Patent Publication Number: US-2011073105-A1

Title: Modular thermal water solar panel system

Description:
CROSS REFERENCES TO RELATED APPLICATIONS 
     The present application claims the benefit of U.S. Provisional Patent Application Ser. No. 61/246,054, filed Sep. 25, 2009 (Sep. 25, 2009). 
    
    
     STATEMENT REGARDING FEDERALLY SPONSORED RESEARCH OR DEVELOPMENT 
     Not applicable. 
     THE NAMES OR PARTIES TO A JOINT RESEARCH AGREEMENT 
     Not applicable. 
     INCORPORATION-BY-REFERENCE OF MATERIAL SUBMITTED ON A COMPACT DISC 
     Not applicable. 
     SEQUENCE LISTING 
     Not applicable. 
     BACKGROUND OF THE INVENTION 
     1. Field of the Invention 
     The present invention relates generally to solar power collection panels for use in heating water. More specifically, the present invention is a system that collects solar power and structure-generated heat in a solar panel assembly and transfers a portion of the collected heat energy to water flowing through a manifold of tubes. The solar panel assembly is configured for scalability, arranged to simply and easily allow multiple instances (modules) of the assembly to be connected or coupled in an array for increasing the overall heating capacity of the system. 
     2. Discussion of Related Art Including Information Disclosed Under 37 CFR §§ 1 . 97 ,  1 . 98   
     Capturing and using solar radiation energy to heat water is well known. With the continual rise in the costs of commercial energy generation, and in view of the potential threat of global climate change and atmospheric pollution due to the overuse of fossil fuel energy sources, the demand for solar energy water heating systems is increasing. 
     A key limitation in currently available thermal water solar systems, however, is that the commercially available solutions are very costly and require professional expertise for installation (further increasing the initial installation and future expansion costs of such systems). Thus, various solutions have been proposed to address the high cost and complexity of installing solar panel systems. 
     For example, in U.S. Pat. No. 6,948,687 (Shatzky, Sep. 27, 2005) discloses a solar panel system for installation on a building rooftop which is purportedly inexpensive and easy to install initially. The invention by Shatzky is adaptable to many of the various types of roofing surfaces to which a solar panel may be attached. However, while Shatzky discloses an inexpensive and adaptable mounting mechanism, it does not enable the installer to easily connect multiple instances of the same solar panel assembly into a single array in a modular fashion. Shatzky also fails to appreciate the need for (and thus does not disclose) apparatus to accommodate and tolerate the expansion of structural elements and connectors. For a modular system, there is needed an expansion clip or comparable device that fits into the mounting mechanism and that allows expansion and contraction of the solar panel assembly without compromising the integrity of the connections in the assembly. 
     Further, U.S. Patent Application 20080310913, by Urban, et al., teaches a “fixture for attaching a profile rail having an undercut longitudinal groove to another component, as well as an arrangement of this fixture.” The Urban et al application details a fixture “that can generate a statically-sound attachment universally between the profile rail and components, and is at the same time particularly fast and simple to install, as well as inexpensive to fabricate.” The primary goal of the invention is to reduce costs and complexity of installation for mechanisms for attaching a solar panel to a structure. 
     Again, however, Urban fails to disclose a solar panel assembly where the installer can easily connect multiple instances of the same module for the solar panel assembly into a connected solar panel array. And as with Shatzky, Urban et al fail to appreciate the need for (and thus do not disclose) an expansion clip or comparable element that fits into the mounting mechanism and that allows expansion and contraction of the solar panel assembly during temperature fluctuations without compromising the integrity of the connections in the assembly. 
     None of the known prior art, taken either singly or in combination, describes or suggests the present invention as described herein. 
     What remains after consideration of the prior art is an inexpensive solar panel assembly that has a coupling and connecting system facilitating the addition of multiple instances of the same general solar panel assembly to form a single operative array. Such a connection increases the overall surface area used for collecting heat energy, and thus the overall system capacity for heating water. 
