Electrical power generation from moderate-temperature radiative thermal sources

Moderate-temperature thermal sources (100 degrees to 400 degrees C) that radiate waste heat are often the by-product of mechanical work, chemical or nuclear reactions, or information processing. We demonstrate conversion of thermal radiation into electrical power using a bipolar grating-coupled complementary metal-oxide-silicon (CMOS) tunnel diode. A two-step photon-assisted tunneling charge pumping mechanism results in separation of charge carriers in pn-junction wells leading to a large open-circuit voltage developed across a load. Electrical power generation from a broadband blackbody thermal source has been experimentally demonstrated with converted power densities of 27 to 61 microwatts per square centimeter for thermal sources between 250 degrees and 400 degrees C. Scalable, efficient conversion of radiated waste heat into electrical power can be used to reduce energy consumption or to power electronics and sensors.