Eastern, WECC, ERCOT and Hydro Quebec

September, 2012 Frequency Events’ Data Summary

and Corresponding Frequency Plots

For: NERC Resources Subcommittee and Frequency Working Group

Prepare by: CERTS and Electric Power Group

Date: October 15, 2012

NERC INTERCONNECTIONS SEPTEMBER, 2012 FREQUENCY EVENTS – SUMMARY DATAEASTERN

WESTERN

ERCOT

HYDRO QUEBEC

Frequency Response can be calculated from NERC SA Actual MW Loss divided by 10* B-A. The results will be in MW/0.1 HZ

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EASTERN INTERCONNECTION

SEPTEMBER, 2012 FREQUENCY EVENTS

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WESTERN INTERCONNECTION

SEPTEMBER, 2012 FREQUENCY EVENTS

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ERCOT INTERCONNECTION

SEPTEMBER, 2012 FREQUENCY EVENTS

HQ INTERCONNECTION

SEPTEMBER, 2012 FREQUENCY EVENTS

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