TTU energy experts working to lower costs, increase efficiency in electric power

Interested in tapping into local expertise, the Department of Energy is looking to Tennessee Tech University for analysis that can contribute to energy conservation and efficiency.

Through the State Energy Program, the DOE recently awarded two of the state's five projects to Tennessee Tech: one features a feasibility study of superconducting cables; the other will provide technological and manufacturing assessment of fuel cells.

"To be awarded two of the five projects this year shows we are receiving recognition for the quality of research we conduct at the university," said Sastry Munukutla, director of TTU's Center for Electric Power.

Fuel cell research offers an opportunity to address two pressing issues for the nation: U.S. dependence on foreign oil and pollution reduction. Because fuel cells use hydrogen and oxygen to produce heat to generate electrical power, they emit no pollution, only water. But fuel cells are expensive to produce, and cost is a major drawback hindering their commercial use. 

Three TTU mechanical engineering faculty members, associate professors Glenn Cunningham and Mark Jackson, and assistant professor John Zhu, are collaborating on research to reduce fuel cell production costs while maintaining the quality of current cells.
Cunningham describes a fuel cell as a sandwich of plates, including costly graphite plates. The TTU team will work with thin metallic plates, which are less expensive than graphite and amenable to high volume, low-cost manufacturing methods, such as stamping. 

The project fits Tennessee Tech's capabilities. Jackson, a former University of Cambridge research fellow and lecturer at the University of Liverpool, has experience with new manufacturing technologies and will oversee the stamping process. 

Zhu, who has an extensive research and work background in coatings, will test the integrity of the coatings on the metallic plates. A quality coating protects the metal from corrosion that interferes with cell performance. Also, Zhu conducted post-doctoral research at Oak Ridge National Laboratories, where sample plates will be manufactured.

Cunningham, who has a concentration of research in the electric power industry, focuses on collaborating with industry and institutions to pool talent and compete for federal funding. In the fuel cell project, ORNL will manufacture plates; Dana-Plumly Corp. of Paris, Tenn., will seal the plates, the University of Minnesota will provide 2,000 hours of fuel cell testing, and TTU will analyze the coating before and after testing to evaluate coating performance.

"This kind of collaboration focuses the talents and resources of universities and industry in the right direction," said Cunningham. "Instead of competing, we are concentrating on long-term successes through sharing our expertise."

In the same spirit, Prit Chowdhuri is looking to collaborate with various distributors of electric power in Tennessee and Oak Ridge National Laboratory to study the feasibility of superconducting cables to meet increased demands for power.

Again, the bottom line is reducing costs. Now, the unsightly power lines stretched across your neighborhood carry alternating current, the form of current used in homes and business. Chowdhuri says superconducting cables carrying direct current would be more efficient and cut the cost of transmission in half. Of course, the DC has to be converted, and converters historically have been too expensive to make using DC feasible.

"The bottleneck was the conversion of DC into AC you can use, but so much progress has been made on reducing the cost of converters, it's time to look at the advantages and possibilities of using DC," said Chowdhuri. 

His inspiration came from looking at German efforts to develop DC transmission in 1940s, and his experience in superconductivity was earned during his work at Los Alamos National Laboratory.

"Most currents encounter resistance in some form during transmission," said Chowdhuri. "Superconductivity is the state at which all resistance is lost and the current can flow freely and more efficiently."

DC would require half the lines used by AC, thus cutting the cost in half, and would be underground to improve the aesthetics of cities and neighborhoods. Underground lines would also reduce repair costs incurred when overhead lines are damaged by lightning, wind and toppled trees.