Harnessing Terrestrial Thermal Photon Sources for Clean Energy and Clean Water

17 April 2020 11:00 - 12:00

Eastern Time (US & Canada) (UTC -05:00)

I will discuss challenges and opportunities in controlling and harvesting the radiative energy of terrestrial thermal sources. Unlike solar radiation, thermal emission from terrestrial sources can be controlled and tailored via optical design. For example, bringing emitters and absorbers into the regime of near-field coupling allows breaking many fundamental limits that stymie development of high-efficiency solar energy conversion platforms. On the other hand, long distances travelled by propagating infrared photons through the Earth’s atmosphere allow using the ultra-cold outer space as the heat sink for the terrestrial energy conversion engines. I will outline design strategies for one such engine, a ‘reverse solar cell’ system – also known as a thermoradiative cell – that can generate electric power via non-equilibrium thermal emission. The technological area where the importance of the terrestrial thermal radiation control really hits home is in personalized thermal management and solar water treatment. I will discuss our work on engineering new fabrics that achieve passive temperature control of human body via spectrally-selective scattering of photons across visible and infrared spectral ranges and on harnessing thermal radiation for water distillation and disinfection.