     Additionally, what is needed is a solar panel assembly that allows the end user to purchase only as much solar energy capturing capacity (in terms of solar panels) as is necessary, thereby allowing the end user to expand the solar panel array (and its capacity) only as needed, in small, affordable increments. 
     What is also needed is a means for mounting a solar panel assembly to a structure, wherein the attachment mechanism is easy to install and mechanically secures a solar panel assembly in a way that keeps the assembly mechanically stable and secured through a wide range of environmental temperature changes and wind conditions. Such a solar panel assembly mounting means should also be easy to dismantle and disassemble for maintenance or system expansion purposes. 
     These features, and others, are found in the solar panel assembly described in the present application. 
     BRIEF SUMMARY OF THE INVENTION 
     The present invention is an inexpensive modular solar panel system arranged so as to facilitate the connection of multiple instances of the same solar panel assembly in a single connected array to increase the overall surface area used for collecting heat energy, and thus the overall system capacity for heating water. The connection and coupling features allow the end user to expand the solar panel array (and its capacity) only as needed, in small, affordable increments. The end user needs to purchase and add only one, or a few new panels to the array as necessary or desirable. This reduces the cost and complexity for each system expansion. 
     The solar panel assembly of the present invention utilizes radiated energy from the Sun, as well as the heat energy radiating (and convectively transferred) from the structures to which the assembly is mounted, to raise the temperature of water. The inventive solar panel may be used to reduce the amount of commercial energy required to heat a swimming pool, spa, or domestic water supply. 
     When the solar panel is installed in a location where maximum exposure to the Sun is possible, the top surface of the panel is heated by the Sun&#39;s radiated energy, and some of the heat energy of the heated panel is transferred to water flowing through a manifold of tubes integrated in the panel. 
     The effectiveness of the thermal water solar panel of the present invention is increased when it is installed on the roof of a house, or a similar structure, where heat energy radiating and rising convectively from the structure is transferred to the bottom surface of the panel. This heat source adds to any heat energy acquired by solar insolation, thus increasing the overall amount of heat energy available for transfer to the water flowing through the manifold of tubes that are integrated into the solar panel assembly. 
    
    
     
       BRIEF DESCRIPTION OF THE SEVERAL VIEWS OF THE DRAWINGS 
       The invention will be better understood and the objects and advantages of the invention other than those set forth above will become apparent when consideration is given to the following detailed description thereof. Such description makes reference to the annexed drawings wherein: 
         FIG. 1  is an exploded upper perspective view showing the structural and functional elements comprising the overall invention; 
         FIG. 2  is a detailed upper cross-sectional perspective view showing a how a plurality of the inventive solar panel modules are mechanically coupled; 
         FIG. 3A  is an exploded upper front perspective view showing the inventive clamp base and clamp top used for mechanical coupling; 
         FIG. 3B  is an exploded upper rear perspective view showing the clamp base; 
         FIG. 4  is an upper perspective view showing the discretely molded expansion clip used in connection with the clamp shown in  FIG. 3 ; 
         FIG. 5  is an upper perspective view showing how the solar panel assembly is secured into the mounting mechanism; 
         FIG. 6A  is a perspective view showing an alternative embodiment of the inventive clamp, in which the expansion clip is integrally molded into the clamp top; 
         FIG. 6B  is a perspective view showing the clamp of  FIG. 6A  employed in clamping large diameter tubes; and 
         FIG. 7  is a perspective view showing the connecting of tube clips by the tube clip bridge. 
