Natural Gas Compressor Stations on the Interstate Pipeline Network: Developments Since 1996
November 7, 2007
This special report looks at the use of natural gas pipeline compressor stations on the interstate natural gas pipeline network that serves the lower 48 States. It examines the compression facilities added over the past 10 years and how the expansions have supported pipeline capacity growth intended to meet the increasing demand for natural gas. Questions or comments on the contents of this article may be directed to James Tobin at James.Tobin@eia.doe.gov or (202) 586-4835.
The U.S. interstate natural gas pipeline network relies on more than 1,200 natural gas compressor stations to maintain the continuous flow of natural gas between supply area and consumers. Compressor stations are “pumping” facilities that advance the flow of natural gas. They are usually situated between 50 and 100 miles apart along the length of a natural gas pipeline system and are designed to operate on a nonstop basis. The average station is capable of moving about 700 million cubic feet (MMcf) of natural gas per day, while the largest can move as much as 4.6 billion cubic feet (Bcf) per day.
Between 1996 and 2006, the number of natural gas pipeline compressor stations attached to the interstate mainline natural gas pipeline grid increased significantly. In 1996 there were approximately 1,047 mainline compressor stations, with installed horsepower of about 13.4 million and a combined throughput capability of approximately 743 billion cubic feet per day. By 2006, these figures had grown to 1,201 mainline compressor stations, 16.9 million installed horsepower, and a throughput capability of 881 Bcf per day). This expansion represented a 26-percent increase in installed horsepower and a 19-percent increase in throughput capacity during the period.
This growth was not driven solely by an increase in overall natural gas production and consumption during the period. In fact, compared with 1996 levels, both natural gas production and consumption in the United States in 2006 are slightly lower, although both measures increased somewhat (about a 4-percent increase by 2001 in production) during the interim. Rather, a series of factors, reflecting the changing character of the U.S. natural gas industry, influenced this expansion in mainline compression facilities:
- New domestic production sources were developed in areas that required installation of new natural gas pipeline systems or expansion of existing ones.
- As domestic natural gas production reached a plateau during the 1990s, demand increased for Canadian natural gas supplies and new pipelines to transport them were created.
- Major growth in the number of large-volume natural-gas-fired electric power generating plants required additional capacity in specific markets.
- Regulatory demands to reduce the environmental footprint of compressor stations increased the scale of station revitalization and retrofits with improved technology.
Meanwhile, the decrease in U.S. natural gas production overall and the decrease in natural gas supplies flowing from declining production areas contributed to deactivating 22 mainline compressor stations and the downsizing of 45 more stations during the period. The loss in installed horsepower and/or throughput capacity from deactivation, however, was more than offset by the installation of more than 176 new compressor stations, and upgrades to over 250 other stations, throughout the national network.