BG61823B1 - BATTERY CURRENT ACTUATOR - Google Patents

Abstract

The device includes a platform (13) with a facility forrotary movement around a vertical axis, a driving unit whichdrives it around it to follow the movement of the Sun, solarenergy collectors fitted on the platform, and concentrators (27)for directing the solar energy to the collectors. Theconcentrators (27) are a plurality of parallel reflectors ofelongated shape fitted on the platform (13), each of them beingparabolic, in order to concentrate the solar energy on ahorizontal focal line. The energy collectors are fitted at thefocal lines of the reflectors. Platform (13) can rest on a fluidtank or an other water receptacle for floating movement on afluid, and liquid for selective sinking of the concentrators (27)can be pumped when it is necessary that they should be protectedfrom adverse atmospheric conditions.

Description

Technical field

The invention relates to a device for the accumulation of radiant energy, in particular to a device for the accumulation of solar energy, which has the means to facilitate its proper orientation to the sun, means of protection against adverse weather conditions and those for its stabilization.

BACKGROUND OF THE INVENTION

In order to use solar energy for heating or to generate electricity, it is generally necessary to concentrate the sun's rays to obtain high temperatures in an environment for energy storage and transport.

There are various methods for concentrating solar radiation. One method uses a round mirror with a parabolic cross section, with the centerline of the reflector pointing at the sun. The parabolic mirror must be fitted in an appropriate manner to allow the sun to follow the celestial sphere constantly.

Correct targeting of the trajectory of the sun through the celestial sphere is variable every day as the slope of the sun changes from summer to winter solstice. Complex mechanisms are required to meet these requirements.

The disadvantage of this method is that solar energy is concentrated in a small, single focal point where a suitable heat absorber is installed, and it is difficult to transport that energy to the point of use.

In another system, long parallel, mirror-covered, concave surfaces with a parabolic cross-section are directed toward the sun. In this system the concentration is realized in a focal line parallel to the linear alignment of the concave concave surfaces. The mirror-coated surfaces are formed either by whole parabolic mirrors or by a series of mirrors. In any case, it is important, from the point of view of focus and efficiency, that the mirrors or series of mirrors are fixed so as not to impair the alignment with the collectors arranged in the focal line of the parabolic reflector. This requires generally large and well-constructed structures.

The collecting reflecting concave surfaces should be oriented north-south and the reflectors installed so that the movement of the sun is followed at different times of the day. Meeting these requirements also requires the use of complex mechanisms.

The solar energy is then collected in a tube containing heat absorbing fluid and mounted on the focal line of the parabolic reflecting surfaces.

In a collector system with concave reflector-shaped reflective surfaces, the reflectors can also be mounted east-west, and then need to be oriented once a day to the sun's trajectory to account for the change in declination. This targeting also entails the requirement for complex mechanisms.

The installed parabolic reflecting grooves in each north-south or east-west configuration are adjusted to maintain their focus on the sun by mounting on an axis parallel to the focal line of the mirror-covered mirrors, and require a large number of supporting, rotating and connecting facilities.

It is absolutely necessary that the reflecting surfaces of the solar energy storage device are located so as not to be subjected to possible damage caused by, for example, hail. This is often the case with the use of high quality and therefore expensive glass bent in reflective mirror designs. In addition, the necessary protection is often achieved by inverting the mirror surfaces away from the incoming hail.

US 4315500 discloses a solar energy storage device in which parabolic reflectors are mounted on a floating structure that is made to adhere to or follow the motion of the sun. The reflectors in this device are subject to possible hail damage or other adverse weather conditions.

Patent BE 773186 describes a floating platform for a port basin that is submerged below the water level so that it is protected against adverse weather conditions. This floating platform, however, is not intended for energy storage applications.

US 4159629 describes a vessel that floats in a reservoir and carries a number of trough-shaped parabolic concentrators to focus energy in radiation absorbing tubes. The vessel is capable of being lowered as the water level changes to protect it from high winds. However, a number of hubs are still at risk of hail.

DE 3633172 describes a similar construction, however, again with parabolic reflectors that always remain exposed to adverse weather conditions.

SUMMARY OF THE INVENTION

It is an object of the invention to provide a device for the accumulation of radiant energy which is of a simplified construction and operates economically.

It is another object of the invention to provide a device for the accumulation of radiant energy in which the concentrators can be maintained in conjunction with the associated collectors.

It is also another object of the invention to provide a device for the accumulation of radiant energy that can be easily protected in adverse weather conditions or in other cases of adverse effects.

Another, further preferred object of the invention is to provide a device for the accumulation of radiant energy that can be simply and easily mounted for the accumulation of radiant energy on areas with large surface area.

Furthermore, it is a preferred object of the invention to provide a low-cost device for the accumulation of radiant energy that is protected from breakage or other damage resulting from excessive deformation.

In accordance with the objectives of the invention, the radiation energy storage device includes a fluid reservoir, a fluid platform, fluid transporters, and a fluid energy collector mounted thereon, these collectors carrying a transmitting energy medium. Reflectors are positioned on the platform for reflecting radiant energy and concentrating solar energy on the radiators.

In addition, according to the invention, the device includes means for selectively submerging the reflectors under the fluid in order to protect the reflectors against adverse climatic conditions. The collectors remain above the fluid in which the reflectors are immersed so that no energy is lost from the collectors.

In one preferred embodiment, the fluid reservoir includes a built-in reservoir such as a storage container or a water basin. Alternatively, the fluid could include water in a river or ocean. The term "fluid reservoir" as used in the description thus includes any of the classifications described above, and the term "reservoir" includes natural or purpose-built liquid containers.

In one embodiment of the invention, a low pressure is set under the platform to keep the platform up from the lifting force of the liquid.

In another embodiment of the present invention, the platform is provided with additional floating or surface-holding devices or means such that, when immersed by flooding, it will move to a stable dynamic position under the liquid without major deformation or inversion.

In another embodiment of the present invention, the floating attachments are firmly fixed to the platform to support it when the reflectors are submerged under the fluid of the tank. In doing so, the lifting power of the floating devices increases by one unit height from the base to the top of the floating devices.

In a preferred embodiment, the floating devices are elongated and fixed to the platform along their length. They narrow outwardly, from the narrow side of the bottom, fitting the platform to the wider side at the top.

In yet another aspect of the invention, the solar energy storage device monitors the movement of the sun by means of moving or rotating the platform.

In another aspect of the invention, the reflectors are formed as a plurality of parallel and elongated reflectors mounted on the platform, wherein each reflector is parabolic and concentrates solar energy in a horizontal focal line, and energy collectors are fixed in the focal lines of the reflectors.

Each parabolic reflector is preferably constructed of a plurality of parallel, elongated reflecting elements, such as mirrors whose cross-section could be arcuate or flat. When using a fluid container, the platform is preferably constructed of flexible floating material so that it is adapted to the flat surface of the fluid, which forms a flat base plane, while keeping the reflectors focused on the associated collectors.

In another aspect of the invention, fluid supply blades located in the reservoir are attached below the platform, which are connected to openings through the fluid pumping platform on the platform and reflectors.

In another embodiment of the invention, each of the fluid delivery propellers is connected by opposing propellers. They work in conjunction with the propellers to pump fluid in the opposite direction. In this case, diverters are positioned between the feed and counter-propellers.

Preferably, the fluid feed propellers have a reverse step to that of the counter-propellers, with the associated feed and counter-propellers mounted and axially spaced on common vertically oriented drive axes.

In yet another aspect of the invention, one or two propellers are connected by a conduit of such configuration that it directs fluid near one or two propellers in a vertical direction and at the other end, at least in part, directs the fluid in a horizontal direction.

There may be a velocity around the platform for the ordinary separation of fluid in the reservoir from the reflectors onto the platform.

Description of the attached figures

A preferred embodiment of the invention is shown in the accompanying drawings, of which:

Figure 1 is a top plan view of a form of solar energy storage device according to the invention;

Figure 2 is a schematic top view of the device showing details of the float control system of the device;

3 is a cross-sectional view of the device along line AA of FIG. 2;

Figure 4 is a top view of a concentrating mirror system for use in the device;

5 is a side view of the system shown in FIG. 4;

Figure 6 is a vertical projection on the side of the system of FIG. 4 and 5;

Figure 7 is a top view showing a floating platform support system;

Figure 8 shows a sectional view of line B-B of FIG. 7 depicting a submerged platform;

Figure 9 is a top view of a large platform system of ten individual parabolic mirror systems, for the sake of clarity avoiding individual mirrors and the upper superstructure;

FIG. 10 is a vertical sectional view of a platform system along lines C-C in FIG. 9 and 11;

Figure 11 is a partial top plan view of a foundation platform and a mirror system as shown in FIG. 9, and a complete view of the CC section of FIG. 9;

Figure 12 is a side elevational view of a water propeller as an assembled assembly in the invention;

Figure 13 is a partial top plan view of the foundation and mirror systems including the propeller assembly of FIG. 12 and

Figures 14 a-c are a side projection, a top view and a side elevation respectively of one of the floating blocks shown in FIG. 10.

Examples of carrying out the invention

In the accompanying drawings, first in Figures 1 to 3, a solar energy storage device 10 according to a preferred embodiment of the invention, comprising a circular water container or reservoir 11, which may for example consist of a body of water or a catchment basin or intentionally a container comprising an outer wall 12 which surrounds and retains water in the container 11. A platform 13 is arranged in the container so that it floats on the water 14 with the level 15 therein. The platform 13 may be constructed of floating material, such as foam material, or mounted on a substrate of such material. Alternatively, the platform 13 may be formed by closed air tanks or provided with another means to make it float.

A rim 16 is attached to the platform 13 or is shaped like a dish with it to form a cup-shaped body that fits snugly to its outer diameter, with the rim 16 extending below its underside.

As can be seen from FIGS. 2 and 3, a channel 17 is formed at the base 18 of the container which closes around it so that it is annular. The outer diameter of the duct 17 is smaller than the diameter of the gum 16, thus forming a pad 19 on which the gum 16 will rest upon withdrawal of water from the container 11.

Guide rollers 20 are mounted around the inner diameter of the container wall 12 so as to maintain the relative position of the platform 13 by clamping it to the crown 16. One or more of the rollers 20 can be driven by a motor to properly rotate the platform 13 when required. adjust the position of the solar energy storage device relative to the sun.

One or more discharge pipes 21 are connected to a suitable pump and valve device 22 so that water from the underside of the platform 13 can be pumped to its upper side by flowing through the outlet openings 24 or to an additional reservoir (not shown) through the pipe bits 23. The speed and direction of the water flow can be controlled by the valve devices to the pump 22. The base 18 of the container 11 is also provided with a channel 25 which is connected to the valve devices to the pump 22 by a pipe 26.

A plurality of sun rays 27 are attached to the platform 13, arranged as shown in FIG. 1, side by side, and each containing, as shown in more detail in FIG. 4 and 5, a series of parallel mirrors 28 of curved or flat shape, inclined at an angle to act as a large elongated parabolic mirror. These mirrors 28 are arranged in order to focus sunlight on an accumulated energy tube 29 above them, such as a black tube, with the collector tube 29 mounted on a suitable frame structure 30 of triangular shape above the mirrors 28. The collector tubes 29 are connected together by a suitable a way to allow, as is known, the accumulation of heat and its continued use in industries, such as the supply of energy to steam turbines in power plants. For this purpose, the collector tubes 29 could transfer heat or energy absorbing medium, such as heat-absorbing oil. The collector pipes 29 and the respective concentrators 27 can be interconnected by a knee and the heated medium transferred through the pipes 29 can be used for steam production. Alternatively, the medium transferred from the collector pipes may circulate in a closed system with heat exchangers that extract heat from the heated medium.

