As Winter Unfolds: Has ERCOT Learned from 2021's Lessons?

Texas winters have rarely been mild in their surprises, but few were as unforgiving as Winter Storm Uri in 2021. The Electric Reliability Council of Texas (ERCOT), which oversees 90% of the state’s electric load, faced a catastrophic failure.

Millions lost power for days, and tragically, lives were lost. Now, in 2025, ERCOT stands at the crossroads of accountability and preparation. Has the grid operator taken the lessons of 2021 to heart, or is Texas bracing for déjà vu?
‍

A Look at 2025’s Challenges

The 2025 winter is shaping up to test ERCOT’s resilience yet again. Freezing temperatures are expected across the northern and western parts of ERCOT’s jurisdiction, with snowfall even reaching Dallas.

ERCOT forecasts system-wide demand to peak near 68,000 MW a few days ago, while renewable energy contributions are predicted to drop below 6,000 MW during the evening hours​.

This sets up a challenging scenario: high demand, reduced renewable generation, and potential turbine icing in key wind farm areas​.
‍

Wind turbines in northern and western Texas are particularly vulnerable. The data indicates turbine icing risks for this region, compounded by suboptimal renewable energy outputs​. While freezing rain and icing events are infrequent in Texas, their impact on wind energy generation can be disproportionate.

Historical data reveals that icing-related energy losses are typically minimal—0.64% of potential output over the past five years—but 2021 demonstrated how severe exceptions can wreak havoc​.
‍

Lessons Learned—or Not?

Since 2021, ERCOT has taken steps to weatherize its energy infrastructure, conducting over 3,000 inspections and enforcing stricter compliance measures. This includes cold-weather retrofits for power plants and enhanced winterization protocols for wind and solar resources. Some of the specific upgrades include:
‍

1. Control Algorithms and Heating Systems: Wind turbines have been fitted with cold-weather grease, heated nacelles, and advanced control algorithms to optimize operations during freezing conditions.

2. Prevention Over Reaction: For solar facilities, panels are stored in inclined positions to prevent snow accumulation, while wind farms leverage remote monitoring to anticipate icing events​.
‍

However, critical gaps remain. Cost-benefit analyses have deterred the implementation of more robust anti-icing technologies, such as blade heating via embedded thermal elements. Additionally, retrofitting older turbines remains economically and logistically infeasible, limiting improvements to the existing infrastructure​.

‍

Winter 2025 vs. 2021: How Different is it?

The stark difference between 2021 and 2025 lies in ERCOT’s operational tools and planning capabilities. During Winter Storm Uri, the grid operator underestimated extreme demand scenarios and overestimated generation capacity. Since then, ERCOT has significantly improved its forecasting abilities, integrating historical weather data and market behavior into real-time predictive models.

Arcus's Pwrstream, for instance, allows participants to juxtapose current generation forecasts against historical data, offering a clearer picture of constraints​.

ERCOT’s ability to monitor and predict turbine icing risks has also evolved. Unlike in 2021, operators now have granular insights into icing conditions, enabling preemptive shutdowns or operational adjustments to mitigate damage​. Still, the efficacy of these measures depends on execution under real-world conditions, which are often messier than models.

‍

The Icing Problem: Mitigation or Acceptance?

De-icing remains a contentious issue. Technologies such as embedded heating elements or chemical de-icing solutions, commonplace in colder climates, are deemed impractical for ERCOT due to their cost and environmental implications. Instead, ERCOT relies on strategic operational adjustments, including yaw and pitch control, to minimize icing exposure. While these measures are cost-effective, they are far from foolproof​.

The economic argument against widespread deployment of blade heating systems highlights a broader tension in ERCOT’s strategy: balancing costs with resilience. Infrequent icing events make expensive retrofits a tough sell, yet the outsized impact of even one storm like Uri challenges this logic.

Renewables and Reliability: The Balance

As Texas grows its renewable energy sources, it still relies on weather-sensitive resources like wind and solar. This reliance has both benefits and drawbacks. Although renewable integration boosts grid sustainability, its fluctuation during peak winter demand stresses the necessity for backup capacity.

ERCOT’s reserve margin has gotten better since 2021. This improvement comes from investments in natural gas and battery storage. However, critics say it still does not guarantee reliability during extreme conditions.

ERCOT anticipates that renewable generation will dip significantly during peak evening hours, leaving natural gas plants to shoulder the bulk of the load. This dependency on thermal generation raises questions about fuel supply integrity, another Achilles’ heel exposed during Uri​.

So, Can ERCOT Handle This Winter?

The short answer: probably, but with caveats.

ERCOT’s post-2021 reforms have undoubtedly strengthened the grid’s ability to weather typical winter storms. Enhanced weatherization, improved forecasting, and better operational coordination offer significant safeguards against widespread blackouts. However, the system’s resilience against outlier events—such as prolonged freezing temperatures or cascading failures—remains unproven.

As the winter storm unfolds, the true test will lie in ERCOT’s execution. Will operational adjustments, turbine monitoring, and natural gas ramp-ups perform as planned? Or will unforeseen complexities unravel months of preparation? Only time will tell.

A Path Forward

For ERCOT and its stakeholders, 2025 offers a chance to solidify progress and tackle lingering vulnerabilities. Key areas of focus should include:

1. Expanding Backup Capacity: Diversifying energy reserves with scalable battery storage and flexible demand response programs.
2. Investing in Resilient Infrastructure: Prioritizing cost-effective retrofits for high-risk assets, particularly in icing-prone regions.
3. Enhancing Transparency: Keeping the public and market participants informed about real-time conditions to foster trust and cooperation.

As Texas braces for another winter, one thing is clear: the stakes are high, and complacency is not an option. ERCOT has learned much since 2021, but whether those lessons translate into action remains the ultimate test. Let’s hope they pass.