Description: An opportunity to boost energy efficiency in homes and buildings exists through the design of functional radiative properties in glass and other building materials. Current surface materials ignore or take first-order approaches to complicated spectral behavior, leading to sub-optimal properties. The sensitivity of material properties to microscale surface structuring creates a design challenge that has precluded this technology development, however the availability of high-performance computing hardware combined with sophisticated optimization algorithms now permits the engineering of such materials. PC Krause and Associates, Inc. (PCKA) and The University of Texas (UT) will target two candidate applications with high potential for environmental and commercial impact: variable emissivity materials, and reduced emissivity glass. Both of these target applications offers independent paths to energy efficiency, along with clear routes to commercialization. Variable emissivity materials will directly reduce energy costs in diurnal climates. Likewise, the reduction of infrared emission from glass windows would address one of the costliest thermal losses in buildings of all sizes.

Benefits: Materials engineered for intelligent radiative behavior will directly affect the energy consumption required by large industrial facilities and campuses. The sustainability of NASA facilities will be improved by the installation of window glass and variable emissivity building materials developed as a result of the proposed work. The ability to design passive variable emissivity materials also has direct application in spacecraft thermal management, where thermal radiation can represent the only mode of heat transfer to and from the craft.

The target applications focus primarily on materials that will reduce HVAC requirements in homes and buildings. The U.S. Department of Energy estimates that approximately 70% of the electricity generated in the US is through fossil fuel combustion, which in turn accounts for approximately 40% of emissions of pollutants and greenhouse gases. The potential to reduce this reliance represents a large reduction in costs associated with heating and air conditioning, but also a reduction in environmental pollutants. Based on past success, it is estimated that this SBIR Program will result in annual licensable technology of value greater than $1M, and the addition of full-time staff at PCKA to support thermal management research.