UC Berkeley nuclear engineer whose expertise in molten salt and liquid metal systems shaped thinking on fusion blanket technology and tritium breeding — while advising national policy on fusion energy development.
Per Peterson is a professor of nuclear engineering at the University of California, Berkeley, where he has spent decades working on advanced heat transfer systems, molten salt technologies, and liquid metal applications relevant to both fission and fusion energy. His research bridges the gap between fundamental thermal-hydraulics and the engineering challenges of building practical energy systems.[1]
Peterson earned his doctorate from UC Berkeley and rose to become chair of the Department of Nuclear Engineering. His work has encompassed fluoride salt-cooled high-temperature reactors, pebble-bed reactor concepts, and — crucially for fusion — the liquid blanket systems needed to breed tritium fuel and extract heat from fusion reactors.[2]
One of Peterson's most significant contributions to fusion has been his research on molten salt and liquid metal blanket concepts. Fusion reactors require blanket systems that can absorb 14.1 MeV neutrons from deuterium-tritium reactions, breed tritium to sustain the fuel cycle, and transfer heat to power conversion systems — all while surviving intense radiation environments.[1]
His research group investigated the thermal-hydraulic behavior of these high-temperature fluids, characterizing heat transfer coefficients, flow stability, and corrosion behavior under conditions representative of fusion blanket operation. This work provided essential engineering data for reactor designers considering liquid blanket options.[3]
Peterson has served on numerous advisory committees shaping U.S. fusion energy policy. His participation in National Academies studies and Department of Energy advisory panels brought engineering pragmatism to discussions often dominated by plasma physics perspectives. He advocated for greater attention to the nuclear technology challenges of fusion — materials, blankets, tritium handling, and remote maintenance — arguing these engineering systems required sustained development programs comparable to those addressing plasma confinement.[2]
Peterson's parallel work on advanced fission systems, particularly fluoride salt-cooled reactors, created valuable intellectual cross-pollination with fusion blanket research. The materials compatibility challenges, tritium management issues, and high-temperature salt chemistry problems are shared between these domains, and Peterson's group contributed to both fields simultaneously.[3]
His involvement with Kairos Power, a company developing a fluoride salt-cooled fission reactor, further demonstrated the practical application of technologies originally studied in fusion contexts, illustrating the bidirectional technology transfer between advanced fission and fusion engineering.[1]