A US multi-organisation team led by Morgan State University, in collaboration with aerospace and defence technology company Northrop Grumman, Pacific Northwest National Laboratory (PNNL), and nuclear energy company Project Omega, has been awarded a $3.37m contract by the Defense Advanced Research Projects Agency’s (DARPA’s) Rads to Watts programme.
The programme centres on the development of a new class of radiovoltaic devices that significantly increase power density, which is the amount of power produced per mass of the device, measured in Watts per kilogram (W/kg). Achieving high power density, while maintaining a long operational lifetime, may open up new capabilities.
Applied Research Associates (ARA) and Widetronix are participating via the associated SYMPHONEE project. They provide the vital bridge between Morgan State University’s academic research and the industrial-scale manufacturing required by DARPA.
SYMPHONEE – Strontium-Yttrium Multi-junction PIN-based High-Density Output Nano-system for Extreme Environments – is the name of the specific technical project being executed under the DARPA “Rads to Watts” contract. It uses a multi-junction silicon carbide (SiC) PIN semiconductor structure to maximise power density.
The system bypasses traditional thermal conversion. It captures and converts beta radiation directly into electricity using beta-emitting isotopes – strontium-90 and yttrium-90 – which are recovered from used nuclear fuel and legacy Cold War nuclear waste.
The project divides its execution across specialised organisations PNNL oversees laboratory validation for radiation tolerance and conversion efficiency. Northrop Grumman leads the AI-driven simulations, high-performance computing, and survivability analysis under intense radiation fluences. Project Omega handles the chemical separation and extraction of the strategic isotopes from nuclear waste. ARA and Widetronix provide specialised technical support to manufacture ultra-thin semiconductor layers designed to prevent radiation-induced degradation.
The primary goal is to achieve a step-change improvement in Watts per kilogram (W/kg). The resulting maintenance-free “nuclear batteries” are intended to power deep-space probes, autonomous undersea infrastructure, and remote tactical military sensors for decades without refuelling.
“Morgan State University is honoured to lead this effort,” said Professor Michael Spencer, the technical lead for the project. “Our team is pushing the boundaries of radiovoltaic technology, developing high-power, long-life systems that were not previously achievable. By integrating advanced materials, device engineering, and nuclear science, we are laying the foundation for a new generation of persistent power systems for extreme environments.”
Dr Stafford Sheehan, CEO and founder of Project Omega, noted “Our mission is to turn what has historically been treated as waste into a strategic energy asset. Rads to Watts provides a clear demonstration of how recovered isotopes can power critical systems for years, without needing to manage the logistics around constant battery replacement.”
Northrop Grumman is accelerating design optimization and enabling rapid iteration across complex material and device configurations. “Persistent power is a foundational requirement for next-generation defence systems, and this programme strives to deliver resilient, long-duration energy solutions that can operate where traditional systems cannot,” said Matt Hicks, Director for foundry, advanced packaging and test at Northrop Grumman. “Our aim is to constantly disrupt our own technology, building on our past to transform for the future.”
