A refrigeration device, comprising: a thermal transfer unit including a set of hollow tubes forming an evaporative region, a set of hollow tubes forming a condensing region, and one or more hollow tubes forming an adiabatic region connecting the evaporative region and the condensing region, wherein the hollow tubes are sealed to each other to form a contiguous interior region; one or more reversible valves operably attached to the one or more hollow tubes forming the adiabatic region; a container with one or more walls sealed to hold a quantity of phase change material, PCM, the container comprising a set of refrigeration coils, the one or more walls including an aperture sealed around the set of refrigeration coils and wherein the condensing region of the thermal transfer unit is in thermal contact with the one or more walls; a refrigeration compressor unit including the set of refrigeration coils, wherein the set of refrigeration coils traverse the one or more walls of the container; one or more walls forming a storage region, wherein the evaporative region of the thermal transfer unit is in thermal contact with the one or more walls forming the storage region; a controller operably connected to the one or more reversible valves and the refrigeration compressor unit; characterised by further comprising: a reservoir for refrigeration fluid positioned at a low position within the evaporative region of the thermal transfer unit; a thermal conduit positioned between the reservoir and an exterior region of the refrigeration device; and a reversible valve operably connected to the thermal conduit, the reversible valve operably connected to the controller. a thermal transfer unit including a set of hollow tubes forming an evaporative region, a set of hollow tubes forming a condensing region, and one or more hollow tubes forming an adiabatic region connecting the evaporative region and the condensing region, wherein the hollow tubes are sealed to each other to form a contiguous interior region; one or more reversible valves operably attached to the one or more hollow tubes forming the adiabatic region; a container with one or more walls sealed to hold a quantity of phase change material, PCM, the container comprising a set of refrigeration coils, the one or more walls including an aperture sealed around the set of refrigeration coils and wherein the condensing region of the thermal transfer unit is in thermal contact with the one or more walls; a refrigeration compressor unit including the set of refrigeration coils, wherein the set of refrigeration coils traverse the one or more walls of the container; one or more walls forming a storage region, wherein the evaporative region of the thermal transfer unit is in thermal contact with the one or more walls forming the storage region; a controller operably connected to the one or more reversible valves and the refrigeration compressor unit; characterised by further comprising: a reservoir for refrigeration fluid positioned at a low position within the evaporative region of the thermal transfer unit; a thermal conduit positioned between the reservoir and an exterior region of the refrigeration device; and a reversible valve operably connected to the thermal conduit, the reversible valve operably connected to the controller. a reservoir for refrigeration fluid positioned at a low position within the evaporative region of the thermal transfer unit; a thermal conduit positioned between the reservoir and an exterior region of the refrigeration device; and a reversible valve operably connected to the thermal conduit, the reversible valve operably connected to the controller.