Wednesday, September 30, 2009
Following in our August footprints, below are some common cut codes found on California Gas Transmission's 100 and 110 reports. Understanding these common and not-so-common nomination cuts can ease your scheduling research.
Nomination cuts that happen in the Confirm process will help you understand the PG&E volumes confirmed to the interconnect pipelines. Confirm process cuts can be grouped into five primary categories.
Unbalanced Pools
The two most commonly seen cut codes occur when pools are out of balance. These codes are:
There are times when you will receive both ImbPool cuts. This happens when INSIDEtracc is running the Confirm process and balancing pools. If you lose some supply, the system will cut your market based on your destination rankings. If you lose some market, the system will cut your supply based on your source rankings. All pools must be balanced at the end of each Confirm or Schedule process.
Mismatched Nominations
When Buyer and Seller nomination volumes do not match, the result is a "Nom" cut code.
To correct these cuts requires a call to your nominating counterparty to match volumes.
Off-System Deliveries
Nominations made to off-system destinations sometimes result in an "OSD" cut code.
OSD-01 cuts on nominations to Southern California Gas Company at Kern River Station can be corrected by calling SCGC.
OSD-02 cuts on nominations to all other interconnects can be corrected by calling CGT's Gas Scheduling team.
Path Limits
"Path" cuts are not commonly seen, but may occur when the path associated with the nomination Transportation Exhibit is constrained.
A path cut starts with Path-01 nominations where the Transportation Exhibit resides. Then INSIDEtracc must balance the pool by identifying the source gas to the Path-01 nomination. The nominations above the Path-01 cut (source gas) receive a Path-02 cut. The nominations below the Path-01 cut (destination markets) receive a Path-03 cut.
Interconnect Limits
Interconnect cuts, similar to Path cuts, are not commonly seen. However, when aggregate nominations at a given interconnect exceed the physical pipeline capacity, Transportation Exhibits may be constrained.
An Intrcon-03 cut will happen if total customer nominations exceed the posted capacity at an interconnect, thereby restricting the amount of gas that can flow to PG&E. An Intrcon-04 cut will happen if total customer nominations leaving the PG&E system are greater than the total customer nominations coming onto the PG&E system at the following interconnects: Malin, Topock North, Topock South, and Daggett.
Path or Interconnect cuts are applied in the following order:
There are only three cut codes that are applied in the Schedule process, all related to scheduled volumes. They are:
A SchVol-01 cut will happen at the TSA level. This indicates a delivered volume from the upstream pipeline less than the confirmed volume requested.
A SchVol-02 cut is associated with a SchVol-01 cut, and is applied to all the nominations below the TSA level.
A SchVol-03 cut will happen on the Timely schedule process, and only if an upstream pipeline cannot provide scheduled volumes to CGT's Gas Scheduling team at NAESB's designated time.
Another valuable piece of information to master is regarding Source and Destination rankings. Source and Destination rankings reflect a user's preference on which gas should flow in cases where cuts must be made to nominations. Understanding these rankings help puts the whole nomination picture together.
99 is the default ranking in INSIDEtracc and represents a nomination with the lowest ranking. However, a ranking can be any number between 1 (the highest priority) and 99, and multiple nominations can share the same ranking. Any cuts applied to nominations that share rankings will be done pro rata.
The entity in the Source ID field is considered the Seller and controls the Destination ranking. If a pool becomes out of balance due to a supply cut, your destination rankings will determine which market will receive the nominated gas first.
The entity in the Destination ID field is considered the Buyer and controls the Source ranking. If a pool becomes out of balance due to a market cut, your source rankings will determine which source gas will flow to the destination entity first.
When placing your nominations in INSIDEtracc, the system will allow you to input both rankings. Once all the source and destination data is entered, INSIDEtracc determines whether the nomination is tagged as a Seller, Buyer, or Both nomination. At that point, INSIDEtracc either accepts both rankings, if you are both the buyer and seller designated in the nomination, or disallows the ranking that you do not control based on whether you are considered the Source ID entity (Seller) or the Destination ID entity (Buyer).
All Confirm or Schedule process cuts are automatically renominated in the next Confirm cycle, but the cut volumes take on a lower priority. This is because they are tagged as "new" nominations in a later cycle. This explains how a nomination with a high-priority ranking in the Evening cycle will be cut before a nomination with a low-priority ranking from a prior cycle. This process is known as "Last On, First Off" (LOFO). Watch for October's SNL article to provide additional information on the LOFO process.
To preview or print this article as a .pdf file, please navigate to Pipe Ranger's Tools & Services, INSIDEtracc page and click the link for SNL Archives.