Passive radiative cooling structures and apparatus manufactured with such cooling structures conserve energy needs. A flexible film transparent to visible light incorporates particles at a volume percentage larger than 25% so as to absorb and emit infrared radiation at wavelengths where Earth's atmosphere is transparent. Another film transparent to visible light is thin and flexible and configured to absorb and emit infrared radiation at wavelengths where Earth's atmosphere is transparent, wherein etchings or depositions are present on one or both surfaces. A high efficiency cooling structure has an emissive layer sandwiched between a waveguide layer and a thermal conductive layer. A solar cell panel is covered by a transparent passive radiative cooling film. A container housing an active cooling unit incorporates passive radiative cooling structures on one or more exterior surfaces.

A heat exchange conduit includes a body having a first portion including a first flow channel and a second portion including a second flow channel. A cross-section of the heat exchange conduit varies over a length of the heat exchange conduit.

A method for improving heat transfer during distillation and concentration of extract with solvent includes providing a distillation vessel having a heat transfer surface and preparing the heat transfer surface with a plurality of surface features. A distillation and concentration system includes a distillation vessel having a heat transfer surface prepared with a plurality of surface features in accordance with the method.

A heat exchanger coating composition includes an aqueous dispersion having a water-repellent resin containing spherical particles with an average particle size of 2 μm or more and 50 μm or less.

A heat exchanger coating composition includes an aqueous dispersion having a water-repellent resin containing spherical particles with an average particle size of 2 μm or more and 50 μm or less.

A heat storage device including a metal layer containing a protrusion-and-recess-shaped object, in which the protrusion-and-recess-shaped object has an average height of 100 nm or more and 1,000 nm or less.

An induction cooking appliance apparatus includes an induction coil, and a coil carrier configured to hold the induction coil and including a heat dissipation unit for dissipating heat emitted by the induction coil.

An induction cooking appliance apparatus includes an induction coil, and a coil carrier configured to hold the induction coil and including a heat dissipation unit for dissipating heat emitted by the induction coil.

The present invention relates to a technique of cooling a temperature on the surface or under a material by emitting heat under a radiative cooling device to the outside while minimizing the absorption of light in a solar spectrum by forming a paint coating layer with excellent radiative cooling performance on various surfaces. A radiative cooling device according to an embodiment of the present invention may include a paint coating layer formed by coating or dyeing on various surfaces a paint solution mixed with nano or microparticles of which a particle size and a composition are determined in consideration of infrared emissivity and reflectance to incident sunlight in a wavelength range corresponding to a sky window and a binder mechanically connecting the surfaces of the nano or microparticles in a solvent.

A dual-mode heating and cooling system includes a dual-mode heating and cooling device including a cooling part and a heating part that are configured to be selectively exposed to sunlight in a cooling mode and a heating mode, respectively, with the cooling part configured to provide radiative cooling to a structure, and with the heating part configured to provide solar heating to the structure.