Compensation for minor errors in the adjustment of the concentrating mirrors 28 is accomplished by an arched reflector 31 located above the collector tube 29 and designed to act as a non-reflecting concentrator.

To improve the accumulation of heat from frame members 30 and from other structural components that could block the path of radiated energy that would otherwise fall directly on the concentrating mirrors 28, such components may be attached or may form part of mirror or reflecting surfaces 32 (see FIG. 6), with the surfaces 32 being substantially 90 ° relative to the focal line of the mirrors 28, which then focuses on the collector tube 29 or the reflector 31, as shown in FIG. arrows in Fig. 6.

The platform 13 is preferably constructed of a flexible material such as lightweight, thin foam material. In this way, the platform 13 will maintain a flat plane position during navigation due to its mobility and alignment to the flat surface of the fluid on which it floats. Concentrating mirrors 28 will then retain proper focus or substantially focus on the associated collector tubes 29. Any movement of the platform caused by waves results in corresponding movement of the collector tubes 29, whereby they remain substantially in the focus of the associated collectors. mirrors 28. The use of lightweight and easily adjustable floating material for the platform 13 significantly reduces the cost of the system as it maintains the alignment of the mirrors with their collectors.

As stated above, in order to cause the platform to rotate, one or more rollers 20 must be actuated by a motor. To this end, one of the rollers 20 may be connected to a belt 33 which in this case drives a roller 34 from a servomotor or other actuator 35. The actuation of the servomotor is controlled by a monitoring device 36 of a known type, such as a device with phototransistors or other photosensitive and shading elements that create a shadow on the photosensitivity according to their position relative to the sun. Of course, many other different platforms can be used to control and move the platform 13 depending on the movement of the sun, such as time-sensitive systems.

In operation, when the sun rises to the east, the tracking device 36 will rotate the floating platform 13 to a position where the longitudinal axes of the concentrators 27 are directed toward the solar geographical meridian or horizon, movement is effected by the servomotor or other actuating device 35 triggering washer 34, belt 33 and wheel 20 '. In this way, the longitudinal axes of the concentrators 27 are positioned in vertical planes that intersect the sun. When the sun describes an arc across the sky, its position in the geographical meridian at the horizon will be monitored by the concentrators 27, together with the platform 13 floating in the fluid 14, carrying the concentrators 27, which rotates from the drive system such that the longitudinal axes of the concentrators remain coexistent with the sun. It turns out that, at all times since sunrise, the storage device is exposed to maximum radiant energy from the sun and, therefore, the accumulated energy is maximum. The use of a floating platform 13 allows the device 10 to be moved easily and conveniently to obtain and maintain the setting of the hubs 27 relative to the sun.

If there is a danger of hail or other destructive atmospheric phenomena, the pump 22 switches on and pumps the water from the maximum full container 11 into the storage pool, reducing the platform 13 to a lower level. The cylinder base or crown 16 will then rest on the base of the base 19 of the container 11, which has a largely clogging effect. Then a slight decrease in pressure is carried out under the entire platform and at the same time water is passed through the pipe 24 to the upper surface of the platform 13. The reduced pressure under the platform 13 is maintained sufficiently large to prevent the platform from floating above the water pumped through 24 so that covers the platform 13 and the fixed sun concentrators 27 to protect them from damage.

Alternatively, instead of relying on the reduced pressure of the platform 13 to keep it submerged, mechanical means could be used for this purpose. For example, after immersion of the platform in order to keep the sun concentrators 27 under water and the reflecting surfaces or mirrors 28 of the concentrators to be protected, retaining pins or elements mounted on the outer wall 12 of the container 11 may be provided. retakes of the platform 13 the pins or elements are retrieved. As another alternative, the platform may be provided with one or more chambers or tanks that can be filled with water to submerge it, or filled with air to allow it to float.

