Thermosyphonic Fluid Circulation Patents (Class 126/638)
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Patent number: 11873743Abstract: An energy storage system converts variable renewable electricity (VRE) to continuous heat at over 1000° C. Intermittent electrical energy heats a solid medium. Heat from the solid medium is delivered continuously on demand. An array of bricks incorporating internal radiation cavities is directly heated by thermal radiation. The cavities facilitate rapid, uniform heating via reradiation. Heat delivery via flowing gas establishes a thermocline which maintains high outlet temperature throughout discharge. Gas flows through structured pathways within the array, delivering heat which may be used for processes including calcination, hydrogen electrolysis, steam generation, and thermal power generation and cogeneration. Groups of thermal storage arrays may be controlled and operated at high temperatures without thermal runaway via deep-discharge sequencing. Forecast-based control enables continuous, year-round heat supply using current and advance information of weather and VRE availability.Type: GrantFiled: February 20, 2023Date of Patent: January 16, 2024Assignee: Rondo Energy, Inc.Inventors: John Setel O'Donnell, Peter Emery von Behrens, Chiaki Treynor, Jeremy Quentin Keller, Matthieu Jonemann, Robert Ratz, Yusef Desjardins Ferhani
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Patent number: 10208433Abstract: A heating device (1) comprising: an energy well (2), a heat pump (3) which is adapted to take up and transfer heat from the energy well (2) by the aid of a line from the energy well to the heat pump (3) for transport of anti-freeze liquid, a heat extraction device (4) connected to a heat pump (3) which selectively can be brought into a connected and a disconnected position, thaw coils (5) for thawing ground surrounding the thaw coils (5), in which the anti-freeze liquid is transportable, which thaw coils (5) selectively can be connected and disconnected to the line from the energy well to the heat pump (3), a heat exchanger (7) connected to the heat extraction device (4) adapted to selectively transfer heat to the thaw coils (5) by the aid of the heat extraction device (4), a control system (6) which is adapted for controlling the heating device (1) whereby low temperature heat from the energy well (2) alternatively high temperature heat from the heat pump (3) and the heat extraction device (4) selectively caType: GrantFiled: November 28, 2016Date of Patent: February 19, 2019Assignee: EXPERTUS KEMITEKNIK ABInventor: Lennart Sjölén
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Patent number: 9920956Abstract: An absorber tube, especially for solar collectors in solar thermal power plants with at least one collector mirror, is provided. The absorber tube includes a metal tube for supplying and heating a heat transfer medium, a sheath tube surrounding the metal tube to form an annular space that can be evacuated, a wall extending through the sheath tube and the metal tube to seal the annular space, and a getter material binding free hydrogen in the annular space. The absorber tube has a temperature variation device that changes the temperature of the getter material and the wall.Type: GrantFiled: October 26, 2010Date of Patent: March 20, 2018Assignee: SCHOTT SOLAR AGInventor: Thomas Kuckelkorn
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Patent number: 9412960Abstract: There is disclosed photovoltaic device structures which trap admitted light and recycle it through the contained photosensitive materials to maximize photoabsorption. For example, there is disclosed a photosensitive optoelectronic device comprising: a first reflective layer comprising a thermoplastic resin; a second reflective layer substantially parallel to the first reflective layer; a first transparent electrode layer on at least one of the first and second reflective layer; and a photosensitive region adjacent to the first electrode, wherein the first transparent electrode layer is substantially parallel to the first reflective layer and adjacent to the photosensitive region, and wherein the device has an exterior face transverse to the planes of the reflective layers where the exterior face has an aperture for admission of incident radiation to the interior of the device.Type: GrantFiled: May 3, 2011Date of Patent: August 9, 2016Assignee: THE REGENTS OF THE UNIVERSITY OF MICHIGANInventors: Stephen R. Forrest, Richard R. Lunt, Michael Slootsky
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Patent number: 9383120Abstract: An apparatus is disclosed including: a trough shaped reflector extending along a longitudinal axis and including at least one reflective surface having a shape which substantially corresponds to an edge ray involute of the absorber.Type: GrantFiled: March 20, 2015Date of Patent: July 5, 2016Inventor: Roland Winston
