NASA’s Science Mission Directorate is seeking information on Stirling power systems and technologies that could be developed into a space-based power system that would provide between 100-500 Watts of electricity for future deep space missions.

In partnership with the Department of Energy, a Request for Information (RFI) posted on June 3 seeks options for technologies that could lead to a generator, using radioisotope fuel, that would include one or more Stirling converters in an integrated system capable of providing reliable power for future planetary science spacecraft and, possibly, human exploration missions to Mars.

“We hope to receive detailed information about any robust and reliable Stirling converter designs that could power a science mission efficiently for at least a decade,” said John Hamley, manager of the NASA Radioisotope Power Systems (RPS) Program, based at NASA’s Glenn Research Center in Cleveland. “We look at this RFI as a way to reinvigorate our current Stirling technology development program, and use the best current ideas from governmental organizations and industry.  We hope to infuse what we have learned while operating these highly efficient systems for thousands of hours in the laboratory.”

As outlined in the RFI, the key information being sought by NASA includes descriptions of existing Stirling systems that could be relevant, the configuration and physical properties of such systems, related testing and performance data, the scalability of the systems and technologies, and the responder’s experience in manufacturing related space flight-quality hardware. Responses to the RFI are due by August 5, 2015. Since this is not a request for proposals, quotations or bids, NASA will not respond to submitters of information under this RFI.

“The ultimate goal is a Stirling radioisotope power system, or a set of modular options, that would provide robustness, and reliability—without maintenance—for the many challenging deep-space and planetary surface missions envisioned by the scientific community over the next 2-3 decades,” Hamley said.

In support of this RFI, a Stirling Technical Interchange Meeting (STIM) will be held on June 29, 2015, at the Ohio Aerospace Institute in Cleveland. Those interested in participating are encouraged to register by June 25. Registration materials and the draft agenda for the STIM are posted on the internet with the full RFI. The STIM agenda includes a review of NASA RPS Program accomplishments and plans for Stirling power technology, opportunities for discussion, and time for attendees to present non-proprietary information to the community.

A recent in-depth study conducted by NASA’s RPS Program found that future Stirling systems in the power range cited in the RFI are well matched to the current range of mission concepts identified in recent planetary science community assessments and proposal cycles, such as the 2011 Decadal Survey for planetary science by the National Academy of Sciences.

To view the complete RFI and learn more about the Stirling Technical Interchange Meeting, visit: 

To learn more about NASA Glenn, visit: