Imbalance

Signaling a rise in linepack, Westcoast changed its imbalance tolerance range Sunday to 5% pack and 15% draft.

A week after changing its imbalance tolerance range to 20% pack and zero draft to combat falling linepack (see Daily GPI, March 23), Westcoast had the normal range of 10% pack and 10% draft in effect again Monday.

Reflecting a drop in linepack, Westcoast posted daily imbalance tolerances of 15% pack and 5% draft for Monday. Last Tuesday the tolerances had been changed to zero pack and 20% draft (see Daily GPI, March 4).

Pacific Gas & Electric set a stringent imbalance tolerance of zero in declaring a systemwide Stage 2 high-inventory OFO for Wednesday. Penalties are $1/Dth. The utility’s “System Inventory Status” section of its Pipe Ranger bulletin board projected Tuesday that linepack would be above maximum target levels from Wednesday through Sept. 19.

Florida Gas Transmission kept an Overage Alert Day notice with 20% imbalance tolerance in place through Saturday, then lifted it Sunday. A new OAD notice with 15% tolerance for negative daily imbalances was issued for the pipeline’s market area Monday.

Pacific Gas & Electric did not extend a high-inventory OFO with zero imbalance tolerance beyond Saturday.

Pacific Gas & Electric declared a systemwide Stage 2 high-inventory OFO for Friday. It carried a relatively loose positive imbalance tolerance of 9% and penalties of $1/Dth.

Florida Gas Transmission loosened the negative imbalance tolerance from 15% to 20% in continuing Friday’s Overage Alert Day notice through Saturday, then lifted the notice Sunday.

Pacific Gas & Electric declared a systemwide Stage 2 high-inventory OFO for Friday. It carried penalties of $1/Dth for exceeding a positive daily imbalance tolerance of 4%.