Military researchers eye converting nuclear radiation directly into high-power electricity for defense uses

ARLINGTON, Va. – U.S. military researchers are ready to approach industry for a program to convert nuclear radiation directly to electricity to provide long-term unattended power for military applications in which refueling and other support is impractical.

Officials of the U.S. Defense Advanced Research Projects Agency (DARPA) in Arlington, Va., issued a notification to industry last week on the future Rads To Watts project.

Rads to Watts will explore new approaches for converting nuclear radiation energy directly into electricity, without taking the interim step of converting radiation to heat before converting it to electricity.

The project focuses on radiation voltaics -- also called radiovoltaics -- which converts the energy from ionizing radiation directly into electricity using semiconductor materials. The radiation excites electrons and creates electron-hole pairs in the semiconductor to generate an electrical current.

Radiation to kilowatts

Specifically, Rads to Watts seeks to convert high-power nuclear radiation into kilowatts of electrical energy to create long-term high-power sources for military applications that must operate in harsh and remote areas.

Radiation-induced defects in radiovoltaics can degrade the performance and lifespans of today's radiovoltaics at the materials and device levels when exposed to high-power radiation sources.

Instead, Rads to Watts will encourage contractors to go beyond typical low-power radiovoltaic architectures and semiconductors with low-fluence tolerance for long-lived high power conversion.

This notice is for planning only, and does not yet constitute a formal solicitation, DARPA officials point out. Email questions or concerns to DARPA's Tabitha Dodson, the Rads to Watts program manager, at [email protected]. More information is online at https://sam.gov/opp/31682dd7e943437fac212aa395e949f6/view.