#10WeeksOfSummer: Managing a Power Grid

Every single day, the California Independent System Operator (ISO) works hard to manage the high-voltage transmission system that provides power to 30 million customers. In fact, the ISO grid is one of the largest in the world, encompassing three-quarters of California and a small portion of Nevada, helping to deliver over 260 million megawatt-hours of electricity each year.

As the operator of the state-wide power grid, the ISO is the ‘balancing authority’ that assesses the status of the transmission system at all times. Every five minutes, the ISO forecasts, or predicts, how much energy Californians will be using based on weather forecasts, the time of day and events that demand electricity throughout the state of California.

How does SDG&E fit in?

On any given day, we, at SDG&E, are in close coordination with the ISO to ensure that enough energy is flowing through the electric grid to safely and reliably meet customer demand no matter if we are experiencing a rain storm, heat wave or even a solar eclipse. It takes a lot of planning, preparing and energy forecasting to make sure there is the right balance between supply and demand. With organizations like the ISO taking the lead in coordinating the operation of the power grid, customers can rest assured that there is a system of checks and balances to ensure electricity is available when they need it, 24 hours a day, 365 days a year.

Things that happens on the state-wide grid don't always have direct impacts to SDG&E’s system. However, since the grid is interconnected, a potential shortage in the north can ultimately affect us in the south. This concern is exactly why we have a direct line to the ISO should an event arise. 

Running a power grid takes planning

Just one example of the type of planning grid operators and power companies must make is in preparation for the summer months. Every year, the ISO and SDG&E take added measures to secure enough energy to serve the needs of our customers and the region. This year was no different. When temperatures rise, so does air conditioning use, which is why the ISO and SDG&E keep a close eye on energy consumption on an hour-by-hour basis. Any time there is a possibility that energy demand will exceed supply, there is a chance that a ‘Flex Alert’ or ‘Call for Conservation’ might be issued in order to stabilize the imbalance on the grid. That is when we call on our customers to do their part to save energy at their home or business.

What can you do?

Managing the power grid takes team work. While we work closely with the ISO, we  encourage you to manage your use at home to help conserve energy and save money. There are tools and resources we provide that make it easy to set energy goals. To receive energy alerts, use  our Energy Management Tool on My Account. This helpful tool will send you emails or text alerts when your energy use or spending goal reaches a certain limit.

To learn about additional ways to save energy and money, visit sdge.com/summer.

Editor’s note: this article is part of SDG&E’s #10WeeksOfSummer campaign, where customers can learn more about how we power San Diego and southern Orange coun and get tips & tools to help you save money and energy.