WATER HEATING

TECHNICAL FIELD

[0001] The present invention generally relates to the field of the use of solar heating. More particularly, the present invention relates to the use of water solar heating having thermosiphonic circulation.

BACKGROUND ART

[0002] Water heated by the sun is used in various ways. While perhaps best known in a residential setting to provide domestic hot water. In order to heat water using solar energy, a collector, often fastened to a roof or a wall facing the sun, heats water that is flowing through it. The collector could be made of a simple glass-topped insulated box with a flat solar absorber made of sheet metal, attached to heat exchanger pipes.

[0003] Heat is stored in a hot water storage tank. The volume of this tank needs to be larger with solar heating systems in order to allow for bad weather. The water tanks are heavily insulated and are often roof-mounted. All such tanks share the same problems as artificially heated tanks including limestone deposit and corrosion, and suffer similar reductions in overall efficiency unless scrupulously maintained.

[0004] One approach to simplify the installation of solar water heating systems is the use of Integral Collector Storage (ICS). Such a solar system is comprised of a housing, which includes a water tank. The water within the water tank is directly heated by the sun, as described in US patent publication 2008/0308092.

[0005] US patent application US2011/030676 discloses another configuration of ICS. In this case, the upper part of the tank is built to increase the area of the heated surface of the tank. The bottom and the sides of the tank are insulated from the environment, albeit its top part is open to the environment.

[0006] What is needed is a simple to install, simple to manufacture, efficient, maintenance free solar water heating system.

SUMMARY OF INVENTION

[0007] A unified integrated storage-collector solar water heating system is disclosed. The storage (water tank) and the heat collector reside in the same flat rectangular box shaped housing, uni- body. The water tank is comprised of plurality of tank water pipes placed next to each other. At the edges of the tank water pipes there are bottom cap cover and top cap cover that enable water flow between the water tank pipes. The heat collector is comprised of plurality of water pipes placed next to each other. The pipes can be close to each other or spaced apart. At the edges of the collector water pipes there are bottom and top cap covers that enable water flow between the water collector pipes. Note that the cross-section of the tank water pipes is much larger than that of the heat collector water pipes. The heat collector water pipes are directly exposed to the sun. There are top connecting pipes and bottom connecting pipes. The top connecting pipes enable water flow between the top heat collector cap cover and the top water tank cap cover. The bottom connecting pipes enable water flow between the bottom heat collector cap cover and the bottom water tank cap cover. The water circulates between the water tank and the heat collector by thermosiphon. The system is comprised of three manufactured parts, two covers and the main body. Note that the cross-section of the pipes can have different shapes. They could be of rectangular cross-section, elliptical cross-section, hexagonal cross-section etc.

[0008] An objective of the invention is to reduce the manufacturing cost, by designing the main body in such a way that it can be produced by extrusion.

[0009] It is another objective of the invention, to easily modify the capacity of a manufactured unit. This can be easily accomplished by cutting the length of the main body, which comes out from the extrusion machine. BRIEF DESCRIPTION OF DRAWINGS

[0010] Fig. 1 presents perspective view of the structure of a basic unit according to the disclosed invention.

[0011] Fig. 2 presents a perspective view of a system comprised of three basic units.

[0012] Fig. 3 presents a perspective view of an embodiment of the water tanks and heat collector.

[0013] Fig. 4 presents a perspective view of another embodiment of the water tanks and heat collector.

[0014] Fig. 5 presents a perspective view of a glazed embodiment of the water tanks and heat collector

DETAILED DESCRIPTION

[0015] The invention will be described more fully hereinafter, with reference to the accompanying drawings, in which certain possible embodiments of the invention are shown. The invention may, however, be embodied in many different forms and should not be construed as limited to the embodiments set forth herein; rather these embodiments are provided so that the disclosure will be thorough and complete, and will fully convey the scope of the invention to those skilled in the art.

[0016] In the disclosed invention all components of the water heating system is contained in one unit, which we call uni-body implementation.

[0017] A perspective view of the structure of a basic unit is presented in Fig. 1. This view is used to explain the principle of operation of the solar water heating system, the subject of the disclosed invention. The basic unit 100 is comprised of a water tank 110, shaped as water pipe having square cross-section, heat collector 130, comprised of plurality of heat collector water pipes 132 having square cross-section. Insulation layer 120 is separating the water tank 110 and the heat collector 130.

