A method of manufacturing a solar heat collection pipe includes an inner circumferential film forming step of forming an antireflection film on an inner surface of a glass pipe and an outer circumferential film forming step of forming an antireflection film on an outer surface of the glass pipe. These film forming steps are performed so that a part of a coating film through which a coating material is flowed when the coating material is discharged from the glass pipe in a coating material discharging step of the inner circumferential film forming step and a part of a coating film with which the coating material is in contact when the glass pipe is lifted from the coating material in a lifting step of the outer circumferential film forming step are positioned within a half circumference of the glass pipe in a circumferential direction of the glass pipe.

Provided is a solar collector that captures and utilizes solar energy and includes a plurality of vacuum tubes which are disposed by extending horizontally and are disposed parallel to each other with a predetermined distance; and a reflection plate having a substantially planar shape, which reflects solar light on an opposite side of the sun with respect to the plurality of vacuum tubes, in which the reflection plate includes a reflection surface having a serrated section at a corresponding position between vacuum tubes adjacent to each other, and in the reflection surface, one face of a serration forms a first reflection surface that reflects the solar light to the vacuum tube on a lower side among the vacuum tubes adjacent to each other.

Provided is a solar collector that captures and utilizes solar energy and includes a plurality of vacuum tubes which are disposed by extending horizontally and are disposed parallel to each other with a predetermined distance; and a reflection plate having a substantially planar shape, which reflects solar light on an opposite side of the sun with respect to the plurality of vacuum tubes, in which the reflection plate includes a reflection surface having a serrated section at a corresponding position between vacuum tubes adjacent to each other, and in the reflection surface, one face of a serration forms a first reflection surface that reflects the solar light to the vacuum tube on a lower side among the vacuum tubes adjacent to each other.

Systems and methods for radiative cooling and heating are provided. For example, systems for radiative cooling can include a top layer including one or more polymers, where the top layer has high emissivity in at least a portion of the thermal spectrum and an electromagnetic extinction coefficient of approximately zero, absorptivity of approximately zero, and high transmittance in at least a portion of the solar spectrum, and further include a reflective layer including one or more metals, where the reflective layer has high reflectivity in at least a portion of the solar spectrum.

Systems and methods for radiative cooling and heating are provided. For example, systems for radiative cooling can include a top layer including one or more polymers, where the top layer has high emissivity in at least a portion of the thermal spectrum and an electromagnetic extinction coefficient of approximately zero, absorptivity of approximately zero, and high transmittance in at least a portion of the solar spectrum, and further include a reflective layer including one or more metals, where the reflective layer has high reflectivity in at least a portion of the solar spectrum.

A solar absorber body for a concentrating solar power system, said solar absorber body including: a tube, designed to contain a heat transfer medium and including a first part designed to be exposed to the sunlight and a second part designed to be unexposed to the sunlight, an assembly of fins made of thermally conductive material, and a selective coating arranged at least on the outer surface of the first part of the tube, said assembly of fins defining at least two longitudinal passages inside the tube, said passages being adjacent in a sectional plane perpendicular to the longitudinal axis of the tube, said assembly of fins being configured to create a continuous thermal bridge inside the tube from at least a portion of the inner surface of first part of the tube to at least a portion of the inner surface of the second part of the tube.

Systems and methods disclosed herein are directed towards the fabrication of a solar absorber comprising an IR reflector layer deposited on a substrate; a first cermet layer deposited in contact with the IR reflector layer; a second cermet layer deposited in contact with the first cermet layer; a first anti-reflection coating layer deposited in contact with the second cermet layer; a second anti-reflection coating layer deposited in contact with the first anti-reflection coating layer. A sputtering process may be used to deposit some or all of the layers, and the YSZ layers in each cermet layer may be deposited with a tuned partial oxygen pressure in order to form a layer that is oxygen-deficient.

Systems and methods disclosed herein are directed towards the fabrication of a solar absorber comprising an IR reflector layer deposited on a substrate; a first cermet layer deposited in contact with the IR reflector layer; a second cermet layer deposited in contact with the first cermet layer; a first anti-reflection coating layer deposited in contact with the second cermet layer; a second anti-reflection coating layer deposited in contact with the first anti-reflection coating layer. A sputtering process may be used to deposit some or all of the layers, and the YSZ layers in each cermet layer may be deposited with a tuned partial oxygen pressure in order to form a layer that is oxygen-deficient.

A solar heat collection tube with improved optical transmittance and durability to the external environment includes an inner tube through the interior of which a heat medium can flow, an outer tube that covers an outer periphery of the inner tube such that an annular heat insulating space is formed between the outer tube and the inner tube, and thermal expansion difference absorbing means or absorbing a thermal expansion difference between the inner tube and the outer tube. The outer tube is a glass tube, a first anti-reflection film is formed on an inner surface of the glass tube, a second anti-reflection film is formed on an outer surface of the glass tube, the second anti-reflection film is more durable to the external environment than the first anti-reflection film, and the first anti-reflection film has a higher optical transmittance than the second anti-reflection film.

A solar heat collection tube with improved optical transmittance and durability to the external environment includes an inner tube through the interior of which a heat medium can flow, an outer tube that covers an outer periphery of the inner tube such that an annular heat insulating space is formed between the outer tube and the inner tube, and thermal expansion difference absorbing means or absorbing a thermal expansion difference between the inner tube and the outer tube. The outer tube is a glass tube, a first anti-reflection film is formed on an inner surface of the glass tube, a second anti-reflection film is formed on an outer surface of the glass tube, the second anti-reflection film is more durable to the external environment than the first anti-reflection film, and the first anti-reflection film has a higher optical transmittance than the second anti-reflection film.