The water can be returned to the container 11 by passing it through a pipe 26 into the channel 25. Since the platform 13 has a degree of elasticity, the water directed to the channel 25 centrally below it will slightly raise the central portion of the platform and thus will provide efficient and rapid drainage of water when re-exposure to concentrators 17 in the sun is required.

Figures 7 and 8 show a floating support system for the platform 13 when the latter is mounted on large masses of water, such as a lake, bay, river or the like. The platform 13, as before, includes a plurality of stacked hubs 27, only one of which is shown in full. In this embodiment, the platform 13 is provided around its periphery with a protruding crown 37 that terminates at its upper end with a floating element 38 or alternatively with a series of floating elements 39. In the embodiment shown, the element 38 is annular and may comprise foam material extending completely around the gum 37. Furthermore, floating elements 39 may be coupled to any parabolic concentrator 27 and arranged at a central, normally shaded area of the concentrators 27. Preferably, the elements 39 are mounted on the stems 40 so as to be at a distance from the mirrors 28 of the concentrators 27. The elements 39 preferably consist of sections of foam plastic material of elongated shape and the stems 40 firmly holding them. Alternatively, the stems 40 may consist of short pieces of wire or other flexible attachment.

When immersion of the platform 13 is desired, as shown in FIG. 8, in the aforementioned adverse atmospheric conditions, water is simply pumped to its upper surface by any suitable means, such as a conventional pump. Alternatively, the platform 13 may be provided with one or more delivery and drainage units 41, as shown in FIG. 8. Each assembly contains an opening 42 through the platform 13, coaxially arranged with a finger-shaped cylinder 43, which protrudes from its underside 3. Inside the cylinder 43 and immersed in the fluid therein is a propeller 44 connected to a drive motor. 45, fixed in any suitable way, such as by a support stand 46 on the top side of the platform 13. When the motor is started in the first direction, water will be pumped from the bottom side of the platform 13 to its upper side, through the cylinder 43 and the opening 42 When drainage of the pl 13, the motor 45 is driven in the opposite direction, which rotates the propeller 44 in the opposite direction and the water is pumped through the opening 42.

The pumped water on the platform 13 will be retained on the platform 37 so that the platform will begin to sink. If the walls of the platform 13 begin to sink first, they will be retained by the floating crown element 38. Water pumping on the platform 13 may be continued to submerge the concentrators 27 until a stable dynamic equilibrium is achieved with sections of the platform 13 between the crown 37 will be supported by the floating elements 39. The platform 13 will again come to the surface of the mass of water to expose the concentrators 27 to the sun after the water retained by the crown 37 has drained.

In FIG. 9 is an alternative top view of the invention, comprising a typical foundation, avoiding the plurality of individual reflector mirrors and the solar energy storage system above them with mounting elements. These elements are shown in FIG. 9, which depicts a floating base 52 in which the grooves or panels 53 are formed at different angles and on which flat strips of mirrors 54 are attached. These mirrors 54 and their adjacent grooves are arranged at such an angle as to concentrate the rays of radiated energy. (usually sunlight) 55 on the solar energy tube 56. In addition, if the setting of the mirrors 54 is slightly offset, the sun's rays 55 will fall on the reflector screen 57 and back on the solar energy tube 56.

The solar energy tube 56 and the reflector screen 57 are mounted on a suitable frame structure 58, which is mounted directly on the foundation layer 52 in a row. Alternatively, the frame structure 58 can be indirectly mounted on the foundation, such as by mounting the frame structure 58 to the floating units 59, themselves being mounted directly to the base 52.

In normal operation, the foundation 52 will float in a reservoir with a relative water level indicated by the reference number 61. Of course, the reservoir could be any suitable mass of water, whether it is an artificial pool, a natural bay, a river mouth or a dam.

