangeability and petitioned FERC for a rulemaking and specific guidelines for inclusion in interstate pipeline tariffs.

“Such regulatory certainty will enable the industry to make efficient capital and supply-development decisions that will bring additional natural gas supplies to the market,” said NGSA Director of Energy Markets Jenny Deegan.

NGSA said its proposed regulations provide FERC with a roadmap to resolve the gas quality and interchangeability issues that “will not only provide for industry-wide establishment of a minimum delivery cricondentherm hydrocarbon dew point (CHDP) and delivery interchangeability specifications, but will also provide a mechanism and decisional parameters designed to deal with problems if they arise.”

NGSA again urged FERC to establish a minimum national CHDP of 15° F., based on industry research. The association encouraged FERC to require interchangeability specifications of 1400 maximum Wobbe Index, 4% inert gas maximums, and 1.5 mole % butanes-plus limit.

NGSA said adoption of these regulations would provide the industry with a technical research-based policy “that preserves the nation’s existing supply flexibility, positions the US within the world energy market in a way that allows it to safely attract imports from a variety of world sources, and encourages the continued economic development of new domestic and imported supply resources.”