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Ameren Illinois Announces Senior Leadership Changes

COLLINSVILLE, Ill. (MARCH 2, 2023) – Today, Ameren Illinois announced key senior leadership changes to support the company's strategic priorities and the retirement of two vice presidents, according to Lenny Singh, Chairman and President of Ameren Illinois. 

Kristol Simms has been promoted to the newly created position of Vice President of Clean Energy Transition, Economic, Community and Business Development for Ameren Illinois. In this newly created position, the functions responsible for energy efficiency, beneficial electrification, and economic development, and are being re-organized under Simms to optimize the company's grid transformation efforts to support the clean energy transition in Illinois.

As Senior Director of Energy Efficiency and Regulatory Policy Implementation, Simms led the implementation of market-leading energy efficiency programs, managing a portfolio of services which have reduced customer energy usage and met aggressive state-mandated energy savings targets.  

Simms began her career in the Ameren legal department in 2014 before being promoted to lead energy efficiency in 2018. She received her undergraduate degree from Lincoln University in Jefferson City, Mo., and holds a juris doctorate degree from the University of Missouri School of Law. Simms' appointment was effective March 1.

Matthew Tomc will be promoted to Vice President of Regulatory Policy and Energy Supply. Tomc will lead power procurement, natural gas procurement, regulatory affairs, and regulatory policy & rates for Ameren Illinois. His appointment is effective April 1.

As Director and Assistant General Counsel, Tomc has drafted legislation and litigated many of the regulatory reforms that have enabled Ameren Illinois to invest in its rate-regulated business and earn solid returns. 

Tomc holds a juris doctorate degree from the University of Kansas School of Law, and a bachelor's degree in economics from Emporia State University. 

Jim Blessing, Vice President of Regulatory Policy and Energy Supply, will retire on July 5. Blessing has held numerous leadership positions in his 29-year career with Ameren before serving as Vice President, Regulatory and Energy Supply. Over the next few months, Blessing will work with Tomc to transition leadership responsibilities.

Blessing holds a bachelor’s degree in electrical engineering from the University of Missouri-Rolla, and an MBA from Saint Louis University.  

Michael Mueller, Vice President of Economic Development, will retire April 10. In 38 years with Ameren, Mueller has held a variety of leadership positions in energy supply, energy management, and renewable development, including eleven years as President of Ameren Energy Fuels & Services Company. He joined Ameren Illinois in 2015 as Vice President, Economic Development.

Mueller holds a bachelor's degree in Mechanical Engineering from the University of Missouri, Rolla, and an MBA from Southern Illinois University Edwardsville.

"We're at the intersection of changing policies, technology, and customer expectations as we navigate the transition to a cleaner, more resilient energy grid," Singh said. "These leadership appointments will enable us to meet these complex challenges and continue to deliver strong results for our customers, communities, and shareholders."

About Ameren Illinois
Ameren Illinois delivers energy to 1.2 million electric and more than 800,000 natural gas customers throughout central and southern Illinois. Our service territory covers more than 1,200 communities and 43,700 square miles. Our mission is to power the quality of life. For more information, visit AmerenIllinois.com. Follow us on Twitter @AmerenIllinois and Facebook.