Smart Energy Plan

May 06, 2026

New circuit breakers benefit 8,000 Ameren Missouri customers

Upgrades will reduce costs and support greater reliability at Lake of the Ozarks

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Circuit breakers play an important role in the reliability of your electric service. Inside your home, they protect your electrical system from overloading. And they play a similar role in the larger electric grid by protecting critical assets, such as substations, from power surges.

At Lake of the Ozarks, Ameren Missouri is upgrading two obsolete oil circuit breakers at its Osage substation to support reliability for customers. The Osage substation is located inside Ameren’s Lakeside Operating Center and is one of the first “stops” for energy leaving the generators at Bagnell Dam. The Osage substation supports approximately 8,000 customers in the area, mostly north and west of the dam. The project includes several customer benefits:

• Eliminates obsolete oil circuit breakers that are more than 55 years old.
• Reduces maintenance costs for obsolete equipment.
• Adds safer, more reliable vacuum circuit breaker technology.

“Oil circuit breakers are being phased out across the system in favor of more reliable air- and gas-based breakers,” says Matt Haffer, manager of substation construction for Ameren Missouri. “These upgraded circuit breakers are safer, better for the environment and, most importantly, support greater grid reliability for our customers.”

Ameren Missouri has upgraded more than 150 oil circuit breakers through the Smart Energy Plan, including earlier circuit breaker upgrades at the Osage substation. This project will upgrade the last two oil circuit breakers at this site. The upgrades are expected to be completed and in-service by fall 2026.

To learn about reliability upgrades in your area, visit Ameren.com/Reliability.

Old circuit breaker (left) versus new upgrade (right).