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Patent number: 9366483Abstract: In some embodiments, a temperature-controlled container for use within a refrigeration device includes: one or more sections of insulation material substantially defining one or more walls of a temperature-controlled container, the temperature-controlled container including an internal region; a thermally-insulated partition dividing the internal region to form a storage region and a phase change material region internal to the container, the thermally-insulated partition including a conduit between the storage region and the phase change material region; a thermal control device within the conduit; an aperture within a section of the insulation material substantially defining the container, the aperture between the phase change material region internal to the container and an external surface of the container; and a unidirectional thermal conductor positioned within the aperture, the unidirectional thermal conductor configured to transmit heat in a direction from the phase change material region to the exterType: GrantFiled: November 27, 2013Date of Patent: June 14, 2016Assignee: Tokitac LLCInventors: Philip A. Eckhoff, Lawrence Morgan Fowler, William Gates, Jennifer Ezu Hu, Muriel Y. Ishikawa, Nathan P. Myhrvold, Nels R. Peterson, Clarence T. Tegreene, Maurizio Vecchione, Lowell L. Wood, Jr., Victoria Y. H. Wood
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Patent number: 9310101Abstract: A set of heat pipes for solar collectors is provided. The set includes a plurality of heat pipes, each heat pipe being suitable for being laid out in a respective solar collector, and including a heat pipe fluid, a first sheet and a second sheet locally merged with each other and delimiting a reservoir. The reservoir containing the heat pipe fluid extends over a hot part for evaporating the heat pipe fluid and a cold part for condensing the heat pipe fluid, and is formed by an interstice between the two sheets. The reservoirs of at least two heat pipes are delimited by a same first sheet and a same second sheet.Type: GrantFiled: January 21, 2010Date of Patent: April 12, 2016Assignees: SOPHIA ANTIPOLIS ENERGIE DEVELOPPEMENT, COMMISSARIAT A L'ENERGIE ATOMIQUE ET AUX ENERGIES ALTERNATIVESInventors: Jean-Antoine Gruss, Christian Lenotre, Alain Marechal, Didier Rossi, Michel Wohrer
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Publication number: 20140283816Abstract: Natural circulation solar system for the production of sanitary hot water having a double circuit (solar and user ones) and provided with an air gap storage tank, realized so that the connection of vacuum pipes is allowed.Type: ApplicationFiled: November 11, 2011Publication date: September 25, 2014Applicant: GIANNELLI SOLARE DI GIANNELLI MARIO E C.Inventor: Mario Giannelli
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Patent number: 8757142Abstract: A solar collector, comprising: (a) a plurality of thermosiphon tubes in which water flows, each tube having a top opening and a bottom opening; (b) a top manifold having a water inlet and water outlet and disposed at the top opening of the tubes, providing both a water feed into at least one of the plurality of tubes and a water exit from the rest of the tubes; and (c) a bottom basin connecting the bottom openings of the tubes. In some embodiments the plurality of tubes are divided into at least one inlet tube and the rest as outlet tubes by a stopper disposed in the top manifold.Type: GrantFiled: June 25, 2009Date of Patent: June 24, 2014Inventors: Shlomo Gabbay, Abad Luis
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Patent number: 8485178Abstract: The forced recirculation solar water heating system with a backup water heater works through an electronic card that initiates the operation and activation of the water recirculators when there is a setpoint temperature difference between the panel and the storage tank detected by means of a bimetallic cable connected at one of the top ends of the panel and another bimetallic cable at the upper part of the storage tank. This storage tank has a series of safety check valves that prevent temperature loss due to hot water backflow to the hydraulic network or due to natural reverse recirculation, thus avoiding excess pressure in the system.Type: GrantFiled: May 29, 2008Date of Patent: July 16, 2013Assignee: Calentadores de America, S.A: DE C.V.Inventors: Rocio Meza Diaz, Carlos Alejandro Silva Imilan
