ERCOT reveals violations of pricing, disclosure rules in new filing
- The Electric Reliability Council of Texas (ERCOT) informed state regulators of several violations earlier this week, including a failure to post price-quantity offer pairs for ancillary services for intervals in which the Market Clearing Price for Capacity (MCPC) exceeded an event trigger.
- ERCOT also informed the Public Utilities Commission of an "inadvertent disclosure of certain generator interconnection information," along with an "inconsistency" between logic used in Security Constrained Economic Dispatch (SCED) and other protocols.
- Platts spoke with a trade analyst at Aspire Commodities, who called the grid operator's admission "troubling." Some of the violations date back several years, casting doubt on some price formation on the Texas grid.
ERCOT has discovered several inconsistencies or errors, and in its filing told state regulators that it "takes its responsibilities under the commission's rules and the ERCOT protocols seriously ... [and] is prepared to discuss these matters in further detail at the commission's request."
The grid operator said it had "recently discovered an inconsistency between the logic used in its systems for the creation of proxy energy offer curves for SCED and ERCOT Protocols section 126.96.36.199(4), which governs the creation of proxy energy offer curves for certain resources and scenarios."
The protocols require 1 MW be added or subtracted from certain values to create proxy energy offer curves. However, ERCOT officials say the parameter was programed for SCED at 0.01 MW, rather than 1 MW since Dec. 1, 2010, the date of nodal market implementation.
"This inconsistency impacted proxy energy offer curves for the small group of resources referenced in Protocols sections 188.8.131.52(4)(a)-(d), which are primarily intermittent renewable resources and dynamically scheduled resources that do not submit their own energy offer curves," ERCOT explained.
The grid operator said it has corrected the discrepancy in its systems.
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