Abstract: Spectrophotometer for the characterization of receivers of solar collectors in order to determine optical properties (transmittance and reflectance). The equipment allows the evaluation of a receiver tube in real time and in any kind of light conditions, both inside and outside. The equipment also allows the detection of the eccentricity between the outer tube and the inner tube, which directly influences the reliability of the measurement. The equipment has a mechanical system for allowing a rotation of the equipment around the tube in order to find the optimum measurement position and attach itself to the tube.

Abstract: A method is provided for producing a visual hydrogen sensor and to a sensor produced in this manner, the sensor allowing the presence of hydrogen gas in a medium to be detected by the naked eye as a result of a change of color in the sensor. The method involves the deposition of thin porous layers of oxides that do not absorb visible light in their completely oxidized state which become colored when they are partially reduced. This deposition is carried out using vapor phase deposition (PVD) in a glancing angle configuration (GLAD). The method also involves the preparation of a solution of an active metal precursor capable of dissociating the hydrogen molecule and a carrier vector and the deposition of this solution on the oxide layer in order to incorporate a minimum quantity of active metal within the pores of the oxide layer in the form of nanoparticles.

Abstract: Selective solar absorbent coating and manufacturing method, with solar absorption and low emissivity properties. The coating comprises a substrate (1) of metal, dielectric or ceramic material, at least one highly reflective metal layer (2) in mid-far infrared applied to the substrate itself which provides low emissivity properties, a mufti-layer structure of alternating dielectric and metallic layers (3) of subnanometric thickness applied to the reflective metal layer and at least one dielectric layer (4) that acts as an anti-reflective layer for the solar spectrum. The coating is applicable as a selective absorbent coating in absorbent tubes for parabolic-trough solar collectors, in solar panels for hot water, heating or domestic cooling, both in the form of absorbent tubes and absorbent sheets, in capture systems in tower solar thermoelectric power plants, and in capture systems in Stirling disk systems.

Abstract: Selective solar absorbent coating and manufacturing method, with solar absorption and low emissivity properties. The coating comprises a substrate (1) of metal, dielectric or ceramic material, at least one highly reflective metal layer (2) in mid-far infrared applied to the substrate itself which provides low emissivity properties, a multi-layer structure of alternating dielectric and metallic layers (3) of subnanometric thickness applied to the reflective metal layer and at least one dielectric layer (4) that acts as an anti-reflective layer for the solar spectrum. The coating is applicable as a selective absorbent coating in absorbent tubes for parabolic-trough solar collectors, in solar panels for hot water, heating or domestic cooling, both in the form of absorbent tubes and absorbent sheets, in capture systems in tower solar thermoelectric power plants, and in capture systems in Stirling disk systems.

Abstract: Spectrophotometer for the characterisation of receivers of solar collectors in order to determine optical properties (transmittance and reflectance). The equipment allows the evaluation of a receiver tube in real time and in any kind of light conditions, both inside and outside. The equipment also allows the detection of the eccentricity between the outer tube and the inner tube, which directly influences the reliability of the measurement. The equipment has a mechanical system for allowing a rotation of the equipment around the tube in order to find the optimum measurement position and attach itself to the tube.

Abstract: A method is provided for producing a visual hydrogen sensor and to a sensor produced in this manner, the sensor allowing the presence of hydrogen gas in a medium to be detected by the naked eye as a result of a change of colour in the sensor. The method involves the deposition of thin porous layers of oxides that do not absorb visible light in their completely oxidised state which become coloured when they are partially reduced. This deposition is carried out using vapour phase deposition (PVD) in a glancing angle configuration (GLAD). The method also involves the preparation of a solution of an active metal precursor capable of dissociating the hydrogen molecule and a carrier vector and the deposition of this solution on the oxide layer in order to incorporate a minimum quantity of active metal within the pores of the oxide layer in the form of nanoparticles.

