Questions for the Texas Legislative Hearings on Winter Blackouts
Are there any early indications of common mode failure causing generator outages?
We know that a substantial amount of generation capacity (greater than 45,000 MW) was offline during the outages. While different plants undoubtedly failed for different reasons, there were definitely common problems that took multiple plants offline. Identifying and quantifying the specific causes of the outages is key to determining where the vulnerabilities are in the current system. How much of the outages was due to a lack of fuel supply? Were there any transmission outages or constraints limiting generation supply? Were icy or impassable roads a factor limiting generator availability?
When will details regarding the outaged units, and the causes of the outages, be made public?
Answering the previous questions will require information that only individual generators have access to. Normally unit status information is protected (cannot be made public) for 60 days. This provision can and should be waived by the Texas Public Utilities Commission in this situation to allow a full and public accounting of generator actions. The Electric Reliability Council of Texas (ERCOT) would typically issue a request for information to all generators to gather the reasons for specific outages, and some amount of time (7-10 days?) is needed to allow for the request, submittals and summary, but this process should be started and completed as quickly as possible so that legislative and regulatory deliberations are based on a solid basis of fact.
How did ERCOT’s forecasts deviate from actual events?
For example, what was the ERCOT assuming for forecasted temperatures? What was the forecast two weeks before, one week before and the day before the event? How did actual temperatures compare to these forecasts? How did temperatures last week compare to those that occurred in 2011 or 1989? When did the ERCOT realize forecasted loads exceeded the extreme weather conditions included in the Seasonal Assessment of Resource Adequacy (SARA)? When realized, to whom was that information communicated?
Did all distribution utilities fully and timely implement their load shed responsibilities?
Why were some utilities, such as Austin Energy, unable to institute rolling blackouts? What changes would need to be made to allow them to rotate outages in the future, and what would that cost? Does the ERCOT know the interconnection locations powering natural gas production or transmitting facilities? Do the Transmission and Distribution (T&D) utilities? Was any effort made to avoid curtailments of electricity to natural gas production or distribution facilities?
To what extent should weatherization changes go beyond the generators themselves?
For example, what winterization requirements exist to ensure production and deliverability of natural gas in the cold? What was the status of local natural gas storage facilities last week? Why are compressor stations powered with electricity rather than natural gas?
