Today’s unprecedented energy needs are fueled in large part by the low energy efficiency of our engineered systems and infrastructures. The rapid modernization of developing countries and the continuous growth of world population are bound to quickly accelerate global energy consumption and may soon lead to an unsustainable balance between current energy sources, an increasing demand worldwide, and the inefficiency of technologies for energy production and usage. The figure above describes how energy supplies match to sectors (Residential, Commercial, Industrial, and Transportation), together with the corresponding waste energy. More than 57% of US energy production is wasted mostly in the form of heat.
One of the key solutions for solving the impending energy crisis is the development of new technologies that enable the design and implementation of energy efficient systems. The thermal management team addresses this challenge through the development of highly efficient nano-engineered thermoelectric materials that permit the production of electricity by harvesting wasted heat released by power plants or combustion engines. Two distinct classes of materials are investigated. The first class is based on a recently discovered glassy phase with extremely low thermal conductivity and unusually high electrical conductivity. Controlled nucleation of nanocrystals in this phase permits the system to increase its electronic conductivity while still scattering phonons (lower heat transport), thereby providing unprecedented figure of merit for thermoelectric efficiency. The second class involves nanostructuring two-dimensional systems such as graphene and boron-nitride to design cutting-edge materials that demonstrate ballistic phonon transport, or as thermal diodes that enable the directional control of flow and recovery of wasted heat.
The thermal management team is also actively involved in the design of thermal fluids (e.g. heat transfer fluids) for concentrated solar power plants (CSP). The team focuses on molten salt thermal fluids composed of compounds that are largely available either with direct reserve on the earth or with the possibility of being chemically synthesized with materials abundant on earth. Increasing the efficiency of CSP requires operation at high temperature. We concentrate on thermal fluids with high stability at high temperatures of no less than 800C, as well as with sufficiently low melting point (no higher than 250C) for thermal storage reasons. In addition, we are exploring thermal fluids that are chemically compatible with the materials used in the CSP infrastructures such as the materials of piping, pumping, and heat exchangers.
Support is provided by industry and Federal agencies.
P. Lucas (MSE)
K. Muralidharan (MSE)
W. Beck (Physics)
S. Seraphin (MSE)
Qing Hao (AME)
B.G. Potter (MSE)
Peiwen Li (AME)
D. Gervasio (ChEE)