Daniel served as Assistant Secretary for Energy Efficiency and Renewable Energy — leading that office for all four years of the first Trump administration. The office has since been renamed the Office of Critical Minerals and Energy Innovation (CMEI), and it now sits at the center of the administration's energy agenda. In that role, Mr. Simmons held direct oversight responsibility for nearly $9 billion in federal funding and more than 800 staff, including oversight of the National Renewable Energy Laboratory.

That experience produced a vantage point available nowhere else. Mr. Simmons participated in the full lifecycle of DOE investment programs from the inside: the genesis of policy priorities within the administration, working with Congress on authorization and appropriations, the development and issuance of funding opportunities, the merit review and selection of awards, and post-award management and execution. He knows the individuals across DOE, the interagency process, and the White House policy apparatus who shape these programs — not from the outside, but as a peer and former colleague.

Before his Senate-confirmed appointment, Daniel was Vice President for Policy at the Institute for Energy Research. He has held senior policy roles at the American Legislative Exchange Council and the Mercatus Center at George Mason University. He is an attorney by training, nominated by President Donald J. Trump and confirmed by the United States Senate by unanimous consent.

Selected appointments

• 2018–2021 Assistant Secretary, Office of Energy Efficiency and Renewable Energy, U.S. DOE
• 2014–2017 Vice President for Policy, Institute for Energy Research
• 2010–2014 Director, Natural Resources Task Force, ALEC
• 2006–2010 Senior Research Fellow, Mercatus Center, George Mason University