CA1071049A - Solar collector apparatus - Google Patents
Solar collector apparatusInfo
- Publication number
- CA1071049A CA1071049A CA282,608A CA282608A CA1071049A CA 1071049 A CA1071049 A CA 1071049A CA 282608 A CA282608 A CA 282608A CA 1071049 A CA1071049 A CA 1071049A
- Authority
- CA
- Canada
- Prior art keywords
- jacket
- glass
- tubing
- solar energy
- tube
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Expired
Links
Classifications
-
- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F24—HEATING; RANGES; VENTILATING
- F24S—SOLAR HEAT COLLECTORS; SOLAR HEAT SYSTEMS
- F24S10/00—Solar heat collectors using working fluids
- F24S10/40—Solar heat collectors using working fluids in absorbing elements surrounded by transparent enclosures, e.g. evacuated solar collectors
- F24S10/45—Solar heat collectors using working fluids in absorbing elements surrounded by transparent enclosures, e.g. evacuated solar collectors the enclosure being cylindrical
-
- Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
- Y02—TECHNOLOGIES OR APPLICATIONS FOR MITIGATION OR ADAPTATION AGAINST CLIMATE CHANGE
- Y02E—REDUCTION OF GREENHOUSE GAS [GHG] EMISSIONS, RELATED TO ENERGY GENERATION, TRANSMISSION OR DISTRIBUTION
- Y02E10/00—Energy generation through renewable energy sources
- Y02E10/40—Solar thermal energy, e.g. solar towers
- Y02E10/44—Heat exchange systems
Landscapes
- Engineering & Computer Science (AREA)
- Physics & Mathematics (AREA)
- Life Sciences & Earth Sciences (AREA)
- Sustainable Development (AREA)
- Sustainable Energy (AREA)
- Thermal Sciences (AREA)
- Chemical & Material Sciences (AREA)
- Combustion & Propulsion (AREA)
- Mechanical Engineering (AREA)
- General Engineering & Computer Science (AREA)
- Optical Elements Other Than Lenses (AREA)
Abstract
ABSTRACT OF THE DISCLOSURE
Solar collector apparatus comprising a panel of series connected all glass solar tubes, each tube having an outer evacuated glass cylindrical jacket with a half circular concave cylindrical reflector on its inner surface, blackened heat absorption glass tubing within the jacket secured by glass connection support means to the jacket in an offset position to lie in the focal plans of the reflector, and circulating fluid storing the energy within the heat absorption tubes.
Solar collector apparatus comprising a panel of series connected all glass solar tubes, each tube having an outer evacuated glass cylindrical jacket with a half circular concave cylindrical reflector on its inner surface, blackened heat absorption glass tubing within the jacket secured by glass connection support means to the jacket in an offset position to lie in the focal plans of the reflector, and circulating fluid storing the energy within the heat absorption tubes.
Description
1~716~49 Solar energy collecting device~ are of two type8, ~hose with movable part:s which track the sun and flat plate collectors. The latter have presented a problem in that it was hitherto neces~ary for their co~ponents to be indi~
vidually designed and crafted, adding appreciably eo the cost. Present dey tec~mology in the glas~ industry would now allow for mass production.
The pri~e problem a~sociated with solar collector3 has been the ef-ficient retention of heRt energy or stated conversely the prevention cf he~t 108s. ~eat 1088 oc~urs in three ways, by convection, by conduct~on and by radiation. The first means of heat transference, convection, can be eliminated by evacuating the ambient surrounding the heat absorption means. Conduction can be appreciably reduced by eliminating the use of good heat conductors such as m2tals, and the interfacing of materialæ with different level~ of heat contuctivity.
The refocusing of scattered radiation ~y the concave ~ir~ored sur-face of the ~acket and by the one way reflector coating on the remainder of the inner ourface of the ~acket, 80 that it is directed on the blackened heat absorption neans, further aid~ in reducing heat lc88. The evacuated smbient reduces deterioratioo of the mirror, and the efficiency of the blackening mæans increase heat absorption.
It io the primary ob~ect of the present invention to pro~ide a collector which i8 capable of ~a~ production, relatively low in cost, durable and which generates the st hea~ for the available solar radiation.