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Patent number: 8459248Abstract: A solar water heating and cooling system including a solar energy collection assembly having a heat absorbing element, a heat exchanger and a shield. The system also includes a cooling assembly, the cooling assembly is integral with the shield. The system has a check valve in fluid communication with the solar collection assembly and the cooling assembly, and a fluid pump in fluid communication with the solar energy collection assembly. A working fluid is disposed within the solar energy collection assembly, the cooling assembly, the check valve and the fluid pump. A cooling loop is defined by the solar energy collection assembly, the cooling assembly and the check valve. When the fluid pump is off, the working fluid circulates through the cooling loop, but when the fluid pump is on, the working fluid circulates through a heating loop that is defined by the solar energy collection assembly and the fluid pump.Type: GrantFiled: December 6, 2010Date of Patent: June 11, 2013Assignee: SolarLogic, LLCInventors: Fredric Milder, Boaz Soifer, Bristol Stickney
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Publication number: 20130068418Abstract: One embodiment of the invention is a thermosiphon vessel for storing seasonal environment energy in the ground. The thermosiphon includes: a fluid vessel comprising a heat exchange tube, configured to contain a working fluid, and further configured to receive a fluid inlet and a fluid outlet; a wicking material arranged within the fluid vessel and configured to retain liquid-state working fluid substantially adjacent an inner wall of the heat exchange tube; a fluid level sensor arranged within the fluid vessel and configured to determine the level of liquid-state working fluid therein; and a pump arranged within the fluid vessel and configured to maintain the level of liquid-state working fluid below a threshold level within the fluid vessel. The pump is operable between an energy capture mode to absorb thermal energy from an above-ground heat source and an energy release mode to release thermal energy to an above-ground heat sink.Type: ApplicationFiled: March 16, 2012Publication date: March 21, 2013Inventors: Eric Joseph Gotland, Kent Stewart Udell
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Patent number: 8281783Abstract: A thermal absorber including a light-transparent reservoir having an alkali metal received therein, a housing sealingly coupled to the reservoir to define an enclosed volume, the housing including a thermal barrier wall that divides the volume into a cold chamber and a hot chamber, the cold chamber including a sump having a drain hole in fluid communication with the hot chamber, and at least one AMTEC cell supported by the cell supporting surface, the AMTEC cell extending through the cold chamber and the hot chamber.Type: GrantFiled: August 7, 2009Date of Patent: October 9, 2012Assignee: The Boeing CompanyInventor: Mark D. Bennett
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Publication number: 20120247455Abstract: Solar energy conversion systems and methods use solar collectors and working fluid management systems to provide both efficient and safe operation under a wide range of operating conditions. In one embodiment, a solar collector and at least one fluid accumulator preferably with an integral heat exchanger, and at least two mass flow regulator valves enable working fluid flow into and out of the fluid accumulator.Type: ApplicationFiled: August 6, 2010Publication date: October 4, 2012Applicant: ECHOGEN POWER SYSTEMS, LLCInventors: Michael Gurin, Timothy James Held, Jason D. Miller
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Patent number: 8220453Abstract: The present invention includes a solar water heating system including: a water tank to hold water to be heated, an heat transfer fluid circuit including an heat exchanger associated with said water tank to heat water therein, a solar collection means in communication with said heat exchanger, an inlet connection to carry heat transfer fluid from said solar collection means to said heat exchanger where said water will be heated; and an outlet connection to carry heat transfer fluid from said heat exchanger to said solar collection means where said heat transfer fluid will be heated, said heat transfer fluid circuit including a reversibly evaporable heat transfer fluid which will absorb heat from said solar collection means and which will transfer said heat to said water in said water tank by means of said heat exchanger; and an diversion path being provided in said heat transfer circuit, whereby when a portion of heat transfer fluid changes to a gaseous state in said solar collection means, heat transfer fluidType: GrantFiled: September 20, 2005Date of Patent: July 17, 2012Assignee: Rheem Australia Pty LimitedInventor: Brendan Vincent Bourke