     
    
    
     DETAILED DESCRIPTION OF THE INVENTION 
     Referring now to  FIG. 1 , there is shown in an exploded perspective view the components comprising two instances (or modules)  100   a ,  100   b , of the tube manifold assembly of the present invention. It can be seen that each one of a first and second tube manifold assembly  100   a ,  100   b  includes an array of small-diameter tubes, which is termed the thin tube array. Two such arrays  114 ,  115 , are shown in this view, each showing the thin tubes disposed in substantially a single plane and connected at each end to a fluid port disposed on the interior side of each large tube manifold. This brings the thin tubes  102  of the thin tube arrays  114 ,  115  into fluid communication with each of two opposing large tube inlet and outlet manifolds  101   a ,  101   b . The fluid ports are disposed in a generally linear row along each interior side of the large tube outlet and inlet manifolds. In a first embodiment, the large diameter tubes comprise, respectively, a large tube inlet manifold,  101   a  and  101   a ′, and a large tube outlet manifold  101   b  and  101   b ′, for the first and second manifold assemblies, respectively. The large tube inlet and outlet manifolds lie in generally the same plane as the small diameter tubes, have a longitudinal axis perpendicular to the longitudinal axis of the smaller-diameter tubes. Each thin tube array  114 ,  115  opens into a large tube manifold  101   a ,  101   a ′,  101   b ,  101   b ′ at each end, allowing water forced into the large tube inlet manifolds  101   a  and  101   a ′ to flow through the multiple instances of thin tube array  114 ,  115  into a first large tube outlet manifold  101   b  and then into a second  101   b ′ and successor (if applicable) large tube outlet manifolds. With one end of the connected large tube inlet manifolds blocked (e.g. capped or plugged), as pressurized water flows into one large tube manifold  101 , it passes through the multiple instances of thin tube array  114 ,  115  into the large tube outlet manifolds  101   b ,  101   b ′ and then out the open end of the large tube outlet manifold. In this manner, water is forced through the both the large tube manifold assemblies and thin tube arrays. As radiated heat energy is captured by the multiple instances of thin tube array, at least some portion of this absorbed heat is inductively transferred to water flowing through those instances of the multiple instances of thin tube array. 
     Preferably, the tube manifold assembly is fabricated from generally rigid extruded plastic tubing, which is an efficient material for absorbing radiated heat (such as from the Sun). 
     The tube manifold assembly can be made in various lengths (measured as the length of the two parallel instances of thin tube array  114 ,  115 ). For instance, 3.9 meter, 3.4 meter, 2.9 meter, and 1.4 meter lengths are particularly useful in residential housing applications. Additionally, while a generally linear relationship of connected large tube inlet and outlet manifolds is contemplated, the system will easily accommodate direction changes with angled or curved fittings, wherein field cut or predetermined intermediate lengths of large tubing are provided to bring the ends of the inlet outlet manifolds of subsequently placed modules into alignment. 
     It can also be seen, in  FIG. 1 , that there are multiple instances of thin tube clip  102 , each oriented parallel to the large tube manifolds  101   a  through  101   b ′ et seq., and extending transversely across all instances of thin tube array  114 ,  115 . The thin tube clips  102  are spaced apart from one another and are preferably distributed generally evenly between each of the large tubes  101   a  through  101   b ′ et seq., and are used to hold the thin tube arrays in a parallel orientation. The thin tube clips are linear rods or sticks with comb-like tines or fingers that engage and capture the sides of each thin tube with a snap fit connection. 
     When two modules of the tube manifold assembly are connected together, thin tube clip bridge  103  is used to mechanically connect the ends of aligned thin tube clips  102  with a snap or friction fit coupling, thus providing additional stability and strength to the combined assemblies. As seen in  FIG. 1  and  FIG. 7 , the thin tube clip bridge includes a base with a U-shaped channel running longitudinally and into which the thin tube clip is inserted with a snap or friction fit connection. 
     Mounting clamp base  104  is used to mount the tube manifold assembly to a building roof or other surface. Mounting clamp base  104  includes a generally flat bottom and can be secured to a roof by using screws to directly attach it, or by bolting it to any appropriate adaptive mechanism. After the mounting clamp base  104  is attached to a roof or other surface, large tube manifolds  101   a  through  101   b ′ and more, if provided, are positioned to rest in the arcuate cradle of mounting clamp base  104 , thus orienting the plane of the entire assembly substantially parallel to the surface upon which it is mounted. 
