Peak Events

By taking energy management measures during system peaks each summer, we can all help reduce our transmission costs for the following year.

What are peaks?

Each year, transmission costs are based on a value called Four Coincidental Peaks, or 4CP. Our 4CP is the measure of PEC’s total energy demand when our statewide transmission system experiences the most overall demand — the four “peaks” — each summer. The lower PEC’s demand is during these peaks, the lower our transmission costs will be the following year.

The four peak events occur once each month in June, July, August, and September, usually between the hours of 3 and 7 p.m. They’re triggered when system demand is highest: usually on the hottest days of the month during the post-work/dinner hours when we’re all arriving home, turning on the air conditioning, starting dinner, and running large appliances like dishwashers.

We can’t avoid peaks, but we can reduce the amount of energy we use during peak times. Every bit counts toward a lower bill next year.

How will I know a peak event is happening?

PEC doesn’t receive advance notice of the four peak events, but they often fall between 3 and 7 p.m. on the hottest days of the summer months. We will notify members throughout the summer of potential peak days so we can be prepared.

Remember that 4CP is a statewide measurement, and sometimes weather in other areas, like Houston or Dallas, can have a significant impact on peak demand across the state. It’s smart to keep an eye on the weather, plan ahead, and be in the habit of reducing your overall use and shifting high-energy use tasks away from these hours.