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Publication number: 20120090599Abstract: A solar heating system for heating air beside a window is disclosed. The solar heating system effectively heats air beside a window in a room of a structure through use of one or more solar panels positioned to be heated by the sun and to transfer that heat to surrounding air via convection in moving air. In at least one embodiment, the solar panel may be a corrugated panel having at least one channel. The solar panel may be positioned such that as the solar panel is heated by the sun, heat is transferred from the solar panel to surrounding air via convection. The solar panel may be configured such that an upward flow of air forms when the air is heated, thereby creating a natural, warm air flow without need of a fan or other such device.Type: ApplicationFiled: October 19, 2011Publication date: April 19, 2012Inventor: Jeffrey Thomas Parana
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Patent number: 8113192Abstract: There is provided an evacuated tubular solar collector with an eccentric type manifold flange capable of changing flow of a heating medium and improving the electric heat performance of a manifold by employing an eccentric end cap with a fluid path and a baffle in the manifold and improving the structure of the manifold. The evacuated tubular solar collector may comprise an evacuated tubular solar collector; a manifold being installed at an upper position of the evacuated tubular solar collector and including a number of heat dissipation holes; eccentric end caps attached to both sides of the manifold, the eccentric end cap including a fluid path; and a baffle attached to an exit of the fluid path through which a fluid flows into. The fluid path and the baffle may be positioned tilted, thereby to improve uniform transfer of heat in the evacuated tubular solar collector.Type: GrantFiled: October 2, 2006Date of Patent: February 14, 2012Assignee: Korea Institute of Energy ResearchInventors: Hee Youl Kwak, Nam Choon Baek, Eung Sang Yoon, Soon Myeong Rhie
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Publication number: 20110206818Abstract: An improved solar oven with the ability to overcome recognized prior art limitations, such as temperature variation during prolonged cloudy periods is described. The solar oven according to the invention utilizes an enclosure similar to a box type oven and a thermosiphon (alt. thermosyphon) device to generate and maintain heat sufficient to cook food. The invention also encompasses a method of solar cooking utilizing an enclosure similar to a box type oven and a thermosiphon device.Type: ApplicationFiled: February 19, 2010Publication date: August 25, 2011Inventor: Arlus Walters
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Patent number: 7882832Abstract: Various embodiments of a fluid displacement system are disclosed. The system may include a reservoir containing a fluid in a liquid state and a first chamber hydraulically connected to the reservoir to receive the fluid from the reservoir. The first chamber may be configured to receive solar energy and configured to convert the received solar energy to vaporize the fluid. The system may also include a second chamber hydraulically connected to the first chamber to receive the vaporized fluid from the first chamber. The second chamber may be configured to condense the vaporized fluid, causing depressurization in the second chamber. The system may also include a hydraulic connection between the second chamber and a source of fluid to be displaced. The system may be configured such that the depressurization of the second chamber may cause fluid in the source of fluid to be displaced through the hydraulic connection.Type: GrantFiled: July 20, 2005Date of Patent: February 8, 2011Inventor: Claudio Filippone
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Patent number: 7870855Abstract: A solar heat collecting dome includes a frame having an odd number of frame elements extending upward and inward from a floor structure to a disk at the top of the dome. A dome shaped helical structure including two flexible tubes is woven to extend along and around the frame elements, with the dome shaped helical structure extending across alternating inner and outer sides of the frame elements, and with adjacent portions of the dome shaped helical structure extending across alternating inner and outer sides of each frame element. At an outer end of the dome shaped helical structure, the two tubes form an inlet and an outlet. At the inner end, the two tubes are joined. The frame may also include a fluid path, with the fluid moving in opposite directions in each of the frame elements.Type: GrantFiled: January 16, 2008Date of Patent: January 18, 2011Inventor: B. Michael Flaherty
