WO2016115610A1

WO2016115610A1 - Reflector system and a convex mirror method for solar and pv systems

Info

Publication number: WO2016115610A1
Application number: PCT/BG2016/000002
Authority: WO
Inventors: Gancho MITEV
Original assignee: Mitev Gancho
Priority date: 2015-01-21
Filing date: 2016-01-21
Publication date: 2016-07-28

Abstract

The invention relates to the field of "Batteries: thermoelectric and photovoltaic with concentrators, orientators, reflectors". It turns out to be a combination of existing up-to-date components. The Reflector system invented is not a concentrator. It comprises one or more diffusing (convex) mirrors mounted at an angle above solar (thermal) or PV panels. It illuminates the panels additionally with direct sunlight while the sun is low above the horizon. And when it rises, the system radiates them with reflected diffuse-scattered in the atmosphere light only. The Reflector system does not cause any overheating and aging of the panels. It increases their production in periods when they operate at a capacity lower than half of their capacity. The Reflector system uses diffusing (convex) point-focused or line- focused reflectors. Such mirrors have the shape and position ensuring that only within periods after sunrise, prior to sunset and in winter time- only when the sun is low above the horizon, they diffuse the direct sunlight falling on them to the photovoltaic or thermal modules. While, during the rest of the time they reflect the diffused-scattered light.

Description

DESCRIPTION

Reflector system and a convex mirror method for solar and PV systems

Technical field

The invention is related to the field of "Batteries: thermoelectric and photovoltaic with concentrators, orientators, reflectors....". As well as to "Optical elements or arrangements associated with the devices"

U. S. Classification 136/246

Cooperative Classification H01L31/0232. F24J2/067. F24J2/12.

Background technology

It is well known mat productivity is a basic indicator in solar energy. It depends on the time during which sun rays irradiate the receiver - the thermal or photovoltaic system, as well as on their intensity. There are solutions with systems tracking the position of sun. There are also concentrator thermal-photovoltaic systems.

The following patent solutions are known:

US 8642880 B2 - Interchangeable and fully adjustable solar thermal-photovoltaic collector

US 20130146121 Al - Solar light concentration photovoltaic conversion system using a wavelength splitter and lambda-specific photovoltaic cells optically coupled to lambda- dedicated fibers illuminated by respective split beams

CN 102969380 A - Double-sided battery piece based vertical packaged efficient photovoltaic module

CN 202948956 U - vertical packaging efficient photovoltaic module based on two-sided battery pieces

The structure of the solution shown in US 8642880 B2 includes a solar thermal- photovoltaic concentrator system - "Interchangeable and fully movable concentration system for thermal and photovoltaic energy, comprising one or a bigger number of heat collecting elements; one or a bigger number of primary reflectors with one or a bigger number of openings; one or a bigger number of optical mechanisms to direct the primary reflectors towards the sun and between the heat collecting elements and the openings in the primary reflectors; one or a bigger number of PV cells modules on the shady side of the primary reflectors; and one or a bigger number of distribution optical mechanisms, located on the shady side of the primary reflectors. Wherein, after the sun rays irradiate to the primary reflectors, a portion of the sun rays within the range of 0% to 100% are reflected to one or more heat collecting elements, while the remaining rays are directed by the optical mechanisms through the openings of the primary reflectors and are distributed to one or more PV cells modules."

The shown solution WO 2013074805 Al - comprising a concentrating photovoltaic collector

- "A combined solar day light system and a photovoltaic electricity generation system operating in the presence and absence of sunlight. A Photovoltaic (PV) module is mounted on the back of a secondary reflector from the day light system, fixed in a way allowing, when no sunlight is needed, the PV module to be positioned, collect the sun radiation from the primary reflector and convert it into electricity. When sun light is needed for the day light system, the PV module on the back of the secondary reflector receives unconcentrated solar radiation and converts it into electric power, but not in as big a quantity, as in the case when it receives it concentrated by the primary reflector."

The above solutions have the following disadvantages:

- they concentrate the sun rays and capacitate a potential overheating of the modules;

- design complexity;

- regular maintenance is required.

The above listed disadvantages diminish the consumer value of the known solutions and are among the reasons because of which this technology is very poorly spread.