Partlcular care has been given to desi8n a solar collector suitable for u~e in clouty and cool climes with a ~lnimum of heat loas. A practical collector ~hould act as a one way hoat trap, energy ~hould flow uni-directionally into the sy~tem and not radiate back out. The present collector has been dèsi8ned wholly of borosilicate glas~ pre~enting no interfaces of differing materials with different ratcs of heat conductivity and its attendent heat 10~8. The all gl~88 collector 1~ capable of being mass produced and has hiKh evacuation and insulating capabillties which will withstand long periods of cold and cloudy weather.
There is an ancillary benefit derivet from the u~e of an all glass collector, namely it solves one of the ~Dst urgent of collector problems, . : . - ~
.
~C)71049 corrosion. Corrosion has been a formidable problem in this art both from exposure to the elements which requires elaborate shielding, and from the circulation of the fluids within the collecting tubes. Corrosion has necessitated premature and costly replacement of parts in the collectors.
The present evacuated tubular solar thermal collector has many unique features among which are that it is constructed entirely of glass with the exception of the aluminized reflective ~ ~ -surface. This construction eliminates heat losses attendant with metal-fluid interfaces. Additionally, glass to metal seals are not as strong as glass seals. An all glass construction alleviates expansion problems in a system in which the inner and outer tubes will be at varying tempertures in a high vacuum.
The use of a high vacuum virtually eliminates conven- -tion and the use of glass minimizes conduction. In effect, the operatlng efficiency of the collector is independent of the outslde temperature, which is particularly important in cold climate~.
Broadly speaking, therefore, and in summary of the abovel the present invention may be defined as a glass solar energy collector tube comprising an outer cylindrical evacuated ~acket having a reflective coating on its inner surface extending around approximately half the circumference of the ~acket and constituting a concave mirror, inner glass absorption tubing circulating heat storing fluid in and out of the jacket, the tubing lying in the focal plane of the concave reflecting coating, glass connecting means between the outer jacket and the inner tubing to support and position the tubing within the jacket, and blackening means associated with the inner tubing to increase 3D the absorption of heat energy, the ~acket comprising a main elongated cylindrical body portion having a central longitudinal ; axis, a sealed necked entry portion coaxial with tbe longitudinal axis, and a dimini~hed rounded end, and the reflecting coating extending the length of the main elongated cylindrical body portion of tlle jacket, the absorption tubing for circ-llating the heat storing fluid entering through the sealed entry of the jacket and being offset in the main body portion, ~xtending nearly the length of the nlaln body portioll of the jacket, and doubling over upon itself defining parallel ingress and egress legs, one of the legs lying along the principal axis of the concave mirror and the other leg of the inner tubing paralleling the one leg and being disposed between the one leg and the longitudinal axis of the body portion of the jacket for capturing scattered radiation, the one leg being spaced from the reflecting coating, and the legs being similarly offset to exit the sealed necked entry of the jacket.
The present invention will be described in greater detail and with reference to the drawing6 wherein:
- Figure 1 is a plan view of a solar collecting panel mounted on a support structure.
Figure 2 is a plan view of an individual collector tube with the process tube for evacuating the colleotor still in place.
Figure 3 i9 a cross-sectional view taken on line 3-3 of Figure 2.
Figure 4 is a cross-sectional view taken on line 4-4 of Figure 3 through the neck of the collector tube ~acket.
Figure 5 is a cross-sectional view taken through the main cylindrical portion of the collector tube ~acket.
Figure 6, appearing on the same sheet as Figure 1, is the top end view of the lntake and outtake portions of the fluid circulating tube system.
Referring now to the drawings in detail wherein like reference characters indicate like parts throughout the several figures, the reference numeral 10 indicates generally a solar collector panel which consists of a number of collecting tubes - 2a -each having an outer evacuated glass jacket 8, which encases heat absorption fluid circulating tubes 12 which are serially connected in the panel, see Figure 1. A process tube 14 used for evacuating the glass jacket, is shown in Figures 2 and 3, before it is burned off when ' " ':
' ' -,' ~.
.
~ ' ~: :
- :
- .~. .
~ .
' ` ' "' ' : :
' . w~
~ 2b --'`' ~.'' ;:
: . - . ~ .. . .... . .
