Solar Line Boiler Roof
A solar energy devices comprises a plurality of half cylinder troughs along a slanted roof of a static structure. The sun light entering the trough is reflected onto a secondary collector situated at a focus line of the primary collector. Light is directed onto a boiler tube contain a fluid to be used in an appropriate thermal cycle. Solar panels may be provided on surfaces along the secondary collector to power portions of the system. Braces can be provided to support the secondary collector over the primary collector. Reflectors may be provided to redirect light away from the braces onto the primary collector
1. Field of the Invention
The present invention relates to a method and apparatus for collecting solar power and a building or other static structure incorporating the same.
2. Description of the Prior Art
Interest in solar power continues to accelerate in the face of global warming, concern over the long term availability of petroleum and the pressures of rising energy prices. Tapping even a portion of available solar power has the potential to reduce reliance on petroleum and to hopefully reduce pressures on the national energy grid by distributing power generating sources more locally. Even cutting external energy demands by three percent would have a significant impact on energy demand and therefore on energy prices. And recently some cities have joined the effort by loaning the money to buy solar equipment to residents to encourage residents to buy solar.
One drawback to solar power, however, is that it tends to have low thermal efficiencies and the amount of area that a home would need to break even for the year on energy requirements is very high. What is needed is a way to make the most of the solar energy available to power a home while minimizing the costs of the power system to make solar power more energy efficient, more attractive and financially more effective.
None of the above inventions and patents, taken either singly or in combination, is seen to describe the instant invention as claimed.
SUMMARY OF THE INVENTIONAccording to a preferred embodiment of the present invention, two half cylinder troughs along a slanted roof of a building. The sun light entering the trough is reflected onto a secondary collector situated at a focus line of the primary collector. Light is directed onto a boiler tube contain a fluid to be used in an appropriate thermal cycle. Solar panels may be provided on surfaces along the secondary collector to power portions of the system. Braces can be provided to support the secondary collector over the primary collector. Reflectors may be provided to redirect light away from the braces onto the primary collector.
Accordingly, it is a principal object of a preferred embodiment of the invention to provide a highly efficient and cost effective solar system. It is another object of the invention to . . . .
It is a further object of the invention to . . . .
Still another object of the invention is to . . . .
It is an object of the invention to provide improved elements and arrangements thereof in an apparatus for the purposes described which is inexpensive, dependable and fully effective in accomplishing its intended purposes.
These and other objects of the present invention will be readily apparent upon review of the following detailed description of the invention and the accompanying drawings. These objects of the present invention are not exhaustive and are not to be construed as limiting the scope of the claimed invention. Further, it must be understood that no one embodiment of the present invention need include all of the aforementioned objects of the present invention. Rather, a given embodiment may include one or none of the aforementioned objects. Accordingly, these objects are not to be used to limit the scope of the claims of the present invention.
Similar reference characters denote corresponding features consistently throughout the attached drawings.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT(S)The present invention is to an improved method and apparatus for collecting and utilizing solar power, and a building incorporating the same. As shown in
The trough itself (“primary collector”) 120 is preferably semicircular in profile, basically a hollow cylinder cut substantially in half. The trough faces upward to allow sunlight in to shine off each face and focus onto a central focus line (F-F,
Optionally, as shown in
One advantage of the trough configuration compared to flat solar panels is that the troughs are somewhat self cleaning. Water from rain storms or from induced spray run through the troughs under force of gravity to clean the troughs of any debris. The troughs may optionally have a water source associated at an upper end or along the troughs to allow the troughs to be cleaned periodically.
As shown in
As mentioned above, the primary collector 140 acts to focus all of the light going through point F (“line F-F”) through the opening of a secondary collector, which then focuses the light onto boiler tube 150. The boiler tube contains water or preferably a more suitable refrigerant which is designed or chosen for the particular thermal cycle which the fluid undergoes, but for purposes of clarity and simplicity, the fluid of the system will be referred to in this application as water.