If the atmospheric conditions indicate that the mirrors 54 are to be protected from possible hail damage, then water from the tank 52 is pumped to the upper surface of the tank by appropriate means.

The outer diameter of the foundation 52 (or the outer edge, if not circular in configuration) has a narrow wall attached to it or forming part of the foundation 52 defined by a floating block 52 composed of a suitable floating medium such as porous polystyrene. Also, further elongated floating blocks 60 are mounted and fixed to the base 52 along their length. These floating blocks 60, as best illustrated in Figures 14 a-c, have slots or slots 63 in their lower surface (see also Fig. 11).

In addition, it should be understood that the foundation 52, although it is a single block from the point of view of the invention, can be implemented by forming large foundations 52, by combining long, parallel individual foundations, which are attached together on each in a suitable manner, as exemplified by reference numeral 64 in FIG. 10.

Positioned within the limits of the foundation 52 and connected to the openings 52 passing through the platform 52, propellers 65 and 66 are mounted on a drive axle 67, driven by a suitable motor 68, which in turn is mounted appropriately, as shown by the clamp 69, to platform 52 (see Figs. 12 and 13). The upper propeller 65 and the lower propeller 66 preferably have a reverse inclination of their blades for purposes which will be described hereinafter.

The openings 70 are located at the base of the base 52 so as to allow the flow of water from the underside of the base 52 to flow over the base 52 and back. In a preferred embodiment shown in FIG. 12, the base 52 itself is made of sufficient floating material to support the device with the mirrors 54 above the water level. The openings 70 may therefore be opened as shown.

If, alternatively, the foundation 52 is required to have greater buoyancy in order to maintain the mirrors 54 above the water level during normal operation, the foundation 52 may be shaped like a boat with an outer crown that closes a volume that displaces sufficient fluid so that the level of the water surrounding the foundation not to exceed the top of the crown and thus the mirrors 54 will not be covered with fluid, although they may be positioned at a lower level than the level of fluid around the foundation. In this alternative embodiment, the openings should preferably be closed during normal operation. This could be done by introducing properly operated valves to open or close the openings according to the required operating conditions.

An additional pipeline or conduit 71 may also be included to assist directional water flow, with pipeline 71 positioned between propellers 65 and 66. Another pipeline system 72 is recommended near one or more lower propellers 66, which the pipeline system 72 is suitably mounted to direct the vertical flow of water through the propeller 66 into a horizontal stream, thereby allowing the movement of the foundation 52 to be controlled. The control can thus be accomplished by introducing a single pipeline system Theme 72, which may be selectively guided, or alternatively, may be provided by supplying the system with compound propellers 66, each differently directed, whereby movement will be controlled by actuating only selected propellers.

External actuation of the base 52 may be provided, which would be within the scope of at least one aspect of the invention. For example, if the base 52 was located in a pool where it could be safely located near its side, the movement of the base 52 to follow the movement of the sun could be accomplished by appropriate propulsion at the side of the pool, which joins the base , as shown above in the exemplary embodiment of FIG. 2 is 3.

The operation of the preferred embodiment of the device described is as follows.

In normal operation, when the mirrors 54 are sunshine, the relative water level between the foundation 52 and the tank in which the foundation is floating should be indicated by heading 61. The orientation of the foundation 52 can be conveniently controlled according to the position of the the sun through pipeline 72 as previously described.

If the atmospheric conditions indicate the possibility of damage to the mirrors 54 due to, for example, hail, then the motors 68 are activated to pump water from the tank through the opening 70 onto the upper surface of the foundation 52.