Abstract: The invention relates to a spectrophotometer for the automated optical characterization of solar collector tubes and to a method for the operation thereof, that measures the coefficient of transmission of the glass tube and of reflection of the metal tube. The device includes all the necessary components for taking said measurement, such as the optical bench supporting the tube, the standard or framework, and the optical modules for the device, a main module that generates the light bundles, a measuring module that measures the coefficient of transmission of the outer glass tube and the coefficient of reflection of the inner metal tube, a mechanical system of tube rotation, an electronic system of data acquisition and processing, an external computer for controlling the device and processing the data measured, and a system of communication between the device and the computer.

Abstract: Selective solar absorbent coating and manufacturing method, with solar absorption and low emissivity properties. The coating comprises a substrate (1) of metal, dielectric or ceramic material, at least one highly reflective metal layer (2) in mid-far infrared applied to the substrate itself which provides low emissivity properties, a multi-layer structure of alternating dielectric and metallic layers (3) of subnanometric thickness applied to the reflective metal layer and at least one dielectric layer (4) that acts as an anti-reflective layer for the solar spectrum. The coating is applicable as a selective absorbent coating in absorbent tubes for parabolic-trough solar collectors, in solar panels for hot water, heating or domestic cooling, both in the form of absorbent tubes and absorbent sheets, in capture systems in tower solar thermoelectric power plants, and in capture systems in Stirling disk systems.

Abstract: System for supporting an evaporable getter, which can be installed in any type of solar power receiving tube and which is mounted using an automated method. The system consists of a clip-type supporting element having a substantially thin profile and an S-shaped base, the upper part thereof including a ring in which the pellet of evaporable getter is housed. The pellet is supported by the pins of the supporting element, dispensing with the need for an additional contact part in order to secure the pellet. The clip is secured to the bellows-type expansion compensator, such that it remains inside the vacuum zone of the solar power receiving tube.

Abstract: Insulating element for expansion compensation device and method for manufacture thereof, of the type used in solar energy collector absorber tubes, being formed by a single piece in the form of a ring and with a bellows-like end portion, which is filled with rock wool or other equivalent insulating material, so as to create a hot air chamber which minimizes heat losses.

Abstract: Device for connection between adjacent solar receiver tubes of the type which are at the end of the solar receiver tube (1) to be joined with another adjacent solar collector tube, comprising: An expansion compensating element with at least two concentric bellows (7, 8) that are connected to each other and to a rigid ring (9) by means of a welded joint, which keeps them concentric in the expansion and compression process and joined to the glass tube (4) by the cover (12) and glass-metal transition element (21), A connection flange (5) to connect the solar receiver tube (1) to the one adjacent thereto, the flange (5) being a round metal plate with a hole that houses the absorber tube (3), Some through bolts (20) passing through the connection flange (5) to attach it with flange of the adjacent receiving tube (1).

Abstract: Selective solar absorbent coating and manufacturing method, with solar absorption and low emissivity properties. The coating comprises a substrate (1) of metal, dielectric or ceramic material, at least one highly reflective metal layer (2) in mid-far infrared applied to the substrate itself which provides low emissivity properties, a mufti-layer structure of alternating dielectric and metallic layers (3) of subnanometric thickness applied to the reflective metal layer and at least one dielectric layer (4) that acts as an anti-reflective layer for the solar spectrum. The coating is applicable as a selective absorbent coating in absorbent tubes for parabolic-trough solar collectors, in solar panels for hot water, heating or domestic cooling, both in the form of absorbent tubes and absorbent sheets, in capture systems in tower solar thermoelectric power plants, and in capture systems in Stirling disk systems.

Abstract: The invention relates to a method for producing a solar power receiving tube and to the resulting tube, which is of the type that includes: an outer glass tube, an inner metal absorber through which a heat-transfer fluid flows, and an intermediate area in which the vacuum is produced. The method comprises the following steps: i. Production of the metal tubes ii. Production of the glass tubes: namely a longer central glass tube and two shorter glass tubes for the ends. iii. Process for the production of the Kovar rings or glass-metal transition elements iv. Process for the welding of the Kovar rings to the tubes v. Process for the production of the bellows or expansion compensating devices assemblies vi. Assembly of the products obtained in the preceding operations vii. Creation of the vacuum and anodising of the welds.

