A new report from University of Texas at Austin energy experts lays much of the blame for power outages during the state’s deadly February freeze on the failure of natural gas producers to fully weatherize their facilities.”
The natural gas system could not meet demand,” the authors of the 101-page study wrote. “The production losses stemmed principally from freeze-offs, icy roads and electric outages to the equipment used in the natural gas industry.”
UT issued the study Tuesday, the same day the state’s health department revised its official death toll from the disaster, raising it to 210 from 151. However, at least one data-driven report suggests the actual number may exceed 700.
For the study, UT researchers looked at the performance of 27 natural gas facilities during the freeze and found that as temperatures dropped, the operators’ pipelines and equipment ceased to function, resulting in an 85% falloff when power companies needed the fuel.
Indeed, 18 of the natural gas facilities it studied had “zero output” on February 17, the peak of the storm.
In addition to their human cost, the failures resulted in massive charges for the state’s power generators, according to the report. CPS Energy, for example, tallied losses on natural gas fuel purchases of as much as $850 million, and losses on purchased power costs of as much as $250 million.
The 101 page report is here. Neither of us is likely to read through the whole thing, but the Findings section of the Executive Summary give you the main points:
The failure of the electricity and natural gas systems serving Texas before and during Winter Storm Uri in February 2021 had no single cause. While the 2021 storm did not set records for the lowest recorded temperatures in many parts of the state, it caused generation outages and a loss of electricity service to Texas customers several times more severe than winter events leading to electric service disruptions in December 1989 and February 2011. The 2021 event exceeded prior events with respect to both the number and capacity of generation unit outages, the maximum load shed (power demand reduction) and number of customers affected, the lowest experienced grid frequency (indicating a high level of grid instability), the amount of natural gas generation experiencing fuel shortages, and the duration of electric grid operations under emergency conditions associated with load shed and blackout for customers. The financial ramifications of the 2021 event are in the billions of dollars, likely orders of magnitude larger than the financial impacts of the 1989 and 2011 blackouts.
Factors contributing to the electricity blackouts of February 15-18, 2021, include the following:
- All types of generation technologies failed. All types of power plants were impacted by the winter storm. Certain power plants within each category of technologies (natural gas-fired power plants, coal power plants, nuclear reactors, wind generation, and solar generation facilities) failed to operate at their expected electricity generation output levels.
- Demand forecasts for severe winter storms were too low. ERCOT’s most extreme winter scenario underestimated demand relative to what actually happened by about 9,600 MW, about 14%.
- Weather forecasts failed to appreciate the severity of the storm. Weather models were unable to accurately forecast the timing (within one to two days) and severity of extreme cold weather, including that from a polar vortex.
- Planned generator outages were high, but not much higher than assumed in planning scenarios. Total planned outage capacity was about 4,930 MW, or about 900 MW higher than in ERCOT’s “Forecasted Season Peak Load” scenario.
- Grid conditions deteriorated rapidly early in February 15 leading to blackouts. So much power plant capacity was lost relative to the record electricity demand that ERCOT was forced to shed load to avoid a catastrophic failure. From noon on February 14 to noon on February 15, the amount of offline wind capacity increased from 14,600 MW to 18,300 MW (+3,700 MW).2 Offline natural gas capacity increased from 12,000 MW to 25,000 MW (+13,000 MW). Offline coal capacity increased from 1,500 MW to 4,500 MW (+3,000 MW). Offline nuclear capacity increased from 0 MW to 1,300 MW, and offline solar capacity increased from 500 MW to 1100 MW (+600 MW), for a total loss of 24,600 MW in a single 24-hour period.
- Power plants listed a wide variety of reasons for going offline throughout the event. 3 Reasons for power plant failures include “weather-related” issues (30,000 MW, ~167 units), “equipment issues” (5,600 MW, 146 units), “fuel limitations” (6,700 MW, 131 units), “transmission and substation outages” (1,900 MW, 18 units), and “frequency issues” (1,800 MW, 8 units). 4
- Some power generators were inadequately weatherized; they reported a level of winter preparedness that turned out to be inadequate to the actual conditions experienced. The outage, or derating, of several power plants occurred at temperatures above their stated minimum temperature ratings.
- Failures within the natural gas system exacerbated electricity problems. Natural gas production, storage, and distribution facilities failed to provide the full amount of fuel demanded by natural gas power plants. Failures included direct freezing of natural gas equipment and failing to inform their electric utilities of critical electrically-driven components. Dry gas production dropped 85% from early February to February 16, with up to 2/3 of processing plants in the Permian Basin experiencing an outage.5
- Failures within the natural gas system began prior to electrical outages. Days before ERCOT called for blackouts, natural gas was already being curtailed to some natural gas consumers, including power plants.
- Some critical natural gas infrastructure was enrolled in ERCOT’s emergency response program. Data from market participants indicates that 67 locations (meters) were in both the generator fuel supply chain and enrolled in ERCOT’s voluntary Emergency Response Service program (ERS), which would have cut power to them when those programs were called upon on February 15. At least five locations that later identified themselves to the electric utility as critical natural gas infrastructure were enrolled in the ERS program.
- Natural gas in storage was limited. Underground natural gas storage facilities were operating at maximum withdrawal rates and reached unprecedently-low levels of working gas, indicating that the storage system was pushed to its maximum capability.
The ERCOT system operator managed to avoid a catastrophic failure of the electric grid despite the loss of almost half of its generation capacity, including some black start units that would have been needed to jump-start the grid had it gone into a complete collapse.
Just as a reminder, the grid was not on the first special session agenda, and as of today isn’t on the second session’s agenda. I have heard it suggested that Abbott could add grid items to the agenda, or put them on but near the bottom of the agenda for this special session, to make it harder for the Dems to be away. The main problem with that analysis is that Abbott has been busy telling everyone in sight that the grid has been totally fixed. What’s to put on the agenda if that’s really the case? His problem for now, all of ours the next time the words “rolling blackouts” get mentioned.