Thermoelectric Materials in Exterior Walls: Experimental Study on Using Smart Facades for Heating and Cooling in High-Performance Buildings

This article discusses design, prototype development and an experimental study of facade-integrated thermoelectric (TE) materials. TEs are smart materials that have the ability to produce a temperature gradient w hen electricity is applied, exploiting the Peltier effect, or to generate a voltage w hen exposed to a temperature gradient, utilizing the Seebeck effect. TEs can be used for heating, cooling, or pow er generation. In this research, heating and cooling potentials of these novel systems w ere explored. Initially, tw o low fidelity prototypes w ere designed and constructed, w here one prototype w as used to study integration of TE modules (TEM) as stand-alone elements in the facade, and one prototype w as used to explore integration of TEMs and heat sinks in facade assemblies. Both prototypes w ere tested, in ambient conditions and w ithin a thermal chamber. The thermal chamber w as used to represent four different exterior environmental conditions (0°F, 30°F, 60°F and 90°F), w hile the interior conditions w ere kept constant at room temperature. The supplied voltage to facade-integrated TEMs varied from 1 to 8 V. Temperature outputs of TEMs for all investigated thermal conditions w ere measured using thermal imaging, w hich are discussed in detail in this article. The results indicate that w hile stand-alone facade-integrated TEMs are not stable, addition of heat sinks improves their performance drastically. Facade-integrated TEMs w ith heatsinks show ed that they w ould operate w ell in heating and cooling modes under varying exterior environmental conditions.