Abstract: Portable spectrophotometer and method for characterizing solar collector tubes for simultaneously and on-field characterizing reflection and transmission coefficients. This device includes all the components needed to take this measurement, such as a module that takes the measurement of the reflection coefficient (R) of the inner tube (1?), a module that takes the measurement of transmission coefficient (T) of the outer tube (1?), an electronic data acquisition and processing system (12), an external computer (13) for controlling the device and sending the measured data (17) and a communication system (15) between device and the computer (13).

Abstract: Superheated steam tower receiver with a well-defined configuration that benefits the transfer of heat between the surface of the component and the working fluid. Composed of at least four subpanels that define the circulation circuit for the steam by means of internal passages. The component is provided with saturated steam and for the production of said steam it is possible to use other solar concentrator technology. The proposed configuration minimizes the technological risks inherent in superheated steam receiver technology where drawbacks arise in the structure of the material owing to the thermal cycles to which the solar component is subjected.

Abstract: The invention relates to a method for in situ coating a tower solar receiver in order to protect the surface of the receiver from corrosion and to increase absorptivity of same, which is carried out in several steps: surface preparation, application of the coating, curing, optional vitrification, and controlled cooling. The surface preparation is done by zones depending on the size of the receiver, a methodology that enables an intercalated application of the coating in order to minimize the risk of corrosion. The curing stage is carried out by supplying steam to the inside of the receiver tubes, and temperature requirements above the operating limits of the boiler are adjusted with the solar field as support system. Vitrification is done using saturated steam traveling through the receiver tubes and concentrating solar radiation on the surface of the receiver from the solar field.

Abstract: New expansion compensating device and manufacturing method of the same, of those used in solar power absorber tubes featuring a dual bellows design where the height of the waves of the bellows is not regular, but the second wave is greater (where it supports more load) and diminishes towards the ends. With this design improving the performance of the receiver is achieved because it shortens the length of the device and consequently there is more surface area receiving solar radiation as well as it decreases the necessary diameter of glass tube and therefore its cost.

Abstract: The invention relates to a novel arrangement of non-evaporable getters for a tube solar collector, said tube collector being of the type that includes an outer glass tube (2); an inner metal tube (3) through which a heat-transfer fluid flows; a vacuum chamber between both tubes; and, at the ends, non-evaporable getter pellets (1) that absorb gas molecules that could produce a loss of vacuum between the inner tube (3) and the outer tube (2) and the covers (8) at which a bellows-type expansion compensating device (4) is positioned. The inner metal tube (3) and outer glass tube (2) are positioned eccentrically to one another, forming a thicker area and a narrower area in the cover (8), said narrower area being used for the positioning, by means of bonding, of the non-evaporable getter pellets (1).

Abstract: Portable spectrophotometer and method for characterizing solar collector tubes for simultaneously and on-field characterizing reflection and transmission coefficients. This device includes all the components needed to take this measurement, such as a module that takes the measurement of the reflection coefficient (R) of the inner tube (1?), a module that takes the measurement of transmission coefficient (T) of the outer tube (1?), an electronic data acquisition and processing system (12), an external computer (13) for controlling the device and sending the measured data (17) and a communication system (15) between device and the computer (13).

Abstract: Novel glass compositions and method for producing a glass/metal join, in which the novel glass comprises: Oxide (%) B2O3 ??8-13.5 Al2O3 5-9 Na2O 3-9 K2O 0-5 CaO 2-4 MgO 0-4 ZnO 0-4 SiO2 Up to 100 depending on the necessary requirements, owing to the significance thereof the thermal expansion coefficient, such that this thermal expansion coefficient is adjusted to match that of the metal part or alloy with which the glass/metal weld is to be achieved, which makes it possible to satisfactorily produce said weld which results in a strong glass/metal join, that is free from tensile stresses and that is durable over time and may be used, inter alia, to obtain parts that form part of solar collectors.