Sensors could monitor reactors in disaster

U.S. researchers say they've created self-powered sensors that could monitor a nuclear reactor in a disaster even when electrical power to the reactor fails. The research was prompted by the 2011 Fukushima Dai'ichi nuclear disaster in Japan, when the electrical power supply to the nuclear reactor failed during a severe earthquake and subsequent tsunami and rendered backup electrical generators, coolant pumps and sensor systems useless. The loss of power meant the plant's operators were unable to monitor the fuel rods in the reactor and spent fuel in the storage ponds. Penn State researchers have teamed with the Idaho National Laboratory to create a self-powered sensor capable of harnessing heat from nuclear reactors' harsh operating environments to transmit data without electronic networks, a release from the American Institute of Physics reported Tuesday. The sensors use a technology called thermoacoustics to create energy from the heat with a nuclear reactor. "Thermoacoustics exploits the interaction between heat and sound waves," Randall A. Ali, a graduate student studying acoustics at Penn State, said. "Thermoacoustic sensors can operate without moving parts and don't require external power if a heat source, such as fuel in a nuclear reactor, is available." The researchers will present their findings at the Acoustical Society of America's meeting this week in Kansas City, Mo.