The priorities known are described in the above mentioned patents. None of them includes the system described below.

Technical essence of the invention

The objective of the current invention is to increase the productivity of the photovoltaic and the thermal solar systems when the sun is low above the horizon by increasing their illumination.

The Reflector system invented is not a concentrator. It comprises one or more convex mirrors mounted on the roof ridge with solar or PV panels installed. It irradiates the panels additionally and increases their capacity mainly within time periods when the sun is low above the horizon (in the morning after sunrise, in the evening prior to sunset and in winter time). The design of the Reflector system ensures that it radiates the panels with a reflected direct sunlight when the sun is low above the horizon. While, when the sun rises above the horizon, it does not radiate the panels with a direct sunlight but only with scattered light.

The Reflector system reflects the visible light and does not cause aging and overheating of panels. Thus it enhances their average daily and annual production, while at the same time it does not overheat them and does not decrease their lifetime. The Reflector system is an aggregate of convex mirrors positioned above the top end of PV or thermal modules at an angle to them. The Reflector system uses diffusing (convex) point-focused or linear-focused reflectors. Such mirrors have the shape and location that allow them, only within the time periods after sunrise, prior to sunset and in winter time - only when the sun is low above the horizon, to diffuse the direct sunlight falling upon them to the photovoltaic or thermal modules. And when the sun rises to its zenith - they don't. W

The operative PV or thermal panels may be at any location under or close to the reflectory's base. This includes, but is not limited to, other surfaces such as ship decks, piers, construction roofs or walls, suspended cables, roadways and off-shore structures.

In one of the preferred embodiments of the current invention the reflector(s) is(are) a convex one(s) - parabolic or quasi-parabolic, elliptical, spherical shapes or a combination of such geometries, able to diffuse sun rays.

In other embodiments of the current invention, the inclination of the reflector(s) is adjustable and provides for longer radiation on the panels.

As at the moment of invention, the structure of system's individual components is known. However, the combination between the above specified functions that characterize the suggested system and method is not found in the information available. And precisely that combination of properties, not met previously, allows for new, unknown in the information available, characteristics of the Reflector system, set forth in the current invention description, to be obtained. This combination of design characteristics provides for new consumer and operational properties that are not present in the known decisions and rectifies their faults.

The new properties are reliability, simple structure, continuous operation and efficiency always when the sun is low above the horizon. And during all the time it directs the diffused scattered light to the panels.

Such properties have been achieved due to additional items included - convex mirrors. In the configuration suggested they ensure the achievement of the objectives specified above. Such mirrors have the shape and position that allow them, only within the time periods after sunrise, prior to sunset and in winter time - when the sun is low above the horizon, to reflect the direct sunlight falling on them to the photovoltaic or thermal modules. And when the sun rises higher above the horizon - the reflected light does not fall on the modules but at the reflectors' base /

The technical effect is a result of the invented system's advantages compared to existing models:

- ensures increased production within the periods when the reflected direct sunlight falls on the modules;

- ensures increased production within the periods when the reflected diffused sunlight falls on the modules;

- prevents the modules from overheating within the periods when reflected light does not fall on the modules;

- cost effective - maintenance is identical to the maintenance of the modules - to be washed periodically. They are significantly lower than the revenues from the increased electric power yield. And it is already cost effective to apply it in large PEPS (photovoltaic electric power stations).

- high reliability and repairability (due to the simple structure);

- suitable for mass application due to its low price

- it can be mounted above the rows of modules of existing photovoltaic stations that are in operation. The above stated and some additional advantages of the invention are substantiated by a detailed description considered in conjunction with the Figures attached.

The technical solution of the invention is clarified by means of drawings and diagrams.

Fig. 1 shows a "Reflector system" of modules that are "linear-focused" convex mirror

Fig. 2 shows a "Reflector system" of modules that are "point-focused" convex mirror

Fig. 3 shows a convex mirror module which surface is a part of toroid, paraboloid, ellipsoids, sphere or of another shape.

DESCRIPTION OF THE FIGURES ATTACHED

Fig. 1 shows a "Reflector system" of modules that are "linear-focused" convex mirror. It has a surface-part of a tube with a circle, ellipse or parabola section. It may also be embodied from small plane reflectors that are mounted in the specified shape.

