Solid-State Energy Conversion from Heat to Electricity Request for Information (RFI)

The Defense Advanced Research Projects Agency (DARPA) Defense Sciences Office is issuing Request for Information (RFI) DARPA-SS-27-01 to explore the current state of the art and technological limitations of solid-state direct thermal-to-electric energy conversion. This initiative focuses on systems that convert temperature differentials into electrical energy without the use of mechanical moving parts, such as turbines or pistons. The primary objective is to gather quantitative data on performance across various operating temperatures, identify limiting factors, and determine the most viable use cases to inform the planning of future research and development programs. This RFI is for planning purposes only and does not constitute a formal solicitation for proposals. Interested parties must submit unclassified responses by 4:00 p.m. Eastern on November 23, 2026, via email to DARPA-SS-27-01@darpa.mil. Submissions must adhere to specific formatting guidelines, including a 12-point font and a structured layout consisting of a cover sheet, a five-page technical description, a two-page bibliography, and a one-page summary of prior research. Respondents are encouraged to include technical models, test data, and the current Technology Readiness Level (TRL) of their technologies, while ensuring any proprietary information is clearly labeled.