The Photovoltaics (PV) team manages PV research and development projects that work to improve efficiency and reliability and lower manufacturing costs of solar panels, with an overall goal of driving down the cost of electricity from solar photovoltaic technologies. The team oversees innovative concepts and experimental designs across a range of materials that have the potential to make solar energy among the least expensive forms of electricity.

Dr. Lenny Tinker, Photovoltaics Program Manager

Lenny Tinker portrait

Dr. Lenny Tinker is the program manager for the Photovoltaics team. He has been at the U.S. Department of Energy Solar Energy Technologies Office (SETO) since September 2011 and started as an AAAS Science and Technology Policy Fellow on the Photovoltaics team working on Incubator Round 6. As a Federal employee, he now manages early-stage applied research and development programs at national labs, universities, and companies to develop advanced photovoltaic systems. Dr. Tinker is also the SETO Fellowship coordinator and is the SETO representative on the IEA PVPS Executive Committee.

Prior to his position in the Energy Department, Dr. Tinker was an Alexander von Humboldt Postdoctoral Fellow at the Westfälische Wilhelms-Universität in Münster, Germany, where he designed inorganic complexes to be used in organic light emitting diodes and to promote triplet-triplet upconversion processes. Dr. Tinker obtained a Ph.D. in chemistry from Princeton University and a B.S. from Beloit College. His Ph.D. research focused on visible light-induced water reduction using iridium(III) chromophores and colloidal catalysts to produce a portable fuel using sunlight.

Brion Bob

Brion Bob SETO Portrait

Dr. Brion Bob joined SETO in 2015 and now works as a technology manager within the Photovoltaics program. He currently supports program development toward advancing the cost-effectiveness of PV modules and systems as an increasingly significant part of the national energy portfolio. His professional interests include the creation of a national research base that accelerates manufacturing competitiveness while training the next generation of industrial researchers. Brion holds a B.A. in physics from Harvard University and a Ph.D. in materials science and engineering from the University of California, Los Angeles, where his graduate studies were focused on the areas of thin film solar cell fabrication and device physics, with additional work dedicated to investigating new contacts and junction architectures.

Patricia Clark

Patricia Clark SETO Portrait

Patty Clark is a technical project officer for the Solar Energy Technologies Office Photovoltaics (PV) team. Her job consists of budget planning, conducting financial compliance reviews, and invoicing and managing all financial reporting within the PV portfolio.

Patty has over 25 years of experience in the steel manufacturing industry with a background in energy efficiency, project management, and supervision of electrical engineer and electrical maintenance.

Patty received her BSAS in electrical engineering technology from Youngstown State University and her MBA from Lamar State University in Beaumont, Texas. She recently acquired her Professional Project Management Certification from Project Management Institute. Patty also has a six sigma black belt for professionals with an emphasis on lean manufacturing.

Noreen Gentry

Noreen Gentry SETO portrait

ORISE Science and Technology Policy Fellow

Dr. Noreen Gentry is an ORISE Science and Technology Policy Fellow for the U.S. Department of Energy Solar Energy Technologies Office (SETO). She joined SETO in November 2022 and works on the Photovoltaics team.

Prior to joining SETO Noreen earned her Ph.D. in inorganic chemistry from Yale University in 2022. Additionally, she has a Certificate of College Teaching Preparation and a Certificate for Public Communication from Yale. Her graduate work in Professor James Mayer’s lab focused on the proton-coupled electron transfer (PCET) chemistry of gold and titanium dioxide nanoparticle colloids. While at Yale, Noreen worked with an energy history professor to create a website and educational modules explaining the basic concepts of energy in an accessible way for non-scientists. She was also heavily involved in three groups in the Yale Chemistry department including the Joint Safety Team, the Professional Development Network, and the Diversity and Climate Committee.

She received her B.S. in chemistry from Iowa State University where she worked on the synthesis of nanoscale perovskites.