     Once the large tube inlet and outlet manifold assemblies are positioned to rest in the cradle of the mounted mounting clamp bases  104 , a mounting clamp top  105  is placed over each mounting clamp base  104 , and then snapped onto the mounting clamp base  104  to secure itself around a portion of the large tube manifold. The mounting clamp top, like the mounting clamp base, includes an arcuate interior portion that wraps around a portion of the large tube manifold. Accordingly, mounting clamp base  104 , and a corresponding mounting clamp top  105 , are shaped to form a pair of opposing arcuate jaws that capture and retain the bottom, one side, top, and a portion of the opposite side of a large tube manifold. They are provided with coupling elements that allow mounting clamp top  105  to be snapped into a locking engagement with mounting clamp base  104  (see details of this locking engagement in the description of  FIG. 3 ). 
     Additionally, the locking engagement between a mounting clamp top  105  and a mounting clamp base  104  can be unlocked with ease, and the two pieces can be pulled apart to allow the entire tube manifold assembly to be removed from an installed array. Note, however, that while mounting clamp top  105  and a mounting clamp base  104  can be unlocked with ease, the process requires specific mechanical actions that cannot be accomplished by wind, ambient temperature, or small animal activities. Therefore, they will not become unlocked inadvertently under ordinary environmental conditions. 
     Once a tube manifold assembly is installed onto a roof or other surface, one end of a first large tube outlet manifold  101   b  is sealed off using water input tube sealing plug  107 , and the opposite end of the second large tube inlet manifold  101   a ′ is sealed off using water output tube sealing plug  113 . This leaves open one end of one of the large tube manifolds in the overall tube manifold assembly. A source of pressurized water is attached to the open end of the first large tube inlet manifold  101 , and a water outlet line or hose is connected to the open end of the second or subsequent large tube manifold  101   b ′ (or open end of a successor large tube inlet manifold, depending on the flow pattern desired), thus allowing heated water to exit the assembly and flow to a desired destination. 
     Rather than having an end capped, each instance of large tube manifold  101   a  through  101   b ′ of a tube manifold assembly, can instead be coupled with an identical large tube manifold  101   a ″ and  101   b ″ (not shown) of another instance of a tube manifold assembly by using a manifold coupling adapter  106  and lock nut  108 , along with one each of large O-ring  109  and small O-ring  110 . This is possible because each large tube manifold of the tube manifold assembly has one end threaded internally, and its other end threaded externally, in an arrangement that allows the assemblies to be threadably coupled using threaded fittings. 
     The external threading of manifold coupling adapter  106  can be screwed into the internal threading of a large tube manifold  101  of the tube manifold assembly using, for instance, a small O-ring  110 , to seal the connection. With the small opening of lock nut  108  disposed between the flange of manifold coupling adapter  106  and the lip of large tube manifold  101   a , lock nut  108  is still rotatable, and its large opening has internal threads sized to mate with the external threading of a second large tube manifold  101   a ′ of a large tube outlet manifold. In this configuration, the rotatable lock nut  108  is used to physically secure the large tube manifold of one tube manifold assembly to the externally-threaded end of a second large tube manifold of another tube manifold assembly. Large O-ring  109  is used to seal the connection between the connected ends of large tube manifolds with the flange of manifold coupling adapter  106 . 
     Coupling first and second instances of the tube manifold assembly in this manner in this way provides a reliable waterproof seal where the large tube manifold assemblies of each large tube inlet and outlet manifold assembly are joined together, while expanding the water heating capacity of the system. 
