The Texas Blackout: Key Factors that Nearly Caused a Grid Failure | Aspenia Online

Jun 10, 2021 | Article

The Texas Blackout: Key Factors that Nearly Caused a Grid Failure

Co-authored by EnerNex and CESI

Aspenia Online

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  By: Ron Chebra, VP of Grid Modernization
  rchebra@enernex.com
  865-770-4874

 

The electric grid has been classified as one of the largest and most complex machines in the world and ranks first as the “Greatest Engineering Achievements of the 20 Century” by the National Academy of Engineering. Delicately balancing production and consumption of energy, a product that operates at the speed of light with a goal of 99.9% availability or one hour of outage per year, is no trivial effort. However, the events in Texas in mid-February clearly demonstrate how fragile the management of the grid can be. Studies are underway that will uncover more details about the root causes and mitigating circumstances, informing the development of subsequent remediation and calls to action. However, it is evident from early analysis that there were a series of factors leading up to a compounding set of conditions that resulted in loss of power for millions of customers. The fundamental cause can be attributed to extreme cold weather that negatively impacted energy production and fuel supply. The same freezing temperatures created a high demand, which exceeded the expected winter peak by 30% and reached summer levels. Temperatures dropped below -8°C during the storm, with wind and humidity that led to perceived temperatures of -17°C on February 15th. Due to the imbalance of supply, the Electric Reliability Council of Texas (ERCOT – the grid operator), used emergency procedures that included rolling brown-out and emergency load reduction measures. At the peak of the shortage, about 10 GW of customer load had to beshed when the difference between total power supply and demand dropped below 1 GW. Key underlying issues regarding shortages of energy due to inadequate supply include a lack of proper winterization of many of the production assets, which caused them to operate at reduced capability or to go off-line entirely; limited reserve capacity that could dispatched; shortages of natural gas supply to fuel the primary generation sources; and constraints on what power could be imported into the islanded Texas grid that is unique in the US.

The amount of renewable capacity provided by wind power in 2020 for this market was approximately 25 GW, with natural gas dominating the market with approximately 50% fleet capacity. There was some degradation of wind power during the freeze when about 18 GW of wind power was offline at the peak loss compared to 28 GW from thermal sources; a nuclear reactor in Bay City was also shutdown resulting in a loss of 1.3 GW due to freezing feedwater.

On the demand side, Texas is generally in a moderate temperature zone; therefore, many residential dwellings are heated by resistive units directly or they have heat pumps that require electric supplemental heating when temperatures fall below their rated capability. According to the Energy Information Administration, approximately 60% of the homes in Texas use electricity as their primary heating source and winter demand over the years has been rising, reflecting the growth of both heat pumps and the population. The remaining heating customers use natural gas, which saw a peak demand during this period, which further contributed to the natural gas fuel shortage for power plants.

In addition, the commercial structure in the Electric Reliability Coordinator of Texas is an energy only market with little or no incentive to operate in the capacity market, thus further exacerbating the lack of standby resources.

Given the open market structure supply and demand pricing, many customers saw their energy bills soar as their typical supply costs rose from $20 to $30 per MWh to the cap of $9000 per MWh for more than 80 hours, resulting in the most expensive week ever in US power markets. The price spikes for many customers represented bills that were 20-30 times their normal monthly supply fee. This situation has driven a specific Public Utility Commission of Texas to conduct studies on Wholesale-indexed Compliance with Customer Protection Rules for Retail Electric Service and a review of ERCOT Scarcity Pricing Mechanism.