Tassos Golnas

Tassos is a Technology Manager for the Photovoltaics (PV) team, joining SETO in April 2016. His primary focus is solar power forecasting as a means for cost-effective integration of PV in the electric grid. As part of his responsibilities he oversees projects in the areas of solar resource assessment, PV system modeling, performance, monitoring, and reliability. He is also keenly interested in applications of blockchain technologies in transactive energy and retail electricity markets. Previously, he consulted for the World Bank Group. His solar career began at SunEdison where he worked as the Senior Manager of the Energy Analytics group, which developed algorithms for event detection, power forecasting, and inverter control, and generated analyses on power output variability and system reliability. He later became the Director of the Performance Analytics group, with responsibility for all performance reporting, analysis, and optimization. Prior to SunEdison, he worked for seven years in the semiconductor equipment and photonics industries as an R&D manager and engineer.

Tassos came to the U.S. in 1994 to earn a Ph.D. in Materials Science and Engineering at Stanford University. He lived in the San Francisco Bay Area until 2003, before moving to Chicago, and finally to Maryland in 2007. He holds a B.S. is in Physics from the Aristotle University in Thessaloniki. He has authored eleven papers on PV system analysis and holds four patents in sensors and process integration.

Susan Huang

Susan Huang Portrait

Dr. Susan Huang is a technical manager working on early stage research programs with the Photovoltaics team. Her interests are in improving the performance, understanding, and sustainability of next generation photovoltaic technologies. She joined the solar office in 2013 from IBM Research Yorktown Heights in New York. There she worked with manufacturing partners to develop and demonstrate novel silicon solar cell structures on production pilot lines. She received her Ph.D. in materials science and engineering from the University of Delaware, where she was part of the DARPA-funded Very High Efficiency Solar Cell program to develop a 50% efficient solar cell. Her research thesis was on III-V growth on silicon for tandem solar cell applications. She graduated from McGill University with a bachelor's of science degree in physics. During her undergraduate studies, she completed two internships at the National Renewable Energy lab on both renewable energy policies and solar cell hardware research.

Matt Klug

Matt Klug SETO Portrait

Company: Boston Government Services 

Dr. Matt Klug joined the U.S. Department of Energy Solar Energy Technologies Office (SETO) Photovoltaics team as a science and technology advisor in September 2023.  

Prior to joining SETO, Matt worked as a senior engineer at the R&D site of Oxford Photovoltaics to develop and commercialize perovskite-on-silicon tandem photovoltaics. While there, his efforts focused on materials and process development, sustainability topics, and serving as technical lead for several projects with external partners. While a post-doctoral researcher in Professor Henry Snaith’s research group at the University of Oxford, he studied how metal composition impacts the material, optoelectronic, and photovoltaic properties of perovskite absorbers. Matt holds a B.S. and M.Eng in mechanical engineering from Cornell University and a Ph.D. in mechanical engineering from the Massachusetts Institute of Technology (MIT), where he worked on several different solution-processed solar cell technologies as an energy fellow with the MIT Energy Initiative.

Inna Kozinsky

Inna Kozinsky headshot

Company: Allegheny Science and Technology

Dr. Inna Kozinsky is a science and technology advisor on the Photovoltaics team since October 2014. She is responsible for managing the PV program at the national labs as well as non-lab projects in thin-film photovoltaics, metrology, and modeling and characterization techniques. She is also responsible for the DOE PV Fleet Performance Data Initiative, which launched in 2019.

Before joining SETO, Inna was a senior research engineer at Robert Bosch Research and Technology Center in Palo Alto, CA, where she worked on thin-film silicon and CIGS PV research and development, optical and ab initio modeling of PV materials and devices, vibrational power harvesting, and MEMS sensors. She received her Ph.D. in physics from Caltech in 2007, where her thesis work focused on nonlinear dynamics in nano-electro-mechanical systems. Inna received a B.A. in physics and math and an M.A. in physics from Harvard University in 2000.

