Timothy J Theiss

Timothy J Theiss

Interim Division Director, Buildings and Transportation Science Directorate

Mr. Theiss has been on the staff at ORNL since 1987, as a research development staff member, a group leader and a program manager.  He has over 20 years of experience in program development and program management at ORNL in various technical areas, primarily related to bioenergy and biofuels, distributed generation, power systems, and transportation.  Since 2011, Tim has been serving as the ORNL Laboratory Relationship Manager or Program Manager for the DOE Energy Efficiency and Renewable Energy’s Bioenergy Technologies Program.  The ORNL applied bioenergy program includes research on feedstock supply and logistics, biomass conversion technologies and the strategic analysis and sustainability of bioenergy.  Tim’s specific areas of interest include additive manufacturing (aka, 3D printing) with bio-derived materials, low carbon fuels for maritime applications bioenergy for carbon capture and sequestration.  In 2017, Tim was named the Group Leader for the Renewable Energy Systems group in the Environmental Sciences Division and was recently named the Interim Section Head for the Biodiversity and Sustainable Systems Section in ESD.  He has a BS degree in Engineering Science and Mechanics from Tennessee Tech and a Master’s degree in Engineering Mechanics from Virginia Polytechnic Institute (Virginia Tech).


• Federal Laboratory Consortium Award for Excellence in Technology Transfer for Low-Cost Cookstove Alloys as a contributing team member (2012).
• R&D-100 Award for High Performance Advanced Membranes as a contributing team member (2014).
• Letter of commendation from the US DOE for leadership and contributions to the 2016 Billion-ton Report.
• Member of The University of Tennessee Institute of Agriculture Advisory Council, Eastern Division.

“System for determining biofuel concentration” as a team member (2016)

Invited speaker for ENERGY Talks, DOE-wide seminar on “Recent Advances in Additive Manufacturing (3D Printing)”, Nov. 9, 2017.