Electric Deregulation in North America
The Federal Energy Regulatory Commission (FERC)'sNERC Tag Versions
NERC Tag 1.x
The earliest NERC Tag application was based on aE-Tag 1.4 and 1.5
Not long after NERC introduced the NERC Tag spreadsheet and packet emailer, NERC concluded that it did not want involvement in any future software development or maintenance. A NERC Tag specification document, version 1.4, was drafted as the next level in energy tagging, the NERC Tag would subsequently also be known as an E-Tag. Data transfer would now occur directly over anE-Tag 1.6
Building on the lessons experienced with E-Tag applications to date, E-Tag 1.6 went into effect in 2000. There were seven variations of E-Tag 1.6, up to E-Tag 1.67 which was in effect until late 2002. Most of the changes in E-Tag 1.6 were of a functional nature and not overly apparent to the users. Under E-Tag 1.6, NERC implemented the "no tag, no flow" rule, where all energy transactions were to be documented with an E-Tag. Accurate system studies of the Eastern Interconnection in order to determine which schedules should be curtailed would only be possible if every transaction was tagged and therefore included in the IDC calculations. Reliability Coordinators in the Eastern Interconnection could access the IDC online and run flow studies based on various operating scenarios with all of the current energy schedules derived from the E-Tags. When an actual contingency occurred, the Reliability Coordinators could identify the constrained transmission line or corridor within the IDC, and the IDC would then identify which E-Tagged schedules should be curtailed in order to ease the loading on the restricted facilities.E-Tag 1.7
NERC's E-Tag 1.7 Specification completely reworked the E-Tag platform from scratch. Some users said that it was so significant that it might have been more appropriate to have called it "E-Tag 2.0". For the first time, Extensible Markup Language (XML) was utilized to format the data transferred between E-Tag applications, finally replacing the base CSV data transfer format based on its ancestral NERC Tag 1.0 spreadsheet/e-mail origins. The TSIN database was expanded to include generation and load points which were matched with PSEs that had rights to schedule them, and also included complex associations that enforced matched sets of PORs and PODs with TPs. E-Tag 1.7 also greatly expanded the time frame flexibility of an E-Tag by allowing extensions and modifications with comprehensive approval processes, layering of multiple OASIS requests for transmission rights, and also fully automated the tag curtailment functions from the IDC so that individual manual tag curtailments were no longer necessary. Shortly after E-Tag 1.7 went online in 2002, the Western Electricity Coordinating Council (WECC) implemented the WECC Unscheduled Flow (USF) Tool, which accomplished a similar automated curtailing capability for theE-Tag 1.8
Five years following the release of E-Tag 1.7, a major update was developed and implemented on December 4, 2007. E-Tag 1.8 cleaned up some long-standing issues not easily addressed with minor revisions to E-Tag 1.7 and brought the E-Tag applications back up to current industry policy standards.Future of E-Tag
OASIS primarily deals with the purchase and availability of transmission from individual transmission providers with a forward-looking time frame, while E-Tag is focused on real-time scheduling and power flow management across multiple systems. Nonetheless, the FERC-derived OASIS applications and NERC-derived E-Tag applications are somewhat duplicative. FERC's plan for the eventual introduction of OASIS Phase 2 envisions a combined platform to post transmission offerings, allow transmission purchases, and facilitate scheduling and flow management, effectively merging the essential functions of E-Tag and OASIS. However, there has been very little activity to move towards OASIS Phase 2 since the introduction of E-Tag 1.7 in 2002, and the future remains unclear. As both systems have increased in complexity over time, the difficulties in merging the two independently evolved systems have likewise also increased.External links