The invention relates to a field of open-flow solar collectors, and specifically to flat solar collectors with wetting the underneath sides of their solar radiation absorbing plates with liquid heat transfer medium. More specifically, the invention proposes the flat solar collector, which operates with relatively low flow rate of the heat transfer medium on the underneath side of the solar radiation absorbing plate, with flow in form of some rivulets. The invention describes some technical solutions, which restrict meandering rivulets' flow. The proposed flat solar collector can be applied for heating water or other liquids and for evaporation and concentration of aqueous solutions.

A heat receiver, a reactor, and a heater utilize the heat of concentrated solar light for thermal decomposition and/or chemical reaction of coals, etc. The heat receiver includes: a side portion forming a substantially cylindrical side surface; a substantially circular bottom portion connected to the lower edge of the side portion; and a ceiling connected to the upper edge of the side portion. A substantially circular aperture is formed in the center of the ceiling. The heat receiver has a substantially cylindrical cavity and the opening portion is open. When the cavity has a diameter of D and a length of L, and the aperture has a diameter of d, d=D/2 or less and L=2D or more. Concentrated solar light entering the heat receiver is to be contained in the heat receiver to effectively utilize the solar light.

The invention includes a parabolic solar concentrator typified by a highly integrated structure whereby, mirror, aerodynamic elements, a shell structure, cooling elements and other elements have been integrated to form a unibody structure, which is both stiffer and lighter than traditional trough structures. The invention includes; aerodynamic features that greatly limit lift forces induced by high speed winds, a receiver with liquid cooling for better control of PV cell temperatures and which allows for the collection of the heat for beneficial use, accommodations for a solar tracker, and improvements in the focusing and distribution of light using secondary mirrors. The receiver incorporates specific details to improve heat transfer and reduce parasitic pumping loads and incorporates secondary mirrors to increase light acceptance angles. Automated mirror washing is addressed. In applications where the heat is un-utilized the integrated radiator is employed to dissipate the heat using both convection and radiation heat transfer.

A solar water heater absorber absorbs the sun's energy on the surface of a twin-walled polycarbonate panel and conducts the heat from the sun through the panel wall into fluid flow through channels of the panel. The panel is an extruded polycarbonate glazing material that consists of two panes connected by longitudinal ribs to form a plurality of water channels that may further include twisted strips providing a helical water flow pattern that increases turbulence within the water channels. The panel is connected to large pipes or headers on the top and bottom ends of the panel that receive the heated fluid from the water channels, allow the heated fluid to exit the panel, and for return water to re-enter the panel in a solar water heating system.

A particle suppressor can be used in a particle receiver to reduce the particle loss rate. The receiver can include a rotating drum with an inliner. The particle suppressor can include a retaining surface. The retaining surface can be spaced away from and extend concentrically with the inline. A spacing gap between the inliner and the retaining surface can dampen the motion of bouncing particles. The spacing gap can be between 15 mm and 20 mm. In some embodiments, the particle suppressor can include a support ring with a plurality of suppressor segments disposed circumferentially around the support ring. The particle suppressor can include a plurality of suppressor segments coupled directly to the inliner. A heat shield can be coupled to the particle suppressor. A support bracket can suspend the particle suppressor within the receiver.

A heat exchanger assembly includes a first stage heat exchange section defining one or more intakes for receiving a fluid. The first stage heat exchange section includes one or more preheater elements defining one or more preheat flowpaths extending radially inward from the one or more intakes with respect to a centrally disposed axis of the heat exchanger assembly. The one or more preheater elements include one or more guide vanes configured to guide a flow of the fluid in a spiral path from the one or more intakes toward the centrally disposed axis. A centrally disposed second stage heat exchange section is fluidly connected to the one or more preheat flowpaths to receive the fluid from the one or more preheat flowpaths.

A heat exchanger assembly includes a first stage heat exchange section defining one or more intakes for receiving a fluid. The first stage heat exchange section includes one or more preheater elements radially insertable into the first stage heat exchange section with respect to a centrally disposed axis of the heat exchanger assembly. The preheater elements define one or more preheat flowpaths extending radially inward from the intakes. The preheater elements transfer thermal energy to or from the fluid as the fluid flows from the intakes through the preheat flowpaths. A centrally disposed second stage heat exchange section defines an axial flowpath that is fluidly connected to the preheat flowpaths to receive the fluid from the preheat flowpaths. The second stage heat exchange section transfers thermal energy to or from the fluid as the fluid flows through the axial flowpath.

A heat exchanger assembly includes an absorber element defining an axial flowpath for a fluid extending along an axis. The absorber element includes an outer support wall and one or more support members extending radially inward from the outer support wall with respect to the axis. The heat exchanger assembly also includes one or more heat exchange elements floatably coupled to the one or more support members where the one or more heat exchange elements extend along the axial flowpath.

A heat collector includes a body including a hollow portion extending from a first end to a second end of the body and being a metal-extruded body having a light-receiving surface to receive sunlight, a pair of lids adjacent to the first end and the second end and covering the hollow portion, an inlet located in one of the pair of lids to allow a heating medium to enter the hollow portion, and an outlet located in one of the pair of lids to allow the heating medium to exit the hollow portion.

The element on which solar radiation is concentrated, specifically, a vacuum tube, remain static at all times with respect to the movements that a parabolic reflective surface may make according to the direction of solar radiation, such that inlet and outlet pipes of the vacuum tube do not need to be articulated, which facilitates the installation and insulation thereof and reduces production costs. The parabolic reflective surface can pivot 360 with respect to the vacuum tube without interfering with the pipes, allowing an active safety system for protecting against strong winds and preventing overheating to be produced, in addition to allowing the surfaces to be cleaned by means of nozzles spray pressurized water. The collector also includes passive safety means against strong winds.