In the last decade, Europe has also been repeatedly hit by cold spells, notably in 2012. The first half of February 2012 was characterized by extremely low temperatures and demand reached a historical peak of 557 GW. In fact, in some countries sensitivity of load to temperature is significantly high. Despite prolonged and widespread extremely low temperatures that lasted for two consecutive weeks, no major disruptions in the power sector were recorded thanks to an efficient coordination between electric and gas operators (technically Transmission System Operators, TSOs). An efficient coordination between electric TSOs displaced the necessary actions to manage the stressed system: System operators made use of all available control reserves to supply electricity to customers, while maximizing import contributions. Additional measures were also used, including calling for decreases in demand through the media and other technical arrangements to ensure the continuity of supply. All that was possible thanks to strong interconnections between the European countries. A sufficiently high cross-border power transfer capacity turned out to be a key factor in stabilizing the power-demand balance in such a critical situation. To avoid adverse consequences when facing similar events in the US, a full integration of the pan-US power system must be pursued, as already envisaged by several studies that have not materialized in concrete interconnection projects between Eastern, Western and ERCOT power systems.

While the short-term and longer-term remedies are being hashed out at the legislative, regulatory and even judiciary levels, some of the immediate recommendations being instituted are: acting upon best practices for winterization of assets (many of which were outlined in a study done after a similar but lesser winter storm in 2011); improving standards for ensuring essential loads are served; more effective use of customer demand response and load shedding, including one recommendation to use the service disconnect capability that exists in most of the AMI meters in this market; greater emphasis on reliability measures under emergency conditions and; creating a more effective and integrated customer dialogue, especially as it relates to information and measures that are being taken and that can be taken to improve the reliability of the grid.

What are some of the early take-aways and lessons learned? Climate change is happening and severe weather events will be the result. The energy infrastructure must be hardened and made more resilient to these events, resorting also to adequate interconnections between power systems to ensure continuity of supply. Furthermore, renewable energy must be made more reliable through proper precautionary measures (e.g., wind turbines do operate in cold weather conditions) and increased use of battery energy storage should be considered to mitigate more resource uncertainty. In addition, there will likely be many cases in which self-contained microgrids will be implemented to improve the ability to meet high availability goals and reduce risks. Finally, improvements must be made on predictive models to provide better forecasts and anticipate possible remedies.

Smart Metering (SM) and Advanced Metering Infrastructure (AMI)

Smart Metering and AMI is a transformational process addressing multiple business and technical needs of the utility enterprise. This is more than just smart meters and communications networks; it includes all of the back end applications that can leverage the meter assets, such as outage notification, demand response, call center optimization, disputed billing process handling, pre-payment opportunities, and service connection management methods and procedures, to name a few.

Implementing SM and AMI faces the same business, engineering, and operational challenges as any other across-the-utility information technology endeavors – most notably risk associated with embracing proprietary technology, missing functionality and early obsolescence. Effective SM and AMI development, implementation, and operation relies on a marriage of electric power engineering with information technology expertise: a key component of EnerNex’s expertise and experience.

EnerNex provides an array of engineering and consulting services geared towards intelligent and effective implementation of SM and AMI. This covers all phases of project development, starting with capturing system requirements where our experts leverage a “Use Case” centric view of activities needed to be accomplished and their interaction with systems and other users. Subsequent project steps typically examine other critical areas, such as: modeling of business cases, building inter-department consensus, assembling and assessing system functional requirements and non-functional requirements, developing a system design, hardware and software specifications and standards, complete procurement services including RFI and RFQ process support, supplier rating system, response evaluation methodology, deployment management, and training of office and field personnel.

Demand Response (DR)

Demand response can be as simple as load interruption directed by the energy supplier in response to severe demand requirements, to complex customer defined load management in response to price signals. DR is one of the components of a “Non-Wires Alternative” that many utilities are effectively using to avoid expensive distribution fortification or upgrade.

 

Often the success and/or failure of demand response programs can be linked to program implementation challenges such as rate/tariff design rate structures communication (e.g. price signals) or ineffective incentives used by utilities to encourage customers to accept operational change. The issues of program design, rate structure and customer impact have a tremendous influence on the success or failure of load management initiatives. Demand response has traditionally been used as a tool of the energy industry to ensure system stability. However, the introduction of microelectronics, communications, home automation and the Internet of Things (IoT) has led to the development of cost effective solutions that have the capability to allow the consumer to take control of managing their energy load and ultimately, the price they pay for energy.

EnerNex has the experience and skills to turn your DR program into a successful operational asset and customer engagement process that can deliver value to all parties.

