ABSTRACT

The amount of gas transported for others by Colorado Interstate Gas Company (CIG) more than tripled during the period of 1984 to 1988. The amount of gas sold by CIG fell more than 60% during the same period. Changing roles from merchant of natural gas to transporter has presented a challenge to those who operate and control the pipeline. CIG has responded to the challenge by developing an integrated system of programs to schedule, model and monitor transportation and sales gas. Based on a DEC VAX 111780 computer, the system consists of a transportation gas information management system, a Supervisory Control and Data Acquisition (SCADA) system and Gas Control Planning System.

1 THE CHANGING REGULATORY ENVIRONMENT

May 1985 marked a turning point in the interstate natural gas pipeline business. Up to that point pipelines acted as merchants of gas. Pipelines purchased gas from producers then moved the gas to market and resold it. The Federal Energy Regulatory Commission (FERC) changed all that with its Notice of Proposed Rule making, Order 436. The new regulations have transformed most major interstate gas pipelines into common carriers of natural gas. Colorado Interstate Gas Company has made the transition from merchant to transporter, accepting a blanket open access certificate under FERC Order 500 in 1988. The change of roles has had a dramatic impact on pipeline operations. As a merchant of gas, CIG forecasted all its loads and scheduled all supplies. Gas transported for others was a relatively small segment of the business. Supplies were scheduled to meet loads while taking storage requirements into account. The entire process was under virtually complete control of CIG. Volumes transported by CIG for others tripled from 1984 to 1988. Sales gas has fallen 60% over the same period. Local distribution companies (LDCs) and other traditional sales customers contract with producers to purchase gas, then contract with CIG to transport it. In addition, volumes moving on to interconnecting pipelines for third parties have increased substantially. Much of the control over where gas moves and in what quantities has passed from CIG to the companies contracting for transportation services.

2 TERMINOLOGY

As with any business, gas transportation has its own vernacular. For the sake of clarity a few of the terms most often used should be defined. Receipts are volumes entering the CIG main line. Deliveries are volumes leaving the main line. Shippers are those parties who have contracted for transportation service with CIG. Nominations are specific requests for transportation service which CIG receives from shippers. Transport gas, transportation gas and T&E gas are all the same thing. It is gas which CIG transports but is owned by someone other than CIG.

This content is only available via PDF.
You can access this article if you purchase or spend a download.