[0018] The water tank 110 has a bottom cap cover 112 and top cap cover 114. The heat collector

130 has a bottom cap cover 134 and top cap cover 136. The heat collector 130 is coupled to the water tank 110 via bottom connecting pipe 122 located in the bottom cap cover of the water tank cap cover 112 and the heat collector cap cover 134, that allows cold water to flow from the water tank 110 to the heat collector 130. Another connecting pipe, located in the top cap cover of the tank 114 and the heat collector cap cover 136, allows hot water to flow from the heat collector 130 to the water tank 110. Note that the water in the heat collector water pipes 132 flows in parallel. The water entering the heat collector water pipes shown by arrow 150 is cold. Because of sun radiation, the water in these collector water pipes is heated, and as a result, it moves upward as shown by arrows 152. Thermosiphon causes circulation of the water between the heat collector water pipes 132 and the water tank 110. Cold water 140 enters the unit at the bottom cap cover of the tank 112 and hot water are coming out of the water tank 150 from its top cap cover 114.

[0019] It is important to note that the heat collector water pipes can have any cross-section shape. This is also true also for the water tank pipes. As an example, the heat collector water pipes can have circular cross-section, and the water tank pipes can have rectangular cross-section. The heat collector water pipes and the water tank can be made of different materials, such as metal, plastic, polymers, or combination of these materials.

[0020] Perspective view of a system comprised of three basic units, as described above, is shown in fig. 2. When plurality of units are combined, the bottom and top cap covers of both, the heat collectors and the water tanks are unified, so that water can flow between water tanks and between heat collectors. In fig. 2, three water tanks 210 are attached to each other. The heat collector 230 contains many heat collector pipes in parallel. Between the water tanks 210 and the heat collector 230 there is an insulation layer 220. Tanks bottom cap cover 212 and top cap cover 214 enable water flow between the water tanks. Heat collector bottom cap cover 232 and top cap cover 234 enable water flow between all heat collector water pipes. Cold water enter the unit via pipe 240 on the bottom cap cover of the tanks 212, and hot water are coming out from pipe 250 connected to the top cap cover of the tanks 214. Water between the tank and the heat collector flows via plurality of water connecting pipes, connecting the top cap cover of the water tanks to the top cap cover of the heat collector, and the bottom cap cover of the water tanks to the bottom cap cover of the heat collector 222.

[0021] Fig 3 presents a perspective view of an embodiment of the water tanks and heat collector without the bottom and top cap covers. The water tank is comprised of plurality of pipes 310 attached to each other. Typical external diameter of the tank pipes is 7.5 cm and the internal diameter is 6.9 cm. The heat collector is comprise of plurality of heat collector pipes 332 attached to each other. The upper face of the heat collector pipes form a plain that constitutes part of the housing top cover 300 of the unit. It is important to note that in the shown embodiment there is no glazing material on the top surface of the heat collector, and the heat collector pipes are directly exposed to the sun. In another embodiment, a glazing material can be installed above the collector pipes. Being made of dark material the effectively absorb the heat from the sun. Insulation 320 surrounds the tank pipes.

[0022] If the length of the water tank pipes is 200 cm, and 15 water tank pipes are used, then the volume of water stored in the tanks is 112 litre. The external diameter of the heat collector pipes is 2.5 cm and the internal diameter is 2.2 cm. Thus, there are 45 heat collector pipes. The volume of water stored in the collector is 34 litre. Including insulation layer of 2.5 cm surrounding the tank, a unit 200 in length, 117 cm width and 15 cm thick can store 146 litre of water. It is clear that different dimensions can be selected to suit the requirements.

[0023] The structure presented in fig 3 can be made of various materials. However, an important advantage of the structure shown in the figure is that it is easy to manufacture. The structure shown in fig 3 can be easily manufactured by extrusion process.

[0024] Another embodiment is presented in fig 4 and fig 5. In this embodiment, the heat collector is constructed of pipes 410 which are not touching one another, but there is a space between close pipes. The tank pipes 430 are surrounded by insulation material 450. In this embodiment there is just one bottom cap cover 420 and one top cap cover 422. These covers enable water flow between heat collector pipes, between water tank pipes as well between heat collector pipes and water tank pipes. The embodiment presented in fig 5 has additional glazing material 510 that covers the heat collector pipes.

[0025] What has been described above are just a few possible embodiments of the disclosed invention. It is of course, not possible to describe every conceivable combination of components and/or methodologies, but one of ordinary skill in the art may recognize that many further combinations and permutations are possible. Accordingly, the invention is intended to embrace all such alterations, modifications, and variations that fall within the spirit and scope of the invention.