1~7~49 the neck 16 of the ~acket i8 se~let after the vacuu~ i8 achievet. The vacuum 18 of a high order, (4 x 10 6 Torr.) which virtually eliminates the convection mechanism of heat 1088. The main body of the gla3s ~acket i~
a C~*i~ rS
cylindrical in configuration and about one hundred and twelve ~ in len~Sth, the neck of the ~acket i8 additionally seventy-five millimeters long and the opposite diminished rounded end 20 i8 fifty millimeters in length.
The absorption tube 12 wh1ch has a diameter of nineteen millimeters as com-pared to a hundred ~illi~eters of the cylintrical ~acket enters the neck of the cylinder and i8 offset to extend the length of the main portion of the cylinder in proxlmity to and parallel with the wall of the cylinder. The tube 12 is doublet over upon itself short of the rounded end 20 to lie as clo~e to itself as po~sible without contact. The egress tube parallel~ the ingress tube for the length of the cylinter and i8 similarly offset to exit the neck of the ~acket. In Figures 1 and 6 insulating sleeves are ~hown encasing the con-necting portions of the tubes 12. The doublet over humped turnaround bight B f tube 12 is ~hown in Figure ~ and lndicated at 13. A curved gla~s support and positionlng means 24 has three arched portions connected together with the free ends of each secured one to the humped turn of the circulatlng tubing, and the other two, designated 26, to opposed walls lô of the diminished end 20. ~11 members described, the ~acket, heat absorption tubing and support ~nd po~itioning me~bers are made of borosilicate glass. There are no inter-facos of dissimilar materials to di~sipate the heat.
There are three wsys to blacken the heat absorption tublng. The cir-culation fluid may be blackened by means of dyes or colloidal suspensions such a~ Lo~pblack, graphite or charcoal in a water base. Antl-free~e and other agent~ may be added to the fluid. A black coating on either the outer or inner surface of tube 12 would provide another means of achlevlng heat absorption.
An aluminum coatlng i~ placed upon the inner sur~ace of the cylin-drical ~acket extendlng the length of the maln portion thereof and having a lateral extont of half the clrcu~ference of the ~acket. Thi~ coated 3urface constitute~ a concava cylintrical d rror for the reflection of entering light rays to focu~ them on the absorption tubi~g. The absorption tubing i~ placod along tho princlpal a~is of the concave reflecting mirror at the ~.~7~ 4~
focus of the light reflectet from the mirror. Parallel rays of light enter-ing the cylindrical tubing will be slightly converged by the convex surface o the ~acket and the focusing of the reflected light fron the concave mirror will be closer to the mirror than the principal focu~ and will extend the length of the mirror. Some of the entering rays of light will strike the inner ab~orption tubes directly and be absorbed, but others will be directet to the mirror and refocused on the lnner absorption tubing. Some of the radiation will scatter snt exit the glass cylinder. The doubllng of the absorption tubing will extend it a dist~nce of over for~y ~illimeters deep into the ~acket along the primary axi8 of the concave mirror. Thi~ tepth will allow the upper portion to capture scattered radlation. By necking the cylinder, the absorption tubing will retard 3cattered radiation and serve as additional insulation in that area. To further minimize the 10~8 of scat-tered radiation, a one war light transmitting coating, known in the glass art, may be applied to the inner surface of the ~acket. Such one wny transparent coating would allow light to pass unl-directionally into ths cylinder but not out. Those coatings may act a8 a second reflecting surface bouncing back ~cattered radlstlon and retaining it within the collector tube.
- : - - : , . .
- - - . ,, , . . . - : .
, . . - : - ~ ~,
vidually designed and crafted, adding appreciably eo the cost. Present dey tec~mology in the glas~ industry would now allow for mass production.
The pri~e problem a~sociated with solar collector3 has been the ef-ficient retention of heRt energy or stated conversely the prevention cf he~t 108s. ~eat 1088 oc~urs in three ways, by convection, by conduct~on and by radiation. The first means of heat transference, convection, can be eliminated by evacuating the ambient surrounding the heat absorption means. Conduction can be appreciably reduced by eliminating the use of good heat conductors such as m2tals, and the interfacing of materialæ with different level~ of heat contuctivity.
