Phoenix Nuclear Labs (PNL) was founded by Dr. Greg Piefer in 2005 with the vision of commercializing near-term nuclear applications in order to advance state-of-the art fusion technologies with the ultimate aim of clean and abundant fusion power. PNL has developed several proprietary technologies that have been purchased by the US Army, the US National Nuclear Security Administration, the University of Wisconsin, the Morgridge Institute for Research, and SHINE Medical Technologies. Through the development of these technologies, PNL has become a global leader in accelerator-based fusion technology, nuclear particle generators, and high voltage power supplies.


Dr. Ross Radel, President

Dr. Radel holds a PhD in Nuclear Engineering from the University of Wisconsin-Madison. He previously worked as a Senior Member of the Technical Staff at Sandia National Laboratories and has extensive experience with nuclear reactors and advanced power conversion systems that are directly applicable to PNL’s core technology. His previous research at the University of Wisconsin laid the groundwork for PNL’s techniques for detecting clandestine material, including highly enriched uranium. Dr. Radel joined PNL in 2010 and replaced Dr. Piefer as president in July of 2011.

Dr. Evan Sengbusch, Vice President, Business Development

Dr. Sengbusch holds a PhD in Medical Physics and an MBA from the University of Wisconsin-Madison. He has secured funding from the National Science Foundation, the National Institutes of Health, and the Department of Defense and has worked as a consultant for several early-stage technology companies with applications including ultrasound imaging, vital signs monitoring, radiation therapy, and medical radioisotope production. He previously worked in the Accelerator Technology Division at CERN and at the University of Iowa Positron Emission Tomography Imaging Center.

Mr. Steve Books, Vice President, Operations

Mr. Books is a seasoned executive with extensive experience in General Management and Operations in entrepreneurial manufacturing organizations that required leadership to accelerate from early stage to the next level of business success. As part of Marquette Medical Systems, Steve was responsible for the P&L of the $200 million Cardiology division after filling a number of manufacturing and engineering management roles. GE purchased MMS in 1999 and Steve began managing Global Operations and Supply Chain for GE-Marquette. More recently, Steve was responsible for R&D, Service, Manufacturing and H/R as COO of TomoTherapy, an innnovative radiation therapy device manufacturer for cancer treatment.

Dr. Tye Gribb, Vice President, Research and Development

Dr. Gribb has over 20 years’ experience developing technology for high technology companies. He was the co-founder of Imago Scientific Instruments (now part of Cameca Instruments Corporation) where he led the development of the Local Electrode Atom Probe (LEAP), Imago’s flagship product, from initial sketches through commercialization. Dr. Gribb has wide-ranging design, fabrication, and scientific analysis expertise focused on the development of ion beam and other high-energy systems. He is the author of numerous papers and patents covering a wide range of technical innovations. Dr. Gribb holds a PhD from the University of Wisconsin-Madison in Metallurgical Engineering.

Ted Staub, PE, Director of Engineering

Mr. Staub holds an MS in Electrical Engineering from Drexel University and has thirty years of experience in designing and building reliable high voltage power supplies. He has designed and built air-to-air missile electronics for Raytheon, airborne high voltage power supplies for Texas Instruments and the US Navy, and the power subsystem for two NASA missions to Mars for Lockheed Martin. Mr. Staub has been a member of the IEEE for 31 years and is a registered professional engineer.

Dr. Greg Piefer, Founder

Dr. Piefer founded Phoenix Nuclear Labs in 2005 following the completion of his PhD in Nuclear Engineering from the University of Wisconsin-Madison. Currently, he serves on the PNL Board of Directors and is the CEO of SHINE Medical Technologies, a spin-off from PNL that will produce medical radioisotopes with PNL’s core accelerator technology. Previously he served as Chief Technical Officer to Gillware Inc., a leading data recovery and remote data backup company.

Scientific Advisory Board

Dr. Thomas “Rock” Mackie

Dr. Mackie currently serves as the Director of Medical Devices for the Morgridge Institute for Research. He was previously a Professor of Medical Physics, Human Oncology, and Engineering Physics at the University of Wisconsin-Madison and the Chairman of the Board of Directors of TomoTherapy, Inc. Dr. Mackie was the founder of Geometrics Corporation (acquired by Philips) and TomoTherapy (acquired by AccuRay). He has authored more than 130 peer-reviewed publications and is an author on more than 25 patents. Dr. Mackie currently serves of the Boards of BioIonix, Cellectar, ESCAPX, and Compact Particle Acceleration Corporation. He holds a PhD in Physics from the University of Alberta.

Dr. Harrison Schmitt

Dr. Harrison Schmitt previously served in the US Senate and was the Lunar Module Pilot on the final Apollo 17 mission to the moon. He also served as a Mission Scientist in support of the Apollo 11 mission. He was the only scientist and the last of twelve men to step onto the Moon. He continues to work in science, aerospace and business, and chaired the NASA Advisory Council from 2005-2008. Dr. Schmitt is the author of “Return to the Moon” (Copernicus-Praxis 2006), a book advocating a private sector initiative to develop lunar helium-3 fusion power for use on Earth.

Dr. Paul M. DeLuca, Jr.

Dr. DeLuca is Provost and Vice Chancellor of Academic Affairs at the University of Wisconsin-Madison. He was the chair of the Medical Physics Department from 1987 through 1998 and holds an appointment as professor in the Departments of Medical Physics, Radiology, Human Oncology, Engineering Physics, and Physics. His research interests have concentrated on fast neutron dosimetry including production of intense sources of fast neutrons, determination of elemental neutron kerma factors and application of microdosimetry to radiation dosimetry. He is also the chair of the Nonproliferation and International Security Division Review Committee (DRC) at Los Alamos National Laboratory. He earned a BS in physics and math and a PhD in nuclear physics from the University of Notre Dame.