Reliability and Resilience; Distinct Concepts with Unified Objectives - System Operation Perspective

Modern power systems are evolving rapidly to meet the demands of a changing energy landscape. They incorporate advanced technologies like smart grids, renewable energy sources, and energy storage solutions to enhance reliability and resilience. System operators play a crucial role in this context. System operators are responsible for several key tasks to ensure the stability and reliability of power systems. These tasks include monitoring and balancing supply and demand, coordinating transmission and distribution, integrating renewable energy sources, maintaining system reliability, and managing new technologies. By effectively performing these tasks, system operators help create a more reliable and resilient power system that can withstand and quickly recover from disruptions. 

𝗥𝗲𝗹𝗶𝗮𝗯𝗶𝗹𝗶𝘁𝘆; 𝗪𝗵𝗮𝘁 𝗶𝘀 𝗶𝘁 ?
The reliability of a power system is the probability of satisfactory operation over a long run.

𝗪𝗵𝘆 𝗶𝘀 𝗶𝘁 𝗶𝗺𝗽𝗼𝗿𝘁𝗮𝗻𝘁 ?
It ensures a continuous electricity supply to customers over a long period, which increases productivity and reduces disruption.

𝗥𝗲𝘀𝗶𝗹𝗶𝗲𝗻𝗰𝘆; 𝗪𝗵𝗮𝘁 𝗶𝘀 𝗶𝘁 ?
A power grid is resilient if it can withstand, respond to, and recover quickly from major disruptions that could potentially lead to a widespread electricity outage.

𝗪𝗵𝘆 𝗶𝘀 𝗶𝘁 𝗶𝗺𝗽𝗼𝗿𝘁𝗮𝗻𝘁 ?
It is essential because a resilient power grid prevents outages from affecting critical facilities such as hospitals, water treatment plants, and fire stations. These survival facilities need electricity 24/7, rain or shine.

As the operators of electrical grids, it is our job to keep the power flowing to millions of people across multiple cities and regions. Our system's reliability today and into the future is a testament to our commitment. But what do reliability and resilience really mean, and how do they differ? Today, we delve into these concepts with insights from our comprehensive Fuel Security Analysis, which aims to define resilience and its connection to reliability.

Reliability: The Cornerstone of Electrical Grid Operations

Reliability has been at the core of our mission since the early 20th century. It involves designing, operating, and maintaining the electricity supply to ensure an adequate, safe, and stable flow. In everyday terms, reliability means that when you get home, the lights come on, your refrigerator functions, and businesses operate continuously.

Traditional threats to reliability include the loss of generation, transmission failures, or demand disruptions. Examples include a generator breakdown, a substation trip, or a power outage due to a fallen tree. Equipment failures and extreme weather events are common threats. We are accountable to many federal and industry standards that ensure we maintain reliable operations. Our recent fuel security study underscores that our grid will continue to perform reliably under various stressed conditions.

Resilience: Preparing for the Unknown

Resilience is closely linked to reliability. You cannot be resilient without first being reliable. Resilience involves additional concepts: preparing for, operating through, and recovering from significant disruptions, regardless of the cause. It is about withstanding extreme or prolonged events. While some risks are considered in traditional reliability planning, evolving threats can outpace existing standards and regulatory requirements.

Determining how best to invest in resilience is crucial for our operations and stakeholders. Balancing costs with the likelihood of an event and the societal impact of extended electricity loss is vital. Striking the right balance requires ongoing discussion with stakeholders, regulators, legislators, consumer advocates, and the broader electricity industry.

Shared Objectives of Reliability and Resilience

Core functions of planning and operating the grid are rooted in shared objectives of reliability and resilience:

1. Keep the Power On: We work around the clock to balance supply and demand, ensuring continuous electricity flow. We plan and coordinate the dispatch of power plants and the operation of high-voltage equipment that transports electricity over long distances.

2. Minimize the Risk of Outages: We plan for a robust system that provides reliable and efficient electricity flow, minimizing interruptions.

3. Withstand Disruptions and Minimize Impacts: We monitor and adjust the power grid to withstand disruptions, reducing the impact of outages on customers.

4. Quickly Restore the System: We must be prepared to quickly and efficiently restore the electric system after an outage.

5. Incentivize Reliability: Competitive markets offer incentives that help maintain a reliable system and enhance resilience.

   

Grid operators can anticipate and prepare for certain threats, but not all can be foreseen, especially in a highly interconnected world with emerging threats. Therefore, the grid must be both reliable and resilient. Our fuel security analysis examines one aspect of resilience: the fuel supply that powers the generators. As we continue to study resilience and incorporate its attributes into operations, planning, and markets, we remain committed to ensuring cost-effective solutions for the customers in the regions we serve. By understanding and investing in both reliability and resilience, we ensure that the future of power remains bright and secure for all.