In a most preferred embodiment, solar cells are the side or sides of wing 148 near the mouth 142 of the secondary collector to catch stray solar rays. Light may reflect off the primary collector at a less than ideal angle due to surface imperfections, blockage caused by debris or for other reasons. Slight wings may be added to the lower end of the secondary collector near the mouth. Preferably the width of the wings does not substantially change the outer profile (i.e., does not cast additional shadow) of the secondary collector. The mouth 142 of the secondary collector is designed to be substantially larger than the focal point F to catch stray light. Light that is reflected just beyond the mouth that would normally be reflected out of the primary reflector back to the sky can be captured by these wings 148. Solar panels on the bottom and optionally on the top of the wing, catch sun light directed onto the wing. This additional energy may be utilized as needed, but is preferably used to power the functions of the solar collector itself, such as to rotate and/or align the secondary collector as will be discussed further below.
The top of secondary collector will generally point towards the sun. This will cause a shadow on the primary collector at a point below the mouth. The solar energy that would normally be wasted can be captured in part by providing solar panels 152 at the top of the secondary collector. Preferably, the total width (x′) of the top solar panels 152 is the same or nearly the same as the width (x″) of the body of the secondary collector to maximize the width of the solar panel without increasing the profile (“shadow”) of the secondary collector. Likewise, the wings 148 at the mouth of the collector are configured to have the same width as the secondary collector for the same reasons. It should be noted that the energy collected by the solar panel 152 will be directly related to the energy collected at the boiler tube 150, since the solar panels receive a fraction of the light that is also normally directed onto the boiler tube. This may be used in part to measure the light collected on or energy imparted to the boiler tube or for other purposes.
The secondary collector 140 is held in place over the primary collector 120 by a number of braces 160. While the primary and secondary collectors are preferably continuous along the length of the trough and have a substantially constant cross-section along the length, the braces 160 are only spaced intermittently along the trough. This is desirable to limit the shading effect of the braces on the primary collector. Any shade caused by the braces, which overly the primary collector, would reduce the amount of solar energy collected by the primary collector and thus needs to be minimized. The total number and size of the braces would depend on the weight and forces on the secondary collector, including forces from wind, rain, and snow.
These lateral braces 160 support the boiler tube and secondary collector preferably at both ends and in a series of spaced apart braces along the secondary collector. These braces preferably are insulated with a low conductivity material such as ceramics, especially where the braces connect to the boiler tube to minimize any heat losses from the boiler tube. As shown in
The secondary collector is preferably assembled as one continuous piece as shown in
Any method can be used to rotate the secondary collector about the boiler tube, including friction wheels between the secondary collector and the boiler tube, a stationary member on the boiler tube with a movable arm, etc. Any method that allows the secondary collector sections to move, preferably simultaneously or in a coordinated manner.
The secondary collector is preferably moved periodically to constantly point towards the sun throughout the day and or seasons, or more correctly, the mouth of the secondary collector is pointed directly away from the sun. In theory the trough is aligned parallel to the track of the sun and the collector will only have to be turned slightly each morning. However, this ability to rotate will also provide a correction mechanism for a misaligned trough or one that has shifted. Of course, one could also build an alignment adjustment mechanism into the trough connection to the static structure (“building”) to make slight alignment adjustments to the positioning of the primary collector trough during or after installation.
One preferred mechanism for tracking the sun involves placing a small hole 154 through the top solar collector 152 or at a break therein. By providing light sensors, photovoltaic sensor strips, charged capacitor devices or similar devices that can determine when the sun points at a position other than directly on line, the location of the light on the detectors around the target can be used to determine the current position of the secondary collector relative to the sun, such as by comparing measurements on various sensors. This information can be used to determine how to re-aim the secondary collector to maximize collection of the solar energy while minimizing the shadowing of the collector on the primary collector. Additionally or as an alternative, a daily estimation or annual historical data table can be used to pre-move the secondary collector a set amount for the day or for that particular day. Preferably energy collected and/or stored from the secondary solar cells such as those on the wings 148 and/or solar collector 152 of the secondary collector are used to rotate the secondary collector, but one skilled in the art would appreciate that other sources of power could be used. The energy derived from the solar panels 148, 152 can also be used to run pumps, such as for the fluid(s) in the boiler tube, or for other purposes.