The refocusing of scattered radiation ~y the concave ~ir~ored sur-face of the ~acket and by the one way reflector coating on the remainder of the inner ourface of the ~acket, 80 that it is directed on the blackened heat absorption neans, further aid~ in reducing heat lc88. The evacuated smbient reduces deterioratioo of the mirror, and the efficiency of the blackening mæans increase heat absorption.
It io the primary ob~ect of the present invention to pro~ide a collector which i8 capable of ~a~ production, relatively low in cost, durable and which generates the st hea~ for the available solar radiation.
Partlcular care has been given to desi8n a solar collector suitable for u~e in clouty and cool climes with a ~lnimum of heat loas. A practical collector ~hould act as a one way hoat trap, energy ~hould flow uni-directionally into the sy~tem and not radiate back out. The present collector has been dèsi8ned wholly of borosilicate glas~ pre~enting no interfaces of differing materials with different ratcs of heat conductivity and its attendent heat 10~8. The all gl~88 collector 1~ capable of being mass produced and has hiKh evacuation and insulating capabillties which will withstand long periods of cold and cloudy weather.
There is an ancillary benefit derivet from the u~e of an all glass collector, namely it solves one of the ~Dst urgent of collector problems, . : . - ~
.
~C)71049 corrosion. Corrosion has been a formidable problem in this art both from exposure to the elements which requires elaborate shielding, and from the circulation of the fluids within the collecting tubes. Corrosion has necessitated premature and costly replacement of parts in the collectors.
The present evacuated tubular solar thermal collector has many unique features among which are that it is constructed entirely of glass with the exception of the aluminized reflective ~ ~ -surface. This construction eliminates heat losses attendant with metal-fluid interfaces. Additionally, glass to metal seals are not as strong as glass seals. An all glass construction alleviates expansion problems in a system in which the inner and outer tubes will be at varying tempertures in a high vacuum.
The use of a high vacuum virtually eliminates conven- -tion and the use of glass minimizes conduction. In effect, the operatlng efficiency of the collector is independent of the outslde temperature, which is particularly important in cold climate~.
Broadly speaking, therefore, and in summary of the abovel the present invention may be defined as a glass solar energy collector tube comprising an outer cylindrical evacuated ~acket having a reflective coating on its inner surface extending around approximately half the circumference of the ~acket and constituting a concave mirror, inner glass absorption tubing circulating heat storing fluid in and out of the jacket, the tubing lying in the focal plane of the concave reflecting coating, glass connecting means between the outer jacket and the inner tubing to support and position the tubing within the jacket, and blackening means associated with the inner tubing to increase 3D the absorption of heat energy, the ~acket comprising a main elongated cylindrical body portion having a central longitudinal ; axis, a sealed necked entry portion coaxial with tbe longitudinal axis, and a dimini~hed rounded end, and the reflecting coating extending the length of the main elongated cylindrical body portion of tlle jacket, the absorption tubing for circ-llating the heat storing fluid entering through the sealed entry of the jacket and being offset in the main body portion, ~xtending nearly the length of the nlaln body portioll of the jacket, and doubling over upon itself defining parallel ingress and egress legs, one of the legs lying along the principal axis of the concave mirror and the other leg of the inner tubing paralleling the one leg and being disposed between the one leg and the longitudinal axis of the body portion of the jacket for capturing scattered radiation, the one leg being spaced from the reflecting coating, and the legs being similarly offset to exit the sealed necked entry of the jacket.
The present invention will be described in greater detail and with reference to the drawing6 wherein:
- Figure 1 is a plan view of a solar collecting panel mounted on a support structure.
Figure 2 is a plan view of an individual collector tube with the process tube for evacuating the colleotor still in place.
Figure 3 i9 a cross-sectional view taken on line 3-3 of Figure 2.
Figure 4 is a cross-sectional view taken on line 4-4 of Figure 3 through the neck of the collector tube ~acket.
Figure 5 is a cross-sectional view taken through the main cylindrical portion of the collector tube ~acket.
Figure 6, appearing on the same sheet as Figure 1, is the top end view of the lntake and outtake portions of the fluid circulating tube system.