     In the prior art, where rigid tubes are used in a solar panel assembly, the method of sealing one tube to another is through the use of a clamp and gasket combination. The present invention uses a method of attaching (and sealing) one large tube manifold to another (for attaching two solar panel assemblies into a single array), which has a higher degree of reliability and is easy to use when installing the assemblies on a roof. 
     In an alternative installation, every other end of both the large tube inlet manifolds and the large tube outlet manifolds can be capped in a staggered pattern, such that water flows first into the first large tube manifold assembly  101   a , then through the first thin tube array  114 , then into and through the first large tube outlet manifold  101   b , into the second large tube outlet manifold  101   b ′, through second thin tube array  115 , into second large tube inlet manifold  101   a ′, and then either out for recirculation or into the next large tube inlet manifold of connected successor modules. This back and forth, or sinuous flow pattern of the water through the system maximizes the time available for heat transfer from the tubes to the fluid. To accomplish the staggered pattern, a disk element or other closure can be provided as a fitting or part of a fitting interposed between connected inlet or outlet manifolds. For instance, lock nut  108  can be provided with a disk closure in its center, rather than being open. Thus, while providing a means to couple large tube manifolds, it can also be employed to stop water flow to a successor large tube manifold and thereby force water through two small tube arrays before it is returned to the successor tube. In this way, water will travel through a number of small tube arrays before leaving an outlet for use. 
     Referring now to  FIG. 2 , there is provided a more detailed cross-sectional view of how multiple instances of the solar panel assembly are mechanically connected. Here it can be seen that large tube outlet manifold  101   b  of one tube manifold assembly is connected to a second large tube outlet manifold  101   b ′. The first large tube outlet manifold  101   b  is mounted to a surface and is secured by mounting clamp base  104  and mounting clamp top  105  in cooperation with expansion clip  400 . The thin tube arrays  114 ,  115  extend perpendicular to the rigid large tubes  101   b ,  101   b ′ of each instance of large tube outlet manifold, and they are secured in substantially the same plane by thin tube clip  102 . Thin tube clip bridge  103  connects instances of thin tube clip  102  between the two connected rigid tube manifold assemblies [see also  FIG. 7 ]. 
     The connection between the first and second instances of the large tube manifolds is accomplished as follows: 
     First, small O-ring  110  is positioned between the first large tube manifold  101   b  and manifold coupling adapter  106 . Next, the small opening of lock nut  108  is disposed over the threaded end of manifold coupling adapter  106 , with the large opening lock nut  108  oriented to face the unthreaded end of manifold coupling adapter  106 . The outside threads of manifold coupling adapter  106  are then screwed into the inside threads of large tube outlet manifold  101   b . This seals the connection between the first large tube outlet manifold  101  and the threaded side of the flange of manifold coupling adapter  106 , while allowing lock nut  108  to rotate, yet keeping lock nut  108  secured behind the flange of manifold coupling adapter  106 . Following this, large O-ring  109  is positioned between the second large tube outlet manifold  101   b ′ and the non-threaded flange of manifold coupling adapter  106 . Next, the exterior-threaded end of the second large tube outlet manifold  101   b ′ is butted up against the non-threaded side of the flange of manifold coupling adapter  106 . Finally, the interior threads of lock nut  108  are threaded onto the exterior threads of the second large tube outlet manifold  101   b ′. This action compresses large O-ring  109  between the flange of manifold coupling adapter  106  and the end of the second large tube outlet manifold, thereby creating a watertight seal. This also causes the two large tube manifolds to easily be connected in a physically secure manner. 
     As can be seen in  FIG. 2 , connecting additional instances of the rigid tube manifold assemblies is easily done by simply repeating the process with each new assembly that is added to the array of assemblies. 
     Referring now to  FIG. 3A  and  FIG. 3B  there are show exploded views of the mounting clamp assembly used to secure the solar panel(s) to a surface. In these drawings, mounting clamp base  104  has a pair of mounting holes  301  that are used for securing mounting clamp base  104  to a surface. 