Naturally, the tendency is to concentrate the water in special sections so that the base 52 is immersed as much as possible at the location of the openings 70, together with the mirrors 54 located at higher sections which are still exposed to danger impact of time. However, the construction of the floating blocks is such that they are generally oblique with a smaller cross section at the base to a larger cross section at the top. This tapered configuration causes a concentration of water in each individual section of the upper surface of the foundation and provides a uniform depth of the protective water layer on all mirrors 54. Thus, the mirrors 54 will be fully protected from water at the level shown in FIG. . 10 with position 62. Indeed, the tapered configuration of floating units 59, 60 provides a thick and evenly thick layer of water maintained throughout the pouring process. In addition, the uniform pouring of water on the upper surface of the foundation 52 is aided by openings 63 cut at the base of the floating blocks 59, 60, which openings 63 allow the pumped water on the foundation 52 to circulate over the entire foundation.

However, it should also be borne in mind that floating units 59, 60 can alternatively provide the desired graded lift by stepping, rather than by gradually narrowing or narrowing on one side only. However, in such a configuration, it is extremely advisable that the horizontal cross-section of the floating blocks be the same for all blocks at any distance from the foundation 52.

During the risk period for the mirrors 54, the motor 68 must be kept operable at a sufficient speed at which the upper propellers 65 can maintain the level 62 of the protective layer of water on the mirrors 54.

After passing the risky situation for mirrors 54, motor 68 can be switched off. Due to the natural lifting power of the foundation 52, shutting down the propeller 65 will allow it to flow back through the openings 70, so that the foundation will eventually be drained, with the mirrors 54 open and again able to reflect solar energy to the collector tube 56. In addition, in the preferred embodiment, the attachment of the individual sections forming the base 52, as denoted by 64, may lead to water leaking through them, although such leakage will obviously be sufficiently reduced by the action of the propeller and 65 that are able to keep the water at the desired level 62 during the time when the mirrors 54 need protection. It should also be appreciated that the action of floating units 59, 60 to maintain the water surface level on the foundation 52 will further assist in preventing the formation of wet sections of retained water on the foundation 52, which interfere with the efficient operation of the device .

In order to accelerate the melting process, the motor 68 may be reversed and cause the propeller 65 to direct downward flow of water through the opening 70. Such an operation could also be used to the previously described alternative embodiments of the invention (where the foundation has a vessel configuration) in which the propeller 65 will perform the function of a cleaning pump to remove the water from the foundation.

During operation of propellers 65, rising water flow through openings 70 tends to locally flood the foundation in an area close to openings 70 and propellers 65. The reverse curvature of other faces 66 rotating on the same drive axis 17, however, prevents this action, creating a counterbalancing force. By appropriately adjusting the relative inclination of the curvature and the surface of the blades of the associated propellers 65, 66, the foundation can be safely maintained in a horizontal position despite the forces resulting from pumping on the foundation during adverse weather conditions.

Provided that the rotation of the propellers 65, 66 is required to remove the water from the foundation 52 after the passage of adverse weather, the vertical forces introduced by the two propellers 65, 66, in the opposite direction of the lower propellers 66, counterbalance, thereby there is no lifting of the base 52 at the location of the openings 70, whose configuration tends to collect fluid fluidly in the low areas of the base 52, away from the openings 70.

Of course, due to the opposite effect of the propellers 65, 66 connected to one axis, the additional conduit 71 introduced acts to separate the counter fluid flows obtained by the rotation of the propellers.

Thus, the invention provides a device for the accumulation of solar energy, which is relatively inexpensive to construct, and provides an efficient system for maximizing the accumulation of radiated solar energy. The device can be constructed from inexpensive and easily accessible materials and for a wide range of industrial energy production applications. Alternatively, the device can be adapted for standalone home use. The description assumes that solar concentrators essentially operate normally horizontally. However, they may, in some circumstances, be inclined to the horizontal, but still, when operating, lie at right angles to the vertical planes crossing the sun.

In addition, it should be understood that the device of the invention, although adapted for the accumulation of solar thermal energy, can also accumulate other types of radiant energy that may be concentrated.

The fluid on which the platform is supported for floating motion is preferably placed in a tank. However, it may cover any other mass of fluid such as water in a river, sea or other reservoir.

