Ryan Riedel, a former network engineer at SpaceX, has stepped down as chief information officer of the Department of Energy.
Dawn Zimmer, former principal deputy CIO, will serve as acting CIO, Nextgov/FCW reported Friday.
Riedel was named DOE CIO in early February and charged with overseeing a workforce of 15,000 professionals tasked with the agency’s technology policy and cybersecurity. He also supervised national labs, power marketing administrations and the National Nuclear Security Administration.
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Ryan Riedel’s Career
Prior to his DOE appointment, Riedel worked at Elon Musk-led Space Exploration Technologies, or SpaceX. He was the lead network security engineer at the Brownsville, Texas-based company from 2022. Before that, he served as a network security engineer.
The IT professional was also part of the U.S. Army Cyber Command as a network manager from 2019 to 2020. He also served for over seven years at Corpus Christi Army Depot, where he held vital positions such as network engineer, IT project manager and IT service desk lead.
Riedel also spent time with the Navy as a network administrator and communications security custodian. He served in various leadership roles during his seven-year career in the Navy.
Riedel has yet to announce a reason for his departure from the DOE.
Dawn Zimmer’s Career at a Glance
Zimmer is a 25-year veteran of the industry with extensive knowledge of IT, service delivery, business partnerships, relationship management and strategic planning and execution. She was previously appointed acting CIO after the resignation of Ann Durkin. Zimmer joined DOE in November 2024 as principal deputy CIO.
The executive currently serves as executive director of information technology experience and engagement at Virginia Tech. She also previously served at the Federal Aviation Administration and the Department of Justice.
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