     Once mounting clamp base  104  has been secured to a surface, a large tube manifold  101  is positioned to rest in the cradle of mounting clamp base  104 . Then, expansion clip  400  is secured to mounting clamp top  105  by snapping split round protrusion  403  into a snap fit connection in the round receptacles  306  found on mounting clamp top  105 . Note that, alternatively, mounting clamp top  105  can have its split round protrusions  403  snapped into mating round receptacle  306  found on mounting clamp top  105  during the manufacturing process at the factory, thus not requiring this step to be performed during the installation. In the alternative, and as shown in  FIGS. 6A-6B , expansion clip  400   a  can be integrally molded into clamp top  105   a , obviating the need for the above-described structural elements needed to connect a discretely molded expansion clip to the clamp top. 
     With either version of expansion clip  400 / 400   a  secured to mounting clamp top  105 / 105   a , mounting clamp top  105  is positioned over the top of the instance of large tube outlet manifold  101   b . Pressing mounting clamp top  105  down onto the mounted instance of mounting clamp base  104  causes tension on expansion clip  400 / 400   a  as it is compressed between mounting clamp top  105 / 105   a  and the exterior wall of large tube manifold  101   b . Rectangular guide  302  provides a guiding protuberance for easily sliding rectangular guide  302  into rectangular receptacle  303 , thus causing the instances of locking base clip  304  to clip into base clip slot  305 . This latches mounting clamp top  105 / 105   a  onto mounting clamp base  104 , thus securing large tube outlet manifold  101   b . Note that the tension of expansion clip  400  or  400   a  against the exterior wall of large tube outlet manifold  101   b  allows for some expansion and contraction of large tube manifold  101  without losing the secure hold that keeps large tube outlet manifold  101   b  in position. It will be readily appreciated that the clamping system described is identical for each large tube inlet and outlet manifold. 
     Referring now to  FIGS. 5 and 6B  there is seen a drawing showing expansion clip  400 / 400   a , which is used as described above to provide a pressured tensile grip on an instance of large tube outlet manifold  101   b  that is mounted to a surface using mounting clamp base  104  and mounting clamp top  105 / 105   a . In connection with the first embodiment of clamp top  105 , and as seen in  FIG. 3 , expansion clip  400  is secured to mounting clamp top  105  by pushing each instance of split round protrusions  403  into its mating instance of round receptacle  306  on mounting clamp top  105 . When split round protrusion  403  is fully inserted into round receptacle  306 , tension latching protrusion  404  extends just over the top of round receptacle  306 , and the outward tension of the individual legs of split round protrusion  403  causes tension latching protrusion  404  to expand outwards and clip over the exterior lip of the top of round receptacle  306 , thereby latching expansion clip  400  into place. In the alternative embodiment of expansion clip  404   a , as shown in  FIG. 6A , the clip is integrally formed in clamp top  105   a , thus obviating the need for connection apparatus for the clip, as described above. This is the preferred embodiment of the expansion clip as it is less expensive to manufacture in the injection molding process and does not include the split protrusion elements that make the clip vulnerable to damage and breaking. 
     With expansion clip  400 / 400   a  attached to mounting clamp top  105 / 105   a , when mounting clamp top  105 / 105   a  is secured to a mounted instance of mounting clamp base  104  (with an instance of large tube manifold clamped between them— FIGS. 5 and 6B ), mounting clamp top interface  401  of expansion clip  400 / 400   a  is urged against the interior of mounting clamp top  105 / 105   a , and large tube manifold interface  402  is urged against the exterior wall of large tube outlet manifold  101   b . Because the material from which expansion clip  400 / 400   a  is fabricated has a tensile property, mounting clamp top interface  401  and large tube manifold interface  402  tend to retain their original positions with respect to one another, thus creating a constant source of pressure against a large tube manifold to hold it in place. As can be seen in  FIG. 4 , in an undeformed configuration, mounting clamp top interface  401  is spaced apart from large tube manifold interface  402  but these elements are two curved portions joined by a bend  405 , formed of material sufficient resilient to allow decreases in the bend angle under the force of an expanding captured tube. This simple snap together design of mounting clamp base, mounting clamp top, and expansion clip makes the installation, maintenance, expansion, and removal of the system remarkably easy. 
