The Laboratory for Thermal Transport and Storage (LET+S) seeks to better understand fundamental fluid dynamic and heat transfer processes, and use this insight to make more efficient thermal energy systems. Our lab uses a combination of experimental and modeling techniques to make these advances, which feed into a variety of applications including nuclear power production and building energy systems. Our lab is part of a collaborative research group at University of Wisconsin – Madison called the Solar Energy Laboratory.
At the LET+S, we lead and contribute to projects that:
- Enable us to shift and shave building electrical loads with thermal energy storage, allowing for a more renewable and sustainable electricity grid.
- Increase the efficiency of thermal equipment to reduce the energy required for a variety of processes, from industrial manufacturing to home heating and cooling.
- Facilitate the transition to electrified buildings by developing heat pump systems that can work in a wide range of climates
- Improve reactor safety in nuclear power production
Our overall goal is to develop safe and effective thermal systems that provide a benefit to society while helping our world transition to a low-carbon energy future.

Lab News

Presented two-phase flow work at GRC
Dr. Mahvi and Joe Farrell presented some of our work on annular two-phase flow at the Micro and Nanoscale Phase Change Gordon Research Conference in January.
February 3, 2025
Mahvi awarded funds to advance cold-climate heat pumps
Mechanical Engineering Assistant Professor Allison Mahvi was recently selected for a $2M award from the Department of Energy to develop a more sustainable heat pump that can replace existing, less efficient boilers in older buildings. …
October 5, 2024
Naleah Boys awarded research fellowship
Naleah was awarded the Faustin Prinz Undergraduate Research Fellowship. The fellowship supports undergraduate Mechanical Engineering and Engineering Mechanics students who want to develop a research project with ME or EM faculty, get access to cutting-edge …
July 1, 2024
Welcomed Jack to the group!
We are excited to welcome our newest member, Jack Prout, to the group! Jack is a Masters student in Mechanical Engineering. He received her BS in Mechanical Engineering from University of Wisconsin in 2024. His …
July 1, 2024- More Posts