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

The Defense Advanced Research Projects Agency (DARPA) Defense Sciences Office is requesting information on solid-state direct thermal-to-electric energy conversion technologies, with responses due by 4:00 p.m. Eastern on November 23, 2026. This is an RFI for information gathering and program planning; responses are voluntary and non-binding and do not constitute offers.

DARPA seeks quantitative technical information across three primary areas: current capability (efficiency of realizable solid-state converters today, including operating parameters, temperature limits, and size/weight/power specifications), technology potential (achievable performance improvements with supporting evidence on how technical barriers limit current performance and how solutions could address them), and applications (use cases that would benefit most from improved conversion, including quantitative efficiency, power output, or size/weight/power thresholds that would make solid-state systems preferable to alternatives).

The RFI covers thermoelectric generators, thermionic energy converters, thermophotovoltaic converters, alkali metal thermal-to-electric converters, and hybrid approaches. Responses should include a one-page cover sheet, five-page technical description, two-page bibliography, one-page description of prior research and experimental capabilities, and an optional graphic overview slide. All materials must use 12-point font, single-spaced format in MS Word or PDF, and be submitted to DARPA-SS-27-01@darpa.mil. Mike McDonald is the Program Manager point of contact. DARPA welcomes submissions from universities, private and public companies, FFRDCs, UARCs, and government laboratories across all technology readiness levels. The procurement spans basic research in defense R&D services (PSC AC11).