Referring now to the drawings in detail wherein like reference characters indicate like parts throughout the several figures, the reference numeral 10 indicates generally a solar collector panel which consists of a number of collecting tubes - 2a -each having an outer evacuated glass jacket 8, which encases heat absorption fluid circulating tubes 12 which are serially connected in the panel, see Figure 1. A process tube 14 used for evacuating the glass jacket, is shown in Figures 2 and 3, before it is burned off when ' " ':
' ' -,' ~.
.
~ ' ~: :
- :
- .~. .
~ .
' ` ' "' ' : :
' . w~
~ 2b --'`' ~.'' ;:
: . - . ~ .. . .... . .
1~7~49 the neck 16 of the ~acket i8 se~let after the vacuu~ i8 achievet. The vacuum 18 of a high order, (4 x 10 6 Torr.) which virtually eliminates the convection mechanism of heat 1088. The main body of the gla3s ~acket i~
a C~*i~ rS
cylindrical in configuration and about one hundred and twelve ~ in len~Sth, the neck of the ~acket i8 additionally seventy-five millimeters long and the opposite diminished rounded end 20 i8 fifty millimeters in length.
The absorption tube 12 wh1ch has a diameter of nineteen millimeters as com-pared to a hundred ~illi~eters of the cylintrical ~acket enters the neck of the cylinder and i8 offset to extend the length of the main portion of the cylinder in proxlmity to and parallel with the wall of the cylinder. The tube 12 is doublet over upon itself short of the rounded end 20 to lie as clo~e to itself as po~sible without contact. The egress tube parallel~ the ingress tube for the length of the cylinter and i8 similarly offset to exit the neck of the ~acket. In Figures 1 and 6 insulating sleeves are ~hown encasing the con-necting portions of the tubes 12. The doublet over humped turnaround bight B f tube 12 is ~hown in Figure ~ and lndicated at 13. A curved gla~s support and positionlng means 24 has three arched portions connected together with the free ends of each secured one to the humped turn of the circulatlng tubing, and the other two, designated 26, to opposed walls lô of the diminished end 20. ~11 members described, the ~acket, heat absorption tubing and support ~nd po~itioning me~bers are made of borosilicate glass. There are no inter-facos of dissimilar materials to di~sipate the heat.
There are three wsys to blacken the heat absorption tublng. The cir-culation fluid may be blackened by means of dyes or colloidal suspensions such a~ Lo~pblack, graphite or charcoal in a water base. Antl-free~e and other agent~ may be added to the fluid. A black coating on either the outer or inner surface of tube 12 would provide another means of achlevlng heat absorption.
An aluminum coatlng i~ placed upon the inner sur~ace of the cylin-drical ~acket extendlng the length of the maln portion thereof and having a lateral extont of half the clrcu~ference of the ~acket. Thi~ coated 3urface constitute~ a concava cylintrical d rror for the reflection of entering light rays to focu~ them on the absorption tubi~g. The absorption tubing i~ placod along tho princlpal a~is of the concave reflecting mirror at the ~.~7~ 4~
focus of the light reflectet from the mirror. Parallel rays of light enter-ing the cylindrical tubing will be slightly converged by the convex surface o the ~acket and the focusing of the reflected light fron the concave mirror will be closer to the mirror than the principal focu~ and will extend the length of the mirror. Some of the entering rays of light will strike the inner ab~orption tubes directly and be absorbed, but others will be directet to the mirror and refocused on the lnner absorption tubing. Some of the radiation will scatter snt exit the glass cylinder. The doubllng of the absorption tubing will extend it a dist~nce of over for~y ~illimeters deep into the ~acket along the primary axi8 of the concave mirror. Thi~ tepth will allow the upper portion to capture scattered radlation. By necking the cylinder, the absorption tubing will retard 3cattered radiation and serve as additional insulation in that area. To further minimize the 10~8 of scat-tered radiation, a one war light transmitting coating, known in the glass art, may be applied to the inner surface of the ~acket. Such one wny transparent coating would allow light to pass unl-directionally into ths cylinder but not out. Those coatings may act a8 a second reflecting surface bouncing back ~cattered radlstlon and retaining it within the collector tube.
- : - - : , . .
- - - . ,, , . . . - : .
