Texas’ grid operator said it would consider increasing coordination with other power regions, incorporate solar forecasts into its modeling and integrate more distributed resources and energy storage into the state’s minimally regulated system to improve reliability.
The proposals are among many included in a 60-point plan the Electric Reliability Council of Texas delivered July 13 to the state’s governor in response to an energy crisis that left millions of Texans without power for days during freezing temperatures earlier this year. Experts at the University of Texas at Austin in a new report said no single cause was behind the catastrophic grid disaster that resulted in significant loss of life and nearly $200 billion in property damages during the mid-February storm.
All types of generation technologies failed during the crisis, a committee of faculty and staff at the university said in an analysis detailing the timeline and events of Texas’ February 2021 blackouts. Both demand and weather forecasts for the period were overly optimistic, leading to a rapid deterioration in grid conditions beginning early Feb. 15 that culminated in a net loss of 24,600 MW on the ERCOT system in a single 24-hour period, the report says.
Power plants tripped offline due to weather and equipment issues; transmission and substation outages; and frequency issues, the report says. Some power plants crashed at temperatures above those in their stated minimum ratings, making their weatherization inadequate to their claims and far below what was necessary to deliver in the severe storm. Beyond wind turbine icing, outages between Feb. 14 and 15 were mainly the result of frozen water intakes, sensing lines and other general equipment freezing, the report says.
Failures within the natural gas system exacerbated problems with electricity generation at power plants, and also squeezed supply leading to price spikes of about 1000 percent during the storm as demand shot up for gas to fuel power plants and provide heat across several states. Natural gas equipment froze in many instances, and storage facilities were operating at maximum withdrawal rates as two thirds of processing plants in the Permian Basin experienced an outage, the report says. The high gas prices rippled out across the region and will likely affect electric and natural gas utility bills both within and outside of Texas for years (see CEM No. 1646  and CEM No. 1634 [15.1]).
ERCOT and the Public Utility Commission of Texas decided to maintain the wholesale market price for electricity at its $9,000 cap for 32 hours during the storm in an effort to reduce demand and encourage maximum participation from generating units (see CEM No. 1633 ). The high prices that week led to payment defaults by ERCOT market participants, which could translate to increased electricity bills in Texas for years to come, the report says.
The researchers listed in the report nearly a dozen factors that together created the catastrophic near-failure of the Texas grid and noted that at least eight black-start units—which would be needed to jump-start the grid in the event of a total collapse—experienced outages or derates related to either weather or equipment failure. If even one of the several problems had been avoided, they wrote in the 101-page report, “outages might still have occurred, but their duration and severity would likely have been lower.”
Gov. Greg Abbott, in a July 6 letter to the PUCT, asked the regulatory body to go beyond the changes mandated in legislation passed since the crisis. He directed the commission to “immediately” streamline incentives within ERCOT to foster “the development and maintenance of adequate and reliable sources of power like natural gas, coal, and nuclear power.” He characterized such resources as “the types of electric generators we need for reliability purposes” and asked the PUCT to instruct ERCOT to establish a maintenance schedule for non-renewable resources “to ensure that there is always an adequate supply of power on the grid” and to accelerate development of transmission projects to increase connectivity between dispatchable generation plants.
Abbott in the letter also directed the PUCT to “allocate reliability costs” to resources that cannot guarantee availability “such as wind or solar power.” He said not requiring such providers to shoulder the cost of their “failure” to provide sufficient capacity “creates an uneven playing field between non-renewable and renewable energy generators and creates uncertainty of available generation in ERCOT.”
ERCOT in a July 13 note accompanying the roadmap, told Abbott it is working with the PUCT to implement his directives. In the roadmap the grid operator said it had already completed a third of the 60 actions listed for improving reliability and was on track to complete the remainder within the timelines established by SB 2 and SB 3 passed by the Texas Legislature in the aftermath of the crisis and signed by the Governor in June (see CEM No. 1645 ). Abbott signed several other bills passed during this year’s legislative session that also relate to improving reliability and operations in the ERCOT system.
Actions in the roadmap range from procuring more resources to revising market rules, improving inspections and managing the state’s independent power grid “more aggressively.” The roadmap also emphasizes addressing transmission limitations and overhauling communications protocols to better serve all involved. Incorporating short term solar forecasts into modeling and eliminating barriers to distributed generation resources, energy storage and demand-response flexibility are other features of the plan.
ERCOT said it will conduct a study to understand future business drivers, including the integration of such resources on its system. Another planned study would gauge the impact of varying levels of wind and solar penetration, including the impact of energy storage and dispatchable resources and “revenue adequacy” for each of these levels, the roadmap says. Evaluating whether to require inverter-based resources such as wind and solar, methods for ensuring fuel security, improving system planning, verifying generator-reports through inspection and evaluating the adequacy and market conditions for ancillary services are other areas included in the roadmap as potential avenues for improved reliability.
ERCOT also included an action to work with the PUCT on “Black Start Plan improvements” it said would be designed to prevent the need for such a process while also streamlining protocols should the “one-in-a-million event” ever be necessary. ERCOT, in February, narrowly avoided such an event, which could have left the state without power for weeks.