Energy Assurance Planning

Natural and man-made disasters cause an estimated $57B in average annual costs for all parties; large single events have resulted in losses of $100B or more. Events, such as the World Trade Center disaster, Hurricane Katrina, and most recently Hurricane Helene, have demonstrated an acute need to revisit, revise and implement an effective energy assurance plan. Energy assurance plans assess the functionality and interdependencies of buildings and infrastructure systems and the role they play in sustaining service and rapidly restoring critical services to a community following a hazard event.

 

EnerNex assists our clients in developing comprehensive energy assurance plans that mitigate and minimize the impact of energy disruptions. Our experts assess critical infrastructure risks and evaluate appropriate mitigation strategies and can help in developing an effective business continuity/disaster recovery (BC/DR) plan for utilities and your customers.

Microgrid Development

As the electric grid becomes more distributed and interactive, microgrids are playing an increasingly important role in our energy future. Decision makers at military bases, corporate and institutional campuses, residential communities and critical facilities across the world are exploring and implementing microgrids to meet economic, resiliency and environmental goals. Utility-grade microgrids are being deployed to meet transmission constraints, reliability requirements and safe-havens in the event of a significant storm event.

Microgrid_development Graphic steps to support grid modernization

Bringing together a portfolio of distributed energy resources into a controllable, islandable microgrid comes with its own set of challenges. The key to solving these challenges is in architecting a system to support information exchanges between components across well-defined points of interoperability (interfaces) in a technology independent manner. This interoperability ensures that the system is resilient to technology change. Modern systems engineering techniques must be employed to ensure that individual sub‐systems are clearly identified, their functions enumerated, their data requirements known, and the points of interoperability clearly specified, along with the commensurate monitoring, command and control that is needed to ensure grid stability. With such architecture, we can apply best of breed technology available today to support those information exchanges at interface boundaries but be free to upgrade / change the implementation technology later without causing a ripple effect throughout the system.

Enterprise Architecture

Enterprise Architecture focuses on aligning an organization’s business strategies with its anticipated, desired and planned technology enhancements. Enterprise Architecture provides a framework to cost-effectively transition from a current “as-is” technology to future enterprise-wide technological solutions. An effective Enterprise Architecture program aligns business investments with long-term business strategies while minimizing risk and providing superior technological solutions. EnerNex’s key asset is its highly skilled and experienced staff who are closely connected to both the smart grid and EA standards and practices. We provide clients with the insight necessary to operate a fully functioning smart grid, which is flexible, scalable, and vendor independent.

Grid Modernization Roadmap

Utility companies across the globe are continually modernizing their grid. Each company often has different rationales, objectives and priorities. Frequently, smart grid plans are developed for individual, incremental initiatives, rather than as a part of a whole, intelligent and interoperable infrastructure. Planning may be developed around technology choices rather than business and technical requirements. The result of incremental and flawed planning leads to increased cost and risk, lost opportunities, disconnected expectations and dead ends.

 

EnerNex’s approach to grid modernization roadmap development follows a proven, industry-standard approach to grid modernization planning by collaboratively working with the utility to develop a set of prioritized and time-phased grid modernization initiatives unique to its business strategy and objectives. The roadmap developed is holistic, requirements-based, business value driven and actionable. It often builds on and leverages existing applications and infrastructure, and incorporates industry standards to ensure interoperability, flexibility and reduced cost and risk.

Utility Communications

Utility communication and control systems are increasingly interconnected to each other and to public networks and as a result, they are becoming increasingly more susceptible to disruptions and cyber attacks. EnerNex has experience with the various issues relating to development, implementation and optimization including feasibility analysis, design, software development and customization, project management and acceptance. Our expertise extends from being involved in the development of the fundamental standards that support utility communication and automation, through deployment and securing of those resources. EnerNex personnel were heavily involved in development of such standards and protocols as IEC 61850, IEC 60870-5 and DNp3. Our staff played a key role in the EPRI Utility Communication Architecture (UCA) project and the IntelliGrid Architecture effort.

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