, . . - : - ~ ~,
Claims (7)
PROPERTY OR PRIVILEGE IS CLAIMED ARE DEFINED AS FOLLOWS:
1. A glass solar energy collector tube comprising an outer cylindrical evacuated jacket having a reflective coating on its inner surface extending around approximately half the circumference of the jacket and constituting a concave mirror, inner glass absorption tubing circulating heat storing fluid in and out of the jacket, said tubing lying in the focal plane of the concave reflecting coating, glass connecting means between the outer jacket and the inner tubing to support and position the tubing within the jacket, and blackening means associated with the inner tubing to increase the absorption of heat energy, the jacket comprising a main elongated cylindrical body portion having a central longitudinal axis, a sealed necked entry portion coaxial with the longitudinal axis, and a diminished rounded end, and the reflecting coating extending the length of the main elongated cylindrical body portion of the jacket, the absorption tubing for circulating the heat storing fluid entering through the sealed entry of the jacket and being offset in the main body portion, extending nearly the length of the main body portion of the jacket, and doubling over upon itself defining parallel ingress and egress legs, one of said legs lying along the principal axis of the concave mirror and the other leg of the inner tubing paralleling said one leg and being disposed between said one leg and the longitudinal axis of the body portion of the jacket for capturing scattered radiation, said one leg being spaced from said reflecting coating, and said legs being similarly offset to exit the sealed necked entry of the jacket.
2. A glass solar energy collector tube as in claim 1, wherein the glass jacket is coated on its inner surface exclusive of the mirrored surface with a one way light transmitting sub-stance which will transmit light from outside the jacket but will prevent transmission in the opposite direction.
3. A glass solar energy collector tube as in claim 2, wherein the reflective coating is aluminum.
4. A glass solar energy collector tube as in claim 3, wherein the blackening means comprises a black opaque fluid circulating in the inner glass tubing.
5. A glass solar energy collector tube as in claim 3, wherein the blackening means comprises a black coating on the surface of the inner tube.
6. A glass solar energy collector tube as in claim 5, wherein the black coating is on the inner surface of the inner circulating tube.
7. A glass solar energy collector as in claim S, wherein the black coating is on the outer surface of the inner tube.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CA282,608A CA1071049A (en) | 1977-07-13 | 1977-07-13 | Solar collector apparatus |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CA282,608A CA1071049A (en) | 1977-07-13 | 1977-07-13 | Solar collector apparatus |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| CA1071049A true CA1071049A (en) | 1980-02-05 |
Family
ID=4109121
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CA282,608A Expired CA1071049A (en) | 1977-07-13 | 1977-07-13 | Solar collector apparatus |
Country Status (1)
| Country | Link |
|---|---|
| CA (1) | CA1071049A (en) |
-
1977
- 1977-07-13 CA CA282,608A patent/CA1071049A/en not_active Expired
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| US4080954A (en) | Solar collector apparatus | |
| US4026273A (en) | Solar fluid heater with electromagnetic radiation trap | |
| US4299203A (en) | Tubular solar collector system | |
| US4003366A (en) | Solar heat collector module | |
| US4186724A (en) | Solar energy collector | |
| US8430093B1 (en) | Solar collector using subreflector | |
| US4153042A (en) | Solar collector | |
| US4136673A (en) | Multimode solar energy collector and process | |
| US4124019A (en) | Tubular solar collector | |
| US9194378B2 (en) | Electromagnetic radiation collector | |
| JPS6361579B2 (en) | ||
| US4132222A (en) | Solar energy collector | |
| US4561424A (en) | Nontracking parabolic solar energy collector apparatus | |
| US4239033A (en) | Parabolic reflector unit for solar energy collector | |
| US4236506A (en) | Solar energy collector | |
| WO2012073664A1 (en) | Solar thermal collector tube | |
| GB2053455A (en) | Collectors for Solar Energy | |
| IE44135B1 (en) | Solar energy collector | |
| CA1071049A (en) | Solar collector apparatus | |
| JP2015059730A (en) | Solar heat collection device | |
| USRE30407E (en) | Solar heat collector module | |
| US6044840A (en) | Nonimaging solar collector | |
| US3958553A (en) | Solar energy trap | |
| JPS57198403A (en) | Curved reflector | |
| EP1194722A1 (en) | Solar collector system |
Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| MKEX | Expiry |