It is mounted above the panels - on the roof ridge. It is not strictly vertical, but is inclined to the panels. Such inclination is specifically calculated for each individual latitude.

Fig. 2 shows individual modules that are "point-focused" convex mirrors. They are appropriately arranged to form a Reflector system. They decrease the effect of sun's horizontal movement on the operative panels.

Fig. 3 shows a convex mirror module which surface is a part of toroid, parabolic, ellipsoids, sphere or of another shape.

DETAILED DESCRIPTION OF PREFERRED EMBODIMENTS

The advantages and characteristics of the current invention and the methods for its embodiment will be easily understood if you refer to the following detailed description of indicative embodiments and the Figures attached. However, the current invention may be embodied in many different forms and it shall not be construed as being limited to the embodiments specified herein.

Embodiments of the invention are described herein in relation to the cross-sectional illustrations that are schematic illustrations of idealized embodiments of the invention. Therefore, variations of the shapes from the illustrations may be expected resulting from, for example, production techniques. Thus, the embodiments of the invention shall not be construed as limited within the specific shapes listed herein, but it shall also include deviations in shapes resulting from, for example, design variations or from manufacture. Therefore, the shapes shown on the figures are schematic ones and they are not intended to show the actual shape of the reflectors and the system and are not intended to limit the scope of the invention.

In the preferred embodiment of the current invention, the distance between the panels and the reflector base can be adjusted. Example N°l

As seen on Fig. 1 an exemplary embodiment of the "Reflector System" invention is made from modules that are a linear-focused convex mirror- Fig. 1

Example N°2

As seen on Fig. 2 another exemplary embodiment of the "Reflector System" invention is made from modules that are "point-focused convex mirror (parabolic, ellipsoid, spherical or of another shape) - Fig. 2

The structure of the Reflector system described provides for the implementation of any of the above mentioned applications. It has been developed based on tests and analysis of the disadvantages of the prototype systems. It is ready to be put into production. The module design allows for the invention to be implemented in large solar power stations.

Invention applications

In one exemplary Application, the "Reflector System" invention is executed in such dimensions that it can be mounted on the roof ridge above the PV panels.

In another exemplary Application, the "Reflector System" invention is executed in such dimensions that it can be mounted above the rows of PV panels installed on the ground - at large PV electric power stations.

The invented Reflector System may be mounted along with the construction of a photovoltaic power station. It can be mounted on complete systems or individual modules that are already in operation.

The only precondition for its operation is to be mechanically fixed above the panels' supporting structure. And this is very easily ensured due to the low weight and wind load.

This, in the opinion of the author, provides for novelty and usefulness of the integrated technical solution suggested.

The expert can easily adopt many modifications of the preferred embodiment of the invention, described in details herein above. Therefore the applicant intends to bind himself only through the scope of the claims attached.

Attachment: 3 Figures

Claims

Patent claims

1. A Reflector system reflecting direct and diffused sunlight to photovoltaic electric power stations and solar thermal modules comprising of a supporting structure and reflectors, characterized by the fact that it comprises only diffusing convex mirrors.

2. A system, in accordance with claim 1, characterized by the fact that the convex mirrors are mounted above the top end of PV modules at an angle to them

3. A system, in accordance with claim 1 , characterized by the fact that the convex mirrors are linear-focused have a half-tube shape with a section in the shape of circle-arc or part of parabola or part of ellipse or part of any other arbitrary curve.

4. A system, in accordance with claim 1, characterized by the fact that the convex mirrors are point-focused and have the shape of a part of a sphere or part of paraboloid or part of ellipsoid or of any other arbitrary shape.

5. A system, in accordance with claim 1, characterized by the fact that the convex mirrors may be formed by multiple flat items arranged in the respective shape.

6. A system, in accordance with claim 5, characterized by the fact that the flat items forming the convex mirrors may be executed under the technology of the insulating units of glass.

7. A method to increase the effectiveness of the photovoltaic and thermal solar modules characterized by the following operations:

- Installation of convex diffusing mirrors above the photovoltaic and thermal solar modules

- Inclination of these convex diffusing mirrors at a certain angle from the vertical line

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