DARPA bets on nuclear-waste microgenerators to break drone power limits
DARPA’s Rads to Watts is funding Sr-90 nuclear-waste power cells targeting >10 W/kg and multi-year shelf life, with a prototype planned for early 2027—raising future endurance gains and regulatory burdens for European users.
Key facts
- DARPA “Rads to Watts” seeks lightweight radioisotope power cells and a proof-of-concept exceeding 10 W/kg with yearslong shelf life; reported $3.37m award supports the effort.
- Consortium roles: Morgan State University (prime/basic research), PNNL (nuclear materials/testing), Northrop Grumman and ARA (computational modelling), Project Omega (Sr-90 generator), Widetronix (semiconductor power converter).
- Prototype goal: working device by early 2027 at PNNL; key challenges include efficiency, long-term reliability, radiation effects, and safe, secure handling and deployment.
3 minute read
DARPA’s “Rads to Watts” programme is attempting to industrialise a long-known concept—direct conversion of radioactive decay into electricity—but in a form factor and power density that could be relevant to modern unmanned systems. The latest step is a reported $3.37m contract award aimed at producing a proof-of-concept device delivering more than 10 W/kg and offering a yearslong shelf life, positioning the technology as a complement or replacement for batteries in applications where depletion is operationally catastrophic or logistically prohibitive.
The team structure indicates a deliberate path from materials handling to defence-grade engineering. Morgan State University is the prime contractor for basic research, with Pacific Northwest National Laboratory responsible for nuclear materials and testing. Northrop Grumman and ARA are tasked with computational modelling to ensure the prototype meets performance standards. Project Omega will build the radioisotope power generator using strontium‑90, described as less hazardous than the plutonium‑238 historically used in many space radioisotope systems, while Widetronix is developing the semiconductor power conversion layer.
Operationally, the stated value proposition is endurance and resilience rather than peak power: persistent electricity for satellites, extreme-temperature operation, and “pain point” mitigation where battery failure equals mission failure. For drones, this is most plausibly relevant to long-dwell ISR, communications relay, unattended logistics beacons, or high-latency maritime surveillance nodes—missions where persistent low-to-moderate power can be decisive even if propulsion remains fuel-based or hybridised.
For Europe, the immediate implication is strategic: the US is investing in non-traditional power sources that could widen endurance differentials in contested ISR and space support, while also setting de facto standards for safety cases, secure handling, and radiation effects qualification. European procurement organisations and primes should anticipate future interoperability and export-control friction (radioisotope sources, supply chain traceability, and security requirements) and consider whether to pursue parallel R&D or niche adoption for remote sensors, Arctic/Baltic operations, and space-enabled defence services.
The programme’s own risk register is explicit: conversion efficiency, long-term reliability, radiation effects, and safe/secure deployment. A working prototype is targeted for early 2027 at PNNL, implying an 18-month risk-reduction window before any credible transition discussion for military systems.
Source: Defense One
