Millennium Cafe with William Bahnfleth and Linxiao Zhu

“The Cold of Outer Space as an Energy Resource: Using Light and Heat for Cooling and Electricity” – Part II in the Energy University Series Linxiao Zhu | Mechanical Engineering Every object at a finite temperature emits thermal radiation, ranging from sunlight, incandescent lighting, to blackbody radiation from human bodies which can be detected in thermal cameras. Nanostructured materials allow new kinds of light-matter interaction, allowing for tailoring various properties of thermal radiation. Controlling thermal radiation holds the key to new energy applications. This talk will briefly introduce our group’s passion on tailoring thermal radiation for energy applications, ranging from heat-to-electricity conversion across a nanoscale gap, utilization of the coldness of the outer space for passive cooling, to active refrigeration using light, enabled by nanocalorimetry, nano devices, and photonic design. “Shining a Light on Airborne Infection Control – Germicidal Ultraviolet Air Disinfection Systems” William Bahnfleth | Architectural Engineering The germicidal properties of certain wavelengths of light were first reported in the late 19th century. Ultraviolet C (UVC), is particularly effective at damaging the DNA and RNA of microorganisms of all types, preventing them from replicating. Technologies based on UVC have been used for nearly a century to help control airborne infectious disease outbreaks, but interest in them has spiked as a result of the COVID-19 pandemic. This presentation will briefly summarize our studies of ultraviolet germicidal irradiation systems for buildings, including recent studies focused on COVID-19 risk mitigation, and identify areas of need for further multidisciplinary research.