Marie Mapes

Marie Mapes Headshot

Dr. Marie Mapes is a photovoltaic technology manager for the U.S. Department of Energy (DOE)  Solar Energy Technologies Office (SETO). Her responsibilities focus on creating photovoltaic research and development programs that will advance the use of photovoltaic energy. Over her nearly 20 years in DOE, she has led over $100 million in programmatic activity on topics ranging from applied solar science; commercialization and manufacturing of photovoltaics; evaluation and assessment activities to improve the effectiveness of programs; workforce and development programs for solar scientists and engineers; and justice, equity, diversity, and inclusion of underrepresented minorities. She collaborated to bring DOE perspectives across private industry through a placement at NGEN Partners, a venture capital firm, and across federal agencies through work at the National Science Foundation. She entered the Energy Department in 2006 as a Presidential Management Fellow. Before coming to DOE, she earned a Ph.D. in physical chemistry from the University of Wisconsin—Madison and a bachelor’s degree in chemistry from Grinnell College. 


Larkin Sayre SETO Portrait

ORISE Science and Technology Policy Fellow

Dr. Larkin Sayre is an ORISE Science and Technology Policy Fellow for the U.S. Department of Energy Solar Energy Technologies Office (SETO). She joined SETO in January 2023 and works on the Photovoltaics team.

Prior to joining SETO, Larkin earned her Ph.D. in materials science from the University of Cambridge in 2022. She also holds an MPhil degree in energy technologies from the University of Cambridge and a B.S. in mechanical engineering from the Massachusetts Institute of Technology (MIT). Her graduate work in Professor Louise Hirst's group focused on developing ultra-thin single-junction GaAs solar cells with enhanced radiation tolerance for space power applications. While at Cambridge, Larkin rowed with the Cambridge University Women's Boat Club in the 2019 Oxford-Cambridge Boat Race and was president of the club in 2020. As president, she worked towards the successful merger between the men's and women's clubs for the first time in the almost 200-year history of the race. While at MIT, she focused on machining and manufacturing and was an apprentice in the Pappalardo Lab. She also worked with Violence Prevention & Response at MIT Medical as a student volunteer and captained the openweight women's varsity rowing team where she received All-Region D1 honors.

Timothy Siegler


Dr. Tim Siegler is a technology manager working on research and development projects. He joined the U.S. Department of Energy Solar Energy Technologies Office (SETO)  as an ORISE Science and Technology Policy Fellow in September 2021 and transitioned to a federal employee in February 2023. His primary interests are in emerging technologies for thin film photovoltaic modules, perovskite photovoltaics, and tandem photovoltaic technologies.  He is also interested in machine learning, materials development for solar technologies, reliability of solar plants in adverse or extreme weather events, and decarbonized supply chains, among other interests.

Prior to joining SETO, Tim was a post-doctoral researcher at the University of Washington focused on reliability of halide perovskite. He holds a B.S. in chemical engineering with a materials concentration from the University of Notre Dame and a Ph.D. in chemical engineering from the University of Texas at Austin. His graduate work focused on perovskite-CdTe tandem photovoltaic devices and the interactions of metal halides with ambient humidity.  

Nancy Truong

Company: ManTech International

Nancy Truong is the financial program analyst supporting the Photovoltaics team. Her job consists of budget planning, financial compliance review, and other various financial project management for the Photovoltaics portfolio. Nancy has 10+ years in accounting experience in the information technology, telecommunication, and hospitality industry.


Allan Ward SETO Portrait

Company: Boston Government Services

Dr. Allan Ward is a photovoltaic (PV) scientist and technology manager for the Solar Energy Technologies Office (SETO), working as a member of the Photovoltaics team since May 2020. He currently supports PV development projects focused on innovations in materials and designs for low cost and high reliability, at both the module and system levels of integration. He is also co-managing perovskite PV cell and manufacturing technology projects, with an emphasis on performance validation and bankability.

Before joining SETO, Allan was a scientific fellow and technology director at First Solar, working in the areas of CdTe cell, module, and system reliability and advanced module materials and designs. He concurrently worked as an Adjunct Professor at Bowling Green State University, teaching courses in renewable energy technology and sustainability. Allan holds a B.S. in Electrical Engineering, an M.S. in Materials Engineering, and a Ph.D. in Materials Engineering Science from Virginia Polytechnic Institute and State University (Va Tech). His graduate work focused on thermal management of high power, high voltage electronics and GaAs power amplifier reliability.