Timothy A. Gessert, Ph.D.


From 1983-2015, Timothy Gessert worked for the National Center for Photovoltaics (NCPV) located at the National Renewable Energy Laboratory (NREL) in Golden, Colorado. During this time, he held all research-staff positions – from Research Technician to Principal Scientist. One of his more recent positions was Group Manager of the Polycrystalline Thin-Film Photovoltaic Devices Group. In this position he provided technical leadership and administrative support for more than 25 Junior and Senior Scientists, Technicians, and Graduate Students. From 2015-2017, Dr. Gessert also worked with EPIR Technologies in Bolingbrook, IL, as Senior Scientist in charge of Photovoltaic Research.

Dr. Gessert has served as technical advisor and graduate-review committee member for over 15 Ph.D. and M.Sc. students, and has also directly mentored more than 30 undergraduate students through programs such as the U.S. Department of Energy (DOE) Science Undergraduate Laboratory Internship (SULI) Program. He has also taught more than 1,000 students in short courses offered through various technical societies (e.g., AVS, MRS, IEEE) related to vacuum technology, transparent conducting oxides, and thin-film photovoltaic solar cells. He is presently or previously an adjunct faculty member at the Colorado School of Mines, Colorado State University, Vanderbilt University, and University of Illinois at Chicago. Dr. Gessert received numerous awards while at NREL for various technical and/or facility-design achievements. He is a Fellow of the American Vacuum Society (AVS), presently serves as Chair of the AVS Educational Committee, and is an Associate Editor for the scientific journal Thin Solid Films.

Technical Areas of Interest

Dr. Gessert has authored or co-authored over 230 Journal or Conference publications, authored or co-authored 6 book chapters, has more than 10 issued U.S. Patents, and has another >10 U.S. Patents published or pending. Tim has served on Conference and Program Committees for numerous national and international conferences. Most of his recent scientific work has involved development of novel electrical contacts for use in photovoltaic and other electronic devices, with an emphasis on enhanced functionality, environmentally stability, and/or commercial production advantages. His most-recent activities have been directed at understanding how choices in vacuum-processes consideration and/or overall device design affects the ultimate performance, stability, and other operational aspects of polycrystalline and crystalline photovoltaic devices. Many of the technical foundations initially reported in Tim’s publications are now incorporated into current-generation commercial photovoltaic solar cell products.

Education and More

Gessert received degrees in Physics and Mathematics from University of Wisconsin-River Falls (B.Sc., 1984), in Physics from Colorado School of Mines (M.Sc. 1984), and in Applied Physics from University of Wales – College of Cardiff (Ph.D., 1996). His Ph.D. work involved establishing the foundations for vacuum-processed ZnTe:Cu contacts that are now used in large-scale, CdTe-based, solar photovoltaic module production. The offices of Gessert Consulting are located at 9,000-feet elevation in the Colorado Rocky Mountains, near the small mountain town of Conifer. Tim maintains active investigations regarding development of next-generation, high-performance, lightweight/inexpensive photovoltaics, and how these devices could transform management of critical natural resources (e.g., improved remote sensing for precision agriculture, forestry, and water/wetlands).