     Temperature changes or wind conditions that cause large tube manifolds to change outside diameter (due to expansion, contraction or shape distortion) are automatically compensated for by the ability of expansion clip  400 / 400   a  to expand and contract to accommodate changes in the large tube caused by the environmental conditions. The result is that large tube manifolds are kept in a stable and secure position even under varying environmental conditions. 
     Referring next to  FIGS. 5 and 6B , there is shown how the large tube manifold (in this instance large tube outlet manifold  101   b , for purposes of illustration only) of the tube manifold assembly is secured into the mounting mechanism, which comprises mounting clamp base  104 , mounting clamp top  105 / 105   a  and expansion clip  400 / 400   a . In this drawing it can be seen that the large tube manifold is clamped between mounting clamp base  104  and mounting clamp top  105 / 105   a , with expansion clip  400 / 400   a , thereby providing pressure between mounting clamp top  105 / 105   a  and the exterior wall of large tube manifold. 
     In a first embodiment, expansion clip  400  is attached to mounting clamp top  105  by pushing tension latching protrusions  404  of split round protrusions  403  through, and latched over the upper lip of, round receptacles  306  for the split protrusions. In another embodiment, expansion clip  400   a  is integrally formed in mounting clamp top  105   a . Mounting clamp base  104  is secured to mounting clamp top  105  by inserting locking base clip  303  into, and pressure-latched to, base clip slot  305  of mounting clamp top  105   a.    
     In either configuration of the clamp top, the expansion clip ensures that pressure is exerted against large tube manifolds by large tube manifold interface  402  of expansion clip  400 / 400   a . This pressure is maintained because mounting clamp top interface  401  of expansion clip  400  is secured against the interior surfaces of mounting clamp top  105 / 105   a  and mounting clamp base  104  (those surfaces facing the large tube manifold). 
     From the foregoing, it will be appreciated that in its most essential aspect, the present invention is a modular thermal solar panel water heating system that includes a plurality of solar heating modules, each including a large tube inlet manifold, a large tube outlet manifold, a thin tube array disposed between and in fluid communication with each of the large tube inlet manifold and large tube outlet manifold, and fittings for coupling each solar heating module to an adjoining solar heating module. Water is provided to a first module in the plurality of modules, thus defining an inlet end of the panel array; water exits the plurality of modules through an outlet after passing through a succession of adjoined modules, and such fluid flow includes first passing into a large tube manifold and then through a thin tube array. The flow can be from one side only (i.e., the large tube inlet manifold side) across the thin tube array, into the large tube outlet manifolds, and then out the water outlet disposed in the final outlet manifold in the array. Alternatively, water can flow back and forth across the modules, first from the large tube inlet manifold across a thin tube array, into a first large tube outlet manifold, next into a second large tube outlet manifold, and across a thin tube array into a second large tube inlet manifold, and so on, all accomplished by configuring a series of plugs set between large tube manifolds in a staggered pattern. The fittings connecting the large tube manifolds are conventional coupling nuts, locking nuts, flanges, O-rings or gaskets, and the like. Variations from a purely linear panel array can be accommodated using angles and bends in the fittings with tube extensions that compensate for the different distances of the large tube inlet manifolds and large tube outlet manifolds from the same elements in the adjoining panel module. Most notably, the system includes a mounting system and mounting clamps that accommodate component expansion due to changing environmental conditions. 
     The foregoing description and the accompanying drawings show that an inexpensive solar panel array can be manufactured for easy installation onto a surface, and once installed, expansion is also easily achieved. The novel modular panel array system is physically stable in varying environmental conditions.