A heat management system includes a tank and a thermal siphon attached to the tank. The thermal siphon contains a liquid that absorbs heat via thermal conduction from the tank. The liquid is heated to a vaporization point, and the heat from the vaporized liquid is transferred to cooling fins extending from the thermal siphon.

A heat management system includes a tank and a thermal siphon attached to the tank. The thermal siphon contains a liquid that absorbs heat via thermal conduction from the tank. The liquid is heated to a vaporization point, and the heat from the vaporized liquid is transferred to cooling fins extending from the thermal siphon.

An integrated type air conditioning device includes a first refrigeration cycle that is an evaporative cooling type, a second refrigeration cycle that is a vapor-compression type, a blower device, and a housing accommodating the first and second cycles. The first refrigeration cycle includes an evaporation heat exchanger, a condensation heat exchanger, and a first refrigerant pipe. The second refrigeration cycle includes a compressor, a condenser, a decompression device, an evaporator, and a second refrigerant pipe. The housing is partitioned into an interior air passage and an exterior air passage. The evaporation heat exchanger and the evaporator are positioned in the interior air passage, the evaporation heat exchanger being located upstream of the evaporator with respect to an interior airflow in the interior air passage. The blower device is disposed in the interior air passage and is driven to generate the interior airflow in the interior air passage.

A heat dissipation device includes: a first plate with a first surface on which a first heat dissipation fin is formed; a second plate with a first surface on which a second heat dissipation fin is formed, and a heat conduction unit that passes through a first through-hole of the first plate and a second through-hole of the second plate.