Stoves and furnaces – Solar heat collector – With concentrating lens
Reexamination Certificate
1997-06-11
2001-10-16
Yeung, James C. (Department: 3743)
Stoves and furnaces
Solar heat collector
With concentrating lens
C126S683000, C126S685000, C126S699000
Reexamination Certificate
active
06302100
ABSTRACT:
BACKGROUND OF THE INVENTION
The design effort leading to the subject invention was motivated by the perceived need for solar assisted heating and cooling systems. The first part of this effort resulted in the development of a Vapor Jet Compressor Pump (VJCP), disclosed in U.S. Pat. No. 5,228,310 (which patent is incorporated herein by reference), which had multiple functions, one of which was to serve as a heat pump motivated by solar produced vapor. In this/present application, the VJCP is motivated by the high temperature vapor produced by the collector's receiver. The heat pumping attribute of the VJCP is then used to pump heat from the collector that normally escapes to the outside environment. The temperature inside the collector resulting from heat losses from the high temperature receiver and the absorption of unfocused rays of light is thus reduced to about 50° F. The consequent lowered temperature difference between the cover and the outside environment reduces the energy loss from the collector. For instance, if the outside temperature is 50° F., the loss to the outside would be zero if reflection back to the outside is neglected.
The energy in the vapor supplying the VJCP, plus the pumped heat, is discharged by the VJCP into the space to be heated at temperatures needed for its economical transfer to room air. As a result of this utilization of the heat normally escaping from a collector, the efficiency of the collector approaches 100%.
In the cooling mode of operation, the VJCP pumps heat from the room to be cooled instead of the collector. Calculations indicate that a 250 ft.
2
collector—VJCP combination will produce about 17 ton-hr. of cooling per day in New York state during the cooling season.
SUMMARY OF INVENTION
A novel fixed-position solar collector is disclosed which accepts both diffused and direct solar radiation from all directions the same as a flat-plate collector but, in addition, focuses and concentrates both forms to produce significantly higher temperatures and efficiencies than achieved by conventional collectors.
This performance is partly due to the design of the cover of the collector which preferably consists of striated plastic material and clear glass. The striated material is arranged horizontally across the width of the collector to form small, shallow prismatic slabs over the entire surface. The index of refraction of the slabs alternates between two values so that each horizontal slab is bounded by the alternate index of refraction. Refraction and total internal reflection of the light passing through this arrangement causes a reduction in the divergence of the incident radiation with respect to the normal to the surface of the prismatic slabs.
Additional striated layers are preferably bonded to the first layer to further reduce the divergence. The theoretical divergence between rays exiting from the bottom of the cover is less than one degree. The nearly parallel rays preferably are then focused by optical or fiber optic means or a combination of optical and fiber optic means onto a receiver to form a focal line along the length of the receiver, extending across the collector's width, to produce temperatures and efficiencies significantly greater than can be obtained with conventional flat-plate collectors.
Calculations indicate that the cover, theoretically, can be a small fraction of an inch thick. It is estimated that practical consideration of fabrication tolerances and material homogeneity will cause the cover to be about ½ inch thick.
The focal line alternatively can be reduced to a square area by adding a second array of prismatic slab layers to the first to reduce the azimuthal rays' divergence from the normal to square the concentration factor. These higher concentrations permit the use of fiber optic transmission of energy to locations remote from the collector, and also the use of photovoltaic or thermoelectric direct conversion to produce about 16 kilowatt-hours per day of electric energy from a 250 ft.
2
collector simultaneously with the production of thermal energy for space heating or cooling. Calculations indicate that light falling on one square foot of the fiber optic acceptor surface can be introduced into a fiber optic cable less than 0.0182 inches in diameter. In the thermoelectric application, the heat rejected at the thermoelectric cold junctions is at temperatures sufficient for heating or cooling space, hence the electricity is a bonus as a result of the availability of additional energy at high temperatures. Electricity produced by the renewable, non-polluting solar energy source, instead of by the combustion of fossil fuel, eliminates an objection to the use of electric motor vehicles. The generated electrical power also can be used for system fans and circulating pumps to make the system completely self-energized for use in remote areas.
The cover of the solar collector of this invention preferably can accept light rays in an angle of incidence range of about 0-80 degrees to the normal of its surface. The rays are emitted from the bottom surface in a rectangular beam having a total divergence of less than 4 degrees with respect to the short side of the rectangle. The substitution of this cover material for the lens on existing motor vehicle headlights is shown to reduce or essentially eliminate the hazardous temporary blinding caused by approaching vehicles during night driving.
OBJECTIVES
The objectives of the inventions described in this specification include:
1. To focus the direct solar radiation from nearly all solar altitudes and azimuths with a fixed positioned solar collector.
2. To focus most of the diffused radiation from all directions that pass through an imaginary hemispheric envelope over the collector.
3. To provide solar energy at temperatures greater than 1000° F. at an outside temperature as low as 32° F.
4. To provide direct conversion of solar energy to electricity.
5. To provide thermal energy for heating and cooling as a by-product of the direct conversion process.
6. To provide a solar-assisted heating system.
7. To provide a solar-assisted cooling system.
8. To provide for the transmission of solar energy through use of fiber optics techniques.
9. To increase fiber optic acceptance angles compared to existing acceptors.
10. To provide steam for operating a vapor-jet heat pump.
11. To use the steam-jet heat pump to pump low temperature heat normally escaping from conventional collectors in the winter to higher temperatures for space heating.
12. To use the heat pump to lower the temperature in the collector to reduce the thermal loss to the outside.
13. To produce overall collector efficiencies greater than 90% in an outside temperature of 32° F. as a consequence of pumping heat from the lower temperature, compared to conventional flat-plate collectors producing temperatures less than 150° F. at efficiencies of 35%.
14. To use the focused heat collected at high temperatures to supply the vapor-jet heat pump to pump the low temperature heat normally escaping from the collector so that the combined heat flow is useful for heating space at more than 90% collector efficiency.
15. To provide heat energy for supplying the vapor-jet pump for cooling space in the summer.
16. To provide a unique design that minimizes the increase in entropy during the energy exchange from solar to thermal energy.
17. To reduce the dependency between collector efficiency and its positioning to increase architectural options.
18. To provide a self energized heating and cooling system completely independent of outside energy sources other than solar.
19: For the above objectives that relate to the collection of solar radiation, to achieve such objectives using a non-moving collector fixed in one position.
20. To produce a light beam essentially invisible in all regions outside the boundaries of the sharply defined beam of low divergence.
21. To achieve these objectives using optical materials having indices of refraction of ordinary plastic and glass.
REFERENCES:
patent: 593045 (1897-11-0
Klarquist & Sparkman, LLP
Vandenberg Leonard
Yeung James C.
LandOfFree
System for collimating and concentrating direct and diffused... does not yet have a rating. At this time, there are no reviews or comments for this patent.
If you have personal experience with System for collimating and concentrating direct and diffused..., we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and System for collimating and concentrating direct and diffused... will most certainly appreciate the feedback.
Profile ID: LFUS-PAI-O-2574457