SBIR Phase I: Upscaling Air-Bridge Thermophotovoltaics for Thermal Batteries

The broader/commercial impact of this Small Business Innovation Research (SBIR) Phase I project lies in advancing reliable, energy efficient, and modular electricity generation through thermophotovoltaic cell technology. Unlike conventional dynamic heat engines, which include moving parts and heat exchangers, thermophotovoltaic cells convert high-temperature thermal energy directly into electricity using a solid-state device, offering rapid load-response, greater modularity, and less down time. Recent innovations in thermophotovoltaic design enable these cells to generate up to 500 times more electricity per unit area compared to rooftop solar, unlocking cost-effective use of high-quality semiconductor materials and supporting distributed energy production in industrial settings. By integrating thermophotovoltaics with modular thermal batteries, facilities can power operations with low-cost energy and support the electric grid with flexible storage solutions, a critical capability as variable sources and loads increasingly enter the energy landscape. This project aims to develop highly efficient thermophotovoltaic modules for on-site combined heat and power systems, addressing a multi-billion-dollar market. Societal benefits include reductions in primary energy consumption and energy costs, job creation at manufacturing facilities where this technology will be scaled up, and development of a semiconductor technology critical to defense and civilian applications. This Small Business Innovation Research (SBIR) Phase I project focuses on development of air-bridge thermophotovoltaic modules for efficient conversion of high-temperature thermal energy to electricity. The project exploits a novel air-bridge architecture that reflects over 98% of waste infrared photons back to the thermal source, thus narrowing the transferred spectrum to maximize usable energy and improving heat-to-power conversion by up to 30%. The principal problem addressed by this technology is overcoming the limited efficiency and temperature range of traditional thermophotovoltaic devices, which has restricted practical deployment. Research objectives are designed to build confidence in this technology among thermal battery system developers and vendors, which are the intended customers and commercialization partners. These objectives include scaling fabrication to wafer-scale modules, building and testing modules under relevant use conditions, and demonstrating modules that maintain high efficiency at high power densities. The technical advances position air-bridge thermophotovoltaics as a scalable solution for industrial power and energy storage, with a clear path toward commercial pilot projects and widespread market adoption. This award reflects NSF's statutory mission and has been deemed worthy of support through evaluation using the Foundation's intellectual merit and broader impacts review criteria.