Stanford University

Heating, Ventilation, and Air Conditioning (HVAC) account for 13% of energy consumed in the U.S. and about 40% of the energy used in a typical U.S. residence, making it the largest energy expense for most homes. Even though more energy-efficient HVAC technologies are being adopted in both the commercial and residential sectors, these technologies focus on efficiently heating or cooling large areas and dealing with how the building’s net occupancy changes during a day, a week and across seasons. Building operators have to tightly manage temperature for an average occupancy comfort level; but the occupants only occupy a small fraction of the building’s interior. There is a critical need for technologies that create localization of thermal management to relax the temperature settings in buildings, reduce the load on HVAC systems and enhance occupant comfort. This is achieved by tailoring the thermal environment around the individual, thus saving energy by not over-heating or over-cooling areas within the building where the occupants do not reside.

Stanford University will develop transformative methods for integrating photonic, or radiant energy structures into textiles. Controlling the thermal photonic properties of textiles can significantly influence the heat dissipation rate of the human body, which loses a significant amount of heat through thermal radiation. To achieve heating, the team utilizes metallic nanowire embedded in textiles to enhance reflection of body heat. To achieve cooling, the team utilizes visibly opaque yet infrared transmissivity (IR) transparent textile. These techniques for heating and cooling have not yet been achieved to date. The team will leverage advances in photonic structures to build textiles with varying amounts of infrared transparency and reflectivity to enable a wearer to achieve comfort in a wider temperature range, and therefore generate a substantial reduction of energy consumption for both heating and cooling.

If successful, DELTA technology could increase energy efficiency, reduce emissions produced by powering traditional HVAC systems, and enable more sustainable heating and cooling architectures for energy-efficient building design.