The fluid in the boiler tube is thus heated to a maximum amount and can be circulated through an appropriate system to utilize the fluid to generate electricity, run air conditioning or heating systems, to heat water or for other purposes. By efficiently directing solar energy onto the boiler tube, solar energy can be used more efficiently than present systems. The exact usage of the fluid heated by the present system is elective and should not be used to limit the claims of the present application.
While this invention has been described as having a preferred design, it is understood that it is capable of further modifications, uses and/or adaptations of the invention following in general the principle of the invention and including such departures from the present disclosure as come within the known or customary practice in the art to which the invention pertains and as maybe applied to the central features hereinbefore set forth, and fall within the scope of the invention and the limits of the appended claims. It is therefore to be understood that the present invention is not limited to the sole embodiment described above, but encompasses any and all embodiments within the scope of the following claims.
Claims
1. A solar energy line boiler comprising:
- a trough having a substantially circular section and a light reflective interior surface;
- a boiler tube provided at a center of curvature of said trough;
- a reflector of constant interior reflecting cross-section for transposing light from a focus of said trough to the center of curvature where said boiler tube is provided, said reflector rotatably mounted to accommodate variations in the focus of said trough; and
- a pump for driving fluid through said boiler tube;
- wherein said trough is aligned such that an axis of rotation of said reflector is east to west such that fluid running within said boiler tube absorbs and transforms direct solar energy to an energy source for a static structure.
2. The solar energy line boiler according to claim 1, including: at least two troughs, each trough having a boiler tube and a reflector.
3. The solar energy line boiler according to claim 1, including multiple parallel boiler tubes, where a principle boiler tube is positioned at the center of curvature of said trough, and at least one secondary boiler tube is proximally positioned parallel thereto.
4. The solar energy line boiler according to claim 1, including a reflector motion and control photovoltaic system comprising: a photovoltaic panel mounted above said reflector; and a pair of photovoltaic sensor strips powered by the photovoltaic panel mounted to sides of said reflector; whereby the reflector may be positioned by comparing and balancing outputs of the photovoltaic sensor strips.
5. The solar energy line boiler according to claim 4, wherein the outputs of the sensor strips is further used to control said pump for driving fluid through the boiler tube.
6. The solar energy line boiler according to claim 5 wherein the pump provides a fluid pumping rate directly proportional to energy received by the photovoltaic system.
7. The solar energy line boiler according to claim 1 wherein the boiler tube is provided in a convection insulated light transparent housing.
8. The solar energy line boiler according to claim 1 including lateral braces that transverse the trough, boiler tube support for mounting the boiler tube to the braces, and notches provided in the reflector for the tube support.
9. The solar energy line boiler according to claim 8 including bearings for rotating the reflector, the reflector having planar reflective surfaces at each of the notches; tube unions for dismantling and servicing the boiler tube provided in the notches; and an eccentric fluid bypass provided between tube unions within each of the notches.
10. The solar energy line boiler according to claim 1, wherein the troughs form a roofing section for a static structure.
11. The solar energy line boiler according to claim 10, where said troughs are inclined along an east west axis, at an angle of inclination for the latitude of said static structure.
12. A static structure including a solar energy line boiler as part of its roof, the solar energy line boiler comprising:
- a trough having a substantially circular section and a light reflective interior surface;
- a boiler tube provided at a center of curvature of said trough;
- a reflector of constant interior reflecting cross-section for transposing light from a focus of said trough to the center of curvature where said boiler tube is provided, said reflector rotatably mounted to accommodate variations in the focus of said trough; and
- a pump for driving fluid through said boiler tube;
- wherein said trough is aligned such that an axis of rotation of said reflector is east to west such that fluid running within said boiler tube absorbs and transforms direct solar energy to an energy source for the static structure.
Type: Application
Filed: Nov 30, 2007
Publication Date: Jun 4, 2009
Inventor: Daniel D. De Lima (Norfolk, VA)
Application Number: 11/948,029
International Classification: F24J 2/38 (20060101); F24J 2/04 (20060101); F24J 2/46 (20060101);