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Patent number: 7798140Abstract: Solar collectors heat and self pump heat transfer fluid at reduced system pressure without mechanical intervention for heat exchange with hot water in a storage tank. Slugs of hot fluid are pumped by steam bubbles formed in solar collector tubes through an upper manifold and an exit-tube into an upper hot fluid reservoir. Hot fluid flows downward through a heat exchanger at the tank. Cold fluid returns to a lower reservoir. Vapor flows from the upper reservoir and is condensed by cooler water and walls of the lower reservoir. The cool fluid returns from the lower reservoir to a lower manifold supplying the collector tubes. Below ambient pressure is automatically established in the system. When heat build-up increases pressure in the system, fluid flows to a third closed variable volume reservoir. A float valve in the bottom of the third reservoir allows liquid to return to the system when it cools.Type: GrantFiled: October 6, 2009Date of Patent: September 21, 2010Assignee: Sunnovations LLCInventor: Arnoud van Houten
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Publication number: 20080047545Abstract: A method and an apparatus for the 24 hours a day conversion of the high difference of temperatures between two working mediums accumulating the Sun-radiation-heat gets concentrated by the parabolical mirror, during light-days, and the cosmic cold, during nights, into electro-power & refrigeration-output which are realized and called for service (under the shadow of this mirror or near this shadow), which method and apparatus provide not only to perform (fulfil) this conversion, but also to intensify the semiconductive thermoelectrical transformer as well as the heat-exchange of these heat-accumulating working mediums with the heat-absorbing and heat-transferring components of the absorption-refrigeration machines and heat-mechanical electro-generating machines.Type: ApplicationFiled: August 26, 2006Publication date: February 28, 2008Inventor: Harry Y. Zagalsky
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Patent number: 7318432Abstract: A solar collector plate (2) has a solar radiation receiving front absorber plane (3) that is wiped at its rear side by a cooling liquid (4) flowing in channels (5). Cavities (7), preferably behind the channels (5) and integrated in the solar collector plate (2), and that can be closed off by the very liquid flow (4), provide a closed air volume that gives a dampening effect regarding kickbacks and pressure transients in the liquid (4).Type: GrantFiled: October 11, 2002Date of Patent: January 15, 2008Assignee: Solarnor ASInventor: John Rekstad
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Patent number: 7277627Abstract: A water heater adapted to be positioned outside of a building and to interface with the plumbing system of the building. The water heater includes a water storage tank adapted to store water outside of the building, a means for heating the water in the tank, a base member supporting the tank outside of the building, and a plurality of water pipes communicating with the water tank. The water heater also includes a manifold that is mounted to the base member and includes a plurality of pipe unions adapted to interface between the plumbing system and the plurality of pipes to provide cold water to the tank and to remove heated water from the tank for use in the building.Type: GrantFiled: February 18, 2003Date of Patent: October 2, 2007Assignee: AOS Holding CompanyInventors: Dennis R. Hughes, Kevin M. Field
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Publication number: 20040099261Abstract: A solar thermal energy transmission system having a bellows that sealingly interconnects a first structure to a second structure is disclosed. The bellows includes a surface that is compatible with a molten salt and is configured to resiliently deform in response to contraction and expansion of at least one of the first and second structures, to thereby accommodate relative movement of the structure(s) to which it is coupled.Type: ApplicationFiled: November 22, 2002Publication date: May 27, 2004Inventor: Robert Zachary Litwin
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Publication number: 20030230300Abstract: A solar energy collecting device includes a housing confining a receiving space and formed with an opening for access into the receiving space. The housing has a transparent side wall. A thermal conductor has a heat-absorbing portion disposed in the receiving space of the housing, and a heat-radiating portion extending out of the receiving space via the opening. The thermal conductor includes a hollow heat-conducting member that defines a sealed chamber therein and that is formed with a thermal conductor layer in the chamber. The heat-absorbing portion absorbs solar energy when the housing is irradiated by solar radiation, and transmits the solar energy to the heat-radiating portion.Type: ApplicationFiled: August 21, 2002Publication date: December 18, 2003Inventor: Chin-Kuang Luo