Although the embodiment described herein is based on the appended drawings, all other modifications and variations thereof should be considered within the broad scope and scope of the invention as set forth herein in the appended claims.

Claims (15)

1. A device for accumulating radiant energy, comprising a fluid reservoir (11), a platform (13) floating on a fluid in the reservoir (11), means for moving the platform (13) in the reservoir (11), radiant energy collectors (29) mounted on the platform (13) and carrying an energy-transferring medium, reflectors (28) located on the platform (13) and positioned to reflect radiant energy and concentrate solar energy onto the collectors (29), characterized in that it includes means for selectively immersing the reflectors (28) under a fluid to protect the reflectors (28) against adverse weather conditions, the collectors (29) being positioned above the fluid in which the reflectors (28) are immersed, so that there is no loss of energy from the collectors (29). 2. Device according to claim 1, characterized in that the platform (13) includes floating devices for sufficiently maintaining the reflectors (28) above the fluid level in the tank (11). 3. Device according to claim 1 or 2, characterized in that the immersion means include means (22, 44) for pumping fluid into the platform (13) and means for maintaining it on it and the reflectors (28). 4. Device according to claim 3, characterized in that the means for maintaining the fluid include devices (22) for establishing a low pressure under the platform (13), to ensure its position below the fluid level. 5. A device according to claim 3, characterized in that the pumping and supporting means comprise fluid-supplying propellers (44, 65) mounted below the platform (13) and connected to openings (42, 70) through the platform (13). 6. A device according to claim 5, characterized in that it includes counter-directing fluid propellers (66) connected to each fluid-supplying propeller (65) and operating to force fluid in a direction opposite to that of the fluid-supplying propellers (65), and in that it is provided with deflectors (71) between the propellers (65 and 66). 7. A device according to claim 6, characterized in that the fluid-feeding propellers (65) have a pitch opposite to that of the counter-acting propellers (66), and the connected feeding propellers (65) and counter-acting propellers (66) are mounted and axially spaced on common, vertically oriented drive axes (67). 8. A device according to claim 5, characterized in that the pumping and maintenance means comprise a conduit (72) connected to at least one propeller (66) and connecting two openings of the conduit, the conduit (72) directing fluid in a vertical direction through an opening adjacent to at least one propeller (66) and directing fluid through the other opening, at least partly in a horizontal direction. 9. A device according to any one of claims 1 to 8, characterized in that the platform (13) comprises a rim (37) for simple separation of fluid in the reservoir (11) from the reflectors (28) on the platform (13). 10. A device according to any one of claims 1 to 9, characterized in that floating adjustment devices (60) are mounted on the platform (13) for maintaining the platform (13) in a substantially horizontal position when the reflectors (28) are submerged under the fluid. 11. A device according to claim 10, characterized in that the lifting force of the floating devices (60) per unit height is increased from the base to the top of the floating devices (60). 12. Device according to claim 10 and claim 11, characterized in that the floating devices (60) are of a length 10 g shape and are secured to the platform (13) along their length, the devices being tapered externally, from the narrow side at the bottom adjacent to the platform (13) to the wider side at the top. 15 13. A device according to any one of claims 1 to 12, characterized in that the reflectors (28) are made up of parabolic reflectors having a focal line, and the collectors (29) are mounted substantially in the focal line of the respective reflector (28). 14. A device according to claim 13, characterized in that the reflectors (28) comprise a plurality of adjacent reflectors. 25 reflector elements of elongated shape, defining an essentially parabolic reflecting trough. 15. Device according to claim 14, characterized in that the collectors (29) are 30 attached to a frame structure (30), essentially at the focus of the thus formed reflecting trough, this frame structure (30) further comprising reflectors (31) for directing the radiant energy towards the collectors (29). 16. A device according to any one of claims 1 to 15, characterized in that the collectors (29) comprise elongated tubes adapted to carry the energy-transmitting medium.