Comfort units and systems, methods, and devices for use thereof

An environmental control system comprising:

• a comfort unit constructed to create a thermal microenvironment around one or more users, the thermal microenvironment having a temperature different from that of an environment surrounding the microenvironment, the comfort unit comprising:
• a thermal regulation module that cools air for the thermal microenvironment;
• an air delivery module that directs the cooled air to the one or more users to create the thermal microenvironment;
• and
• a first control module that controls the thermal regulation module and the air delivery module according to at least first and second modes of operation,
• wherein the thermal regulation module includes a heat pump system and a thermal storage material (TSM),
• wherein the heat pump system includes a first heat exchanger, a second heat exchanger, a compressor, and an expansion valve connected together by a working fluid loop,
• wherein the TSM is constructed to store heat therein and is thermally coupled to the first heat exchanger,
• wherein the air delivery module is thermally coupled to the second heat exchanger, and
• wherein the first control module controls the thermal regulation module and the air delivery module such that:
• in the first mode of operation to cool the air for the thermal microenvironment, the heat pump system is configured as a vapor compression system (VCS) with the first heat exchanger acting as a condenser of the VCS, the VCS stores waste heat from the condenser in the TSM, and the TSM changes temperature and/or phase to store the waste heat therein, and
• in the second mode of operation to recharge the TSM, the heat pump system is configured as a thermosiphon such that heat stored in the TSM is released via the first heat exchanger and working fluid in the working fluid loop is passively driven by a density difference due to a temperature differential between the TSM and the environment.