Introducing the Total Customer Imbalance Information

Tuesday, October 25, 2005

In an effort to share pipeline operation information, CGT provides the graphical System Inventory Status chart that illustrates whether the pipeline inventory is approaching its safe operating limits. This is the classic indicator of whether an Operational Flow Order (OFO) may be on the horizon. Now, please welcome the Total Customer Imbalance, which complements the System Inventory Status information.

What is the Total Customer Imbalance?

The Total Customer Imbalance is the sum of the daily imbalances for core and noncore customers including Electric Generation. This measure is valuable because the Total Customer Imbalance indicates the extent to which the system is being packed or drafted by customers. Large customer imbalances are frequently a precursor to OFOs. The Total Customer Imbalance volume can be positive, indicating system packing (supply is greater than demand) or it may be negative, indicating drafting (demand is greater than supply).

Utilizing the Total Customer Imbalance

Similiar to the System Inventory Status, the The Total Customer Imbalance may change throughout the day with each of the operating plans. If the Total Customer Imbalance shows a trend of overdelivery and the pipeline inventory is approaching the upper pipeline inventory limit, the chances of an OFO increases. Any continued overdelivery that is greater than the pipeline balancing injection of 75 MMcf may move the system closer to the upper inventory limit, and trigger the calling of an OFO.

Large customer imbalances can impact the system to the point where it may be necessary to hold nominations to prior cycle volumes. The Total Customer Imbalance may help explain why an "unexpected" OFO or nomination holding event was required.

The Total Customer Imbalance can be found on the Pipe Ranger PG&E Supply and Demand Forecast page, Recent Supply and Demand Data page, and on the Supply and Demand Data Archives page.