New Refrigeration Cycle

This cool new approach to refrigeration could replace harmful chemicals |  Ars Technica

Drew Lilley and Ravi Prasher have developed a new thermodynamic cycle, the ionocaloric refrigeration cycle! This cycle uses differing ion concentrations in materials to induce phase change, enabling cooling without the use of harmful refrigerants. This new concept has lots of potential, and we're excited to see where it goes! This technology was novel enough to warrant a Science paper, and you can read more here.


Group Lunch at Cornerstone

Thermal energy group members sitting at a table together for a picture at Cornerstone

Ravi recently announced that he has accepted the CTO position at Bloom Energy, and that he will be switching jobs at the end of the month. He took the whole group out to Cornerstone for a chance to get everybody together before he leaves. We had a great time, and the food and drinks were fantastic, and we wish Ravi the best in his new position! Thanks for all that you've done for all of us!


Goodbye Qiye!

Thermal energy group members standing together for a picture on the cafeteria patioToday, our group had a brunch get-together to say goodbye to Qiye Zheng, who's been a very important member of our group for 3 years. During his time here, Qiye has performed groundbreaking research in thermal metrology, and worked with and mentored lots of researchers and students. He is leaving to be a professor at the Hong Kong University of Science and Technology. We'll miss you Qiye, and best of luck in your future endeavors!


Publication on Phase Change Materials Covered by American Institute of Physics

Image showing a box on the left depicting Sensible Heating, and illustrating heat capacity and thermal cinductivity, The center Blue box shows the Phase Change Material and the Latent heat of fusion, supercooling, and nucleation. The far right box depicts the thermochemical material, and the enthalpy and entropy of the reaction.

Delighted to announce that our group's latest publication, Phase change materials for thermal energy storage: A perspective on linking phonon physics to performance, authored by Drew Lilley et al, was recently covered by the American Institute of Physics.

This paper describes advances that our work has made in understanding the fundamental physics of phase change materials used for energy storage.

The link to the full text of the paper can be found here:

Way to go, Drew and team!


Thermal Energy End-of-Year Picnic

Image of lab group members lined up in front of some foliage, smiling.

Just before the winter break, the Thermal Energy Group had its first official get together since before the beginning of the pandemic. We gathered at Tilden Regional Park and shared pizza, drinks, conversation, and a little bit of sunlight. Most of us had not crossed paths much over the last couple of years, so this was a much needed chance to reconnect in person.

Many more like this coming in the near future! 


New Postdoc Opportunity: Catalysis and Thermochemical Reactor Design

We have an opening for a postdoc with expertise in the field of chemistry and chemical engineering, with a particular focus on catalysis and thermochemical reactor design. 
The Project: Cost-effective decarbonization of heat, which is the dominant source of energy for the industrial and building sector worldwide, is a grand scientific and technological challenge. Currently natural gas is the dominant source of heat in these sectors. Although CO2-free hydrogen is being considered as a potential alternative, infrastructure challenges related to transport and storage of hydrogen are enormous (e.g., Majumdar et al., Joule 5 (8), 1905-1908). Natural gas infrastructure and storage are already in place. Therefore, cost-effective synthetic natural gas derived from COcaptured from either point source or direct air capture combined with CO2 free hydrogen is a very lucrative option.
In this project we propose to use the Sabatier reaction to create synthetic natural gas. Since the Sabatier reaction is highly exothermic, the released heat can then be used to offset the energy requirement for either carbon capture or hydrogen production, making this overall process and system cost-effective. As the Sabatier reaction is highly temperature sensitive, the major associated challenge is related to temperature control. The higher temperature results in poisoning and sintering of catalysts making them inactive, thus lowering the yield.

This Postdoctoral Fellow will contribute to catalyst and overall reactor development to improve the reaction rate at lower temperatures, while preserving high activity and stability in an operating window up to 400 oC. 

For more information or to apply, please contact Dr. Suman Kaur at


New Thermal Energy Group Temperature Record Set!

Using our new infrared pyrometer, we set a new Thermal Energy Group record this week, measuring temperatures above 2000° C for the first time! The high temperature chamber is used to study hydrogen production by methane pyrolysis and to investigate high-temperature thermal energy storage materials. The record was set by Nate Weger, Lin Yang, and Clement Messeri using a C-type thermocouple, breaking the record of 1700° C set by Nate Weger and Mahmoud Elzouka. 


We Have A New Postdoc! Thermal Energy Group Welcomes Youngsup Song

Youngsup received his B.S. and M.S. in Mechanical Engineering from Yonsei University, where he developed nanomaterial-integrated MEMS devices. He received his PhD from MIT, where he focused on mechanistic understanding and enhancing pool boiling heat transfer, via surface property and structure design, at the Device Research Lab (DRL). Prior to his PhD study, he also worked at Korea Institute of Materials Science (KIMS) in the Electrochemistry Department. 

Outside of the lab, you might find him taking a walk with his family around the campus, playing soccer, or working out in the gym. Welcome, Youngsup!

Photo of Youngsup Song


New Interns on Board!

This fall we welcome two new interns to our group. UC Berkeley undergraduates Rushabh Shah and Clément Messeri will be working on a project to develop high temperature materials (1,000 C to 2,000 C) that can store thermal energy for tens to thousands of hours, enabling the integration of intermittent renewable sources of energy into industrial manufacturing and the power grid. This work will help to decarbonize the nation’s energy economy.

Welcome Clément and Rushabh!