Increasing energy needs in cities are also coupled with higher temperatures and more heat waves, which are influencing the architecture and operations of buildings. This trend is forcing scientists to seek solutions to reduce energy use while maintaining comfortable conditions for people. The field of building physics is becoming one of those areas where collaboration among engineering, climatology, materials science, and simulation methods is increasing. Efficient thermal energy storage, urban climate modeling, and building envelopes are gaining weight in both national energy policy and decarbonization strategies. In the scientific context of building physics, one of the French scientists working in this field is Frédéric Kuznik.
Frédéric Kuznik is a Professor of Civil Engineering at the National Institute of Applied Sciences of Lyon (INSA Lyon), where he is an Exceptional Class Professor. He is also a researcher at the Center for Energy and Thermal Sciences of Lyon, or CETHIL, a joint research laboratory shared by CNRS, INSA Lyon, and Claude Bernard University Lyon 1. Between 2018 and 2022, he directed CETHIL, and from 2015 to 2025, he led the joint EDF-CETHIL laboratory dedicated to Highly Efficient Energy Buildings. Since November 2023, Kuznik has represented France on the Executive Committee of the International Energy Agency Energy Storage Technology Collaboration Program, contributing to international work on thermal energy storage technologies.
Unlike many engineering careers that remain focused on a single specialty, Kuznik’s research gradually expanded across several connected fields. After studying civil engineering at the École normale supérieure Paris-Saclay, he obtained the French Agrégation in Civil Engineering in 2000, then completed a research master’s degree and a doctorate at INSA Lyon. His doctoral work, defended in 2005 under the supervision of Brau and Rusaouën, examined airflow within ventilated cavities using experimental measurements and numerical simulations. The topic addressed practical questions about ventilation efficiency. Also, it established the computational methods that later became central to his broader research program.
One direction that followed involved computational fluid dynamics for buildings and cities. Kuznik became one of the researchers applying lattice Boltzmann methods to building science, particularly through graphics processing units capable of handling large numerical calculations. The approach allowed researchers to simulate airflow, heat transfer, and urban wind behavior with greater computational efficiency. These methods later supported studies of urban microclimates, street canyons, and neighborhood-scale heat exchanges. His research group also combined lattice Boltzmann simulations with Large Eddy Simulation techniques to improve understanding of airflow inside mechanically ventilated buildings and dense urban environments.
Another area closely associated with Kuznik concerns phase change materials used within building envelopes. These materials absorb and release heat as they change physical state, allowing walls or other building components to moderate indoor temperatures without additional energy input. His 2011 review article in Renewable and Sustainable Energy Reviews became one of the most cited publications in this area, accumulating several hundred citations over the following decade, according to major citation databases. A revised review published in 2021 reflected the rapid expansion of research into practical building applications and updated developments in material performance and integration techniques.
Thermal energy storage emerged as a broader theme in Kuznik’s work through research on adsorption and thermochemical storage systems. The purpose of such technologies is to provide a way to store thermal energy over time through reversible chemical or physical processes, rather than the traditional use of water vessels. His research included the examination of materials such as zeolites, magnesium sulfate, lanthanum chloride, strontium bromide, and ettringite, as well as laboratory-scale prototypes with an intermediate level of technology readiness. These developments later became the subject of interviews and conference presentations discussing future seasonal heat storage technologies.
Beyond materials research, Kuznik has contributed to large-scale energy modeling. Within the EDF and CETHIL partnership, his team developed the MoDEM platform to predict heating and cooling demand across buildings and districts, accounting for local urban climate conditions. More recent publications also explored machine learning techniques for forecasting residential electricity demand by combining physics-based models with data-driven methods. Rather than replacing physical modeling, these studies examined ways to improve prediction accuracy, especially during peak demand periods when forecasting becomes more difficult.
Climate adaptation has also become an increasingly visible theme within Kuznik’s research. As European cities experience more frequent periods of extreme heat, his group has investigated overheating inside residential buildings and the effects on vulnerable populations. Recent studies combined building simulations with thermophysiological models to evaluate heat exposure among elderly residents living in different housing conditions. The research reflects a wider shift within building physics from energy efficiency alone toward questions of resilience, occupant health, and climate adaptation.
Alongside research, Kuznik has remained active within international scientific organizations. He has coordinated or participated in numerous French National Research Agency projects, European collaborations, and International Energy Agency activities. His international partnerships include institutions in China, Japan, South Korea, and Morocco. He also chaired the scientific committee of Enerstock 2024, the International Energy Agency conference on energy storage held in Lyon, bringing together researchers and industry specialists working on thermal storage technologies.
His academic service extends beyond research projects. Kuznik serves on the editorial boards of journals including Energy Storage, Sustainable Cities, and Society Advances. He has also reviewed proposals for organizations such as the European Research Council, the European Innovation Council, the French National Research Agency, and several national research funding agencies across Europe. These activities place him within the peer review process that supports research evaluation beyond his own publications.
Recognition of Kuznik’s work has come largely through scientific institutions rather than public awards. Since 2020, he has appeared each year in Stanford University’s widely referenced database identifying the world’s most cited researchers based on standardized citation indicators. In 2024, he was appointed a Distinguished Scientist under the Chinese Academy of Sciences President’s International Fellowship Initiative. In June 2025, INSA Lyon awarded him its Research Medal. Citation databases also reflect the reach of his publications. Google Scholar reports more than 11,000 citations, while Scopus records an h-index above 40. These figures place his work among the more visible contributions within building physics and thermal energy storage research.
Currently, Kuznik’s research includes building materials, simulation models, urban climates, heat storage, and energy systems. Not following a specific path of research topics, his research links all of these topics around the broader theme of how buildings can use less energy while responding to climate change. This is how the scientist is expected to develop in terms of scientific production and international collaborations on energy systems in the future.