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Publication number: 20030196652Abstract: A solar energy collector system for reducing heating, air conditioning and power consumption of a building structure. The solar energy collector system includes a housing structure, a collector plate, an insulating sheet positioned between the collector plate and a floor of the housing structure, a thermopile unit within the housing structure, and a fluid positioned below the collector plate. The fluid adjacent the collector plate is heated thereby rising to an upper portion of the housing structure and thermally conducting the thermopile unit for generating electricity. The cooled fluid then passes downwardly below the insulating sheet to a lower portion of the housing structure. A heat exchanger is utilized upon the opposite side of the thermopile unit for transferring the heat to a desired location within or outside of the building structure.Type: ApplicationFiled: April 22, 2002Publication date: October 23, 2003Inventor: Timothy J. Flick
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Publication number: 20030127089Abstract: A method of manufacturing an integral one-piece solar collector panel by a rotational moulding process is disclosed. The solar collector panel has a plurality of fluid ways extending between opposed ends and transverse headers opening into the open ends of the fluid ways. The panel is moulded by a rotational moulding process using mould faces with a non planar topography, eg in the form of a plurality of lines projecting outwardly proud of the remainder of the mould plate. This enables areas of the moulded body to be formed that are not hollow and form a solid wall in the moulded panel and other areas of the body to be formed that are hollow and form the fluid ways and headers. After the moulding of the panel has taken place the two opposed mould faces are moved towards each other to cause the contacting layers of mould material to firmly adhere to each other. This post moulding treatment step is not used in standard rotational moulding processes.Type: ApplicationFiled: September 10, 2002Publication date: July 10, 2003Inventors: Noel Richard Drummond, Gerard Anthony Litchfield, Marquis Charles Fabian
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Publication number: 20030121515Abstract: A loop counter-thermosyphon heat pipe solar collector includes a capillary in a loop heat pipe. The capillary has a top opening end with a damper attached thereon. Working fluid may be ejected through the top opening end and deflected by the damper and sprayed on the loop heat pipe wall located on a heating side to generate film evaporation for increasing thermal conduction effect. A partition is provided at an bottom opening end of the capillary to separate and balance working fluid to resolve the problem of liquid reversed flow carrying away heat energy at night time.Type: ApplicationFiled: December 28, 2001Publication date: July 3, 2003Applicant: Industrial Technology Research InstituteInventors: Li Yu-Chu, Tang Jenn-Chen
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Patent number: 6407328Abstract: A photovoltaic device for converting radiation energy into electric power, includes a front side exposed to radiation from a radiation source, a backside; and a cooling unit having a liquid medium, e.g. water, arranged between the front side and the radiation source. The liquid medium is surrounded by an envelope, and forms with the envelope a selective filter allowing passage of radiation useful for the photovoltaic effect and converting the longer wave radiation into hear which is immediately dissipated to substantially prevent heating of the photovoltaic module.Type: GrantFiled: February 2, 2001Date of Patent: June 18, 2002Assignee: PowerPulse Holding AGInventor: Jürgen Kleinwächter
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Publication number: 20010054419Abstract: A solar thermoaccumulator, including a parallel battery of closed-circuit vacuum solar pipes, and provided with a plurality of accumulation bulbs, which are either immersed in a primary conductive fluid that circulates in an annular chamber having an air space, whose internal wall is the containing wall of a reservoir containing a fluid to be heated; or are put in direct thermally conductive contact with tubular tangs that are attached to and inserted in a reservoir, is disclosed. The reservoir may be single reservoir, or may be associated with and sequentially in fluid communication with at least one other upstream, parallel aligned reservoir.Type: ApplicationFiled: June 20, 2001Publication date: December 27, 2001Inventor: Livio Terraneo
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Patent number: 6119682Abstract: The invention provides a low-profile, solar energy powered, thermosyphon-circulated water heater and storage device (10) comprising: a flat, tilted solar radiation absorber panel (12