Abstract: A method includes operating the refrigeration system in a cooling mode wherein a space is conditioned, and also includes transferring heat from a heat-transfer circuit to a thermoelectric device to a refrigeration circuit. A method further includes operating the refrigeration system in a defrost mode of operation including transferring heat through the thermoelectric device to the heat-transfer circuit to a heat exchanger.

Abstract: A refrigeration system for multi-temperature and single-temperature applications combines a refrigeration circuit and a single-phase fluid heat-transfer circuit in heat-conducting contact through a thermoelectric device. A vapor compression cycle provides a first stage of cooling and the thermoelectric device in conjunction with the heat-transfer circuit provides the second stage of cooling. Polarity of the thermoelectric device can be reversed to provide a defrost function for the refrigeration system.

Abstract: A method of conditioning a space with a refrigeration system includes circulating a first heat sink for a first side of a thermoelectric device and circulating a second heat sink for a second side of the thermoelectric device. The method also includes transferring heat between the first heat sink and the second heat sink to condition the space.