Design of thermoelectric heat pump unit for active building envelope systems

Active building envelope (ABE) systems represent a new thermal control technology that actively uses solar energy to compensate for passive heat losses or gains in building envelopes or other enclosures. This paper introduces initial steps in exposing the community to this new technology, and explores an optimization based design strategy for its feasible application. We discuss the overall ABE system, and focus on the design and analysis of a key component—the thermoelectric heat pump unit, or the TE unit. This unit becomes an integral part of the generic enclosure, and is a collection of thermoelectric coolers, or heaters. As a critical component of the optimization based design strategy, computationally inexpensive approximate analytical models of generic TE coolers/heaters (referred to as TE coolers) are developed. A multi-objective optimization technique is implemented to design and evaluate different design configurations of the TE unit. The multi-objective optimization simultaneously minimizes two design objectives: (1) the total input power required to operate the TE unit and (2) the number of TE coolers for economic considerations. Preliminary results indicate that the total input power required to operate the TE unit decreases as the distribution density of the TE coolers increases. In addition, the thermal resistance of the heat sink (attached to the TE cooler) plays a key role in determining the number of TE coolers required. These preliminary findings may have practical implications, influencing the implementation of the ABE system.