A foldable parabolic solar collector includes a first panel having a semi-parabolic reflective inner surface, a central tube to which the first panel is fixed, and a second panel having a semi-parabolic reflective inner surface. The second panel is pivotably mounted to the central tube with the reflective inner surface of the second panel facing the reflective inner surface of the first panel. A receiver tube carries a heat transfer fluid. A tracking motor rotates the central tube. A torque sensor lies in between the tracking motor and the central tube and is configured to measure torque between the tracking motor and the central tube. A servomotor pivots the second panel about the central tube between an open position and a closed position when it is determined by a controller that the torque between the tracking motor and the central tube exceeds a predetermined torque threshold.

Single- or multilayered coating, such as a selective solar absorber coating or a coating being part of an integrated electronic circuit, comprising one or more layers containing germanium (Ge) doped VO.sub.2+x, where 0.1x0.1.

Single- or multilayered coating, such as a selective solar absorber coating or a coating being part of an integrated electronic circuit, comprising one or more layers containing germanium (Ge) doped VO.sub.2+x, where 0.1x0.1.

Methods of arranging and operating a molten salt solar thermal energy system are disclosed. Molten salt flows from a set of cold storage tanks to solar receivers which heat the molten salt to a maximum temperature of about 850 F. The heated molten salt is sent to a set of hot storage tanks. The heated molten salt is then pumped to a steam generation system to produce steam for process and/or power generation. Lower salt temperatures are useful in processes that use lower steam temperatures, such as thermal desalination. Lower salt temperatures and low chloride molten salt reduce the corrosion potential, permitting the use of lower cost alloys for the solar receivers, hot storage tanks, salt pumps, piping and instrumentation and steam generation system. Multiple sets of modular, shop assembled storage tanks are also used to reduce the amount of salt piping, simplify draining, and reduce field assembly and plant cost.

Methods of arranging and operating a molten salt solar thermal energy system are disclosed. Molten salt flows from a set of cold storage tanks to solar receivers which heat the molten salt to a maximum temperature of about 850 F. The heated molten salt is sent to a set of hot storage tanks. The heated molten salt is then pumped to a steam generation system to produce steam for process and/or power generation. Lower salt temperatures are useful in processes that use lower steam temperatures, such as thermal desalination. Lower salt temperatures and low chloride molten salt reduce the corrosion potential, permitting the use of lower cost alloys for the solar receivers, hot storage tanks, salt pumps, piping and instrumentation and steam generation system. Multiple sets of modular, shop assembled storage tanks are also used to reduce the amount of salt piping, simplify draining, and reduce field assembly and plant cost.

Disclosed herein is a solar thermal collector system that is particularly configured for dual use as a radiant cooling system. In accordance with aspects of a particular embodiment of the invention, the solar thermal collector system includes a solar thermal module having a glazing sheet at a top, exterior surface, and an absorber sheet within the module positioned below and spaced apart from the glazing sheet. The absorber sheet and the glazing sheet are fluidly connected to a fluid handling system, and are configured to carry a working fluid that may be heated in the absorber sheet by the sun to transfer such heat to equipment within the facility in which the system is installed, and to carry the working fluid through the glazing sheet to transfer heat collected from the facility to space. The solar thermal collector module is preferably provided a thermally actuated valve that allows the working fluid to also flow through the glazing sheet, which results in self-regulation of the temperature of the module below a critical design temperature.

The present invention relates to a heat exchanger comprising a plurality of exchange tubes (1) mounted joined longitudinally in such a way as to create a front surface portion (4) creating an obstacle to an incident heat flow and at least one heat flow sensor (5) disposed in a support (12) located between two adjacent exchange tubes (1), characterized in that the support (12) of the heat flow sensor (5) is brazed to at least one of the two tubes (1) and is flattened on the side that is to be disposed at the front (4), with reference to the incident heat flow, in such a way as to be able to be inserted between the two adjacent tubes (1) at the location of said local deformations (11).

A heat transfer device having a working fluid capable of circulating around a fluid flow path, the circulation around the fluid flow path bringing the working fluid in and out of thermal contact with a heat source, the heat transfer device comprising: a fluid containing portion internally defining a working fluid flow path; a heat source at least partially in thermal contact with the fluid containing portion; a gas substance generator at least partially within the fluid containing portion, and arranged to generate bubbles of vapor capable of driving the working fluid along a portion of the working fluid flow path in thermal contact with the heat source; wherein, in use, the driven working fluid absorbs heat from the heat source and transports the heat away from the heat source; and the driven working fluid returns to the gas substance generator to be recycled about the fluid flow path.

A solar power plant for generating steam is comprised of a spherical shell, the interior of which is sealed from the outside atmosphere and which is mounted adjacent the top of a vertical tower. A plurality of heliostats surrounds the tower and the direct sunrays onto the sphere for heating the same sphere. A spray nozzle within the sphere directs water supplied to it from an external source onto the interior surface of the sphere to create steam. The steam is withdrawn and directed to a turbine or the like for generating electricity. A motor rotates the sphere about its vertical axis thereby regularly exposing a different portion of the sphere to the heliostats to prevent the sphere from melting.

A foldable parabolic solar collector includes a first panel having a semi-parabolic reflective inner surface, a central tube to which the first panel is fixed, and a second panel having a semi-parabolic reflective inner surface. The second panel is pivotably mounted to the central tube with the reflective inner surface of the second panel facing the reflective inner surface of the first panel. A receiver tube carries a heat transfer fluid. A tracking motor rotates the central tube. A torque sensor lies in between the tracking motor and the central tube and is configured to measure torque between the tracking motor and the central tube. A servomotor pivots the second panel about the central tube between an open position and a closed position when it is determined by a controller that the torque between the tracking motor and the central tube exceeds a predetermined torque threshold.