Prospect of thermoelectric air conditioner for building application and their building integration methods

The refrigerants used in conventional vapour-compression air conditioning systems have detrimental effects on the global environment. Phasing-down hydrofluorocarbon (HFC) refrigerants for HVAC equipment over the next 20 years has been proposed and the refrigerants are undergoing a massive shift globally. In this aspect, the thermoelectric technology has attracted considerable attentions as its ability to directly convert between thermal and electrical energy using a simple solid-state semiconductor device, offering sustainable solution in various fields. This paper presents a prospect of the thermoelectric air conditioning technology for building applications. Recent advances in thermoelectric materials, thermoelectric module and thermoelectric heating/cooling system design, which would provide the potential to greatly improve the COP of the thermoelectric air conditioner, are reviewed. Utilising the waste heat of the thermoelectric system for domestic applications and for improving the overall COP of the system is discussed. It is prospected that the thermoelectric air conditioner would be competitive or superior to the conventional ones regarding to its energy efficiency with the development of the thermoelectric technologies. In addition, the thermoelectric systems have the advantages of be a very compact flat unit and are easy to be integrated into the building structure. The paper also proposes a novel multifunctional thermoelectric building energy façade system that integrates a thermoelectric heat pump unit into a double-skin façade to provide heating and cooling, heat recovery ventilation and domestic hot water or drying services for buildings, based on the waste heat utilisation. Except for integration into façade, several additional building integration methods of the system are also proposed and shown schematically.