MIT Scientists Find a Nuclear Fuel Design that Is Safer and More Efficient

Published December 1, 2006

A new fuel design created by scientists at the Massachusetts Institute of Technology (MIT) promises to increase nuclear power output by 50 percent at existing plants, MIT announced on September 20.

After three years of research and testing of next-generation fuel technology, MIT scientists discovered that forming uranium into the shape of hollow tubes rather than solid cylinders allows for more efficient energy exchange and safer operations.

Currently, uranium is formed into solid, cylinder-shaped pellets of less than an inch in diameter. In a nuclear reactor, fission releases a tremendous amount of energy in the form of heat that turns water into steam. The steam is then captured and funneled to power turbines that generate electricity.

Lower Temperatures Possible

The MIT scientists discovered that forming uranium into hollow tubes prior to fission allows more efficient energy exchange by allowing water to interact with a greater uranium surface area.

The new design also increases safety because it requires an operating temperature of only 700 degrees Celsius, as compared to 1,800 to 2,800 degrees Celsius under the current design.

Currently, a single pickup-truck load of uranium fuel is sufficient to run an entire city for a year. Under the new design, the same amount of uranium fuel will power that city for an extra six months.

Promising Nuclear Future

According to Pavel Hejzlar and Mujid Kazimi, the MIT scientists who made the discovery, the new fuel design should be available commercially within 10 years. The discovery is expected to form an important bridge to new technologies, such as pebble bed reactors, which are roughly 20 years away from commercial use in the United States.

“Nuclear power already was one of the most promising energy sources of the future,” observed Jay Lehr, Ph.D., science director for The Heartland Institute. “This breakthrough adds still more momentum to our most affordable clean-burning fuel source.

“Pebble bed reactors are the exciting future of nuclear power,” Lehr added, “but increasing energy output by 50 percent in existing reactors certainly bridges nuclear power’s present to its future. Nuclear power makes more and more economic and environmental sense with each passing day.”

James M. Taylor ([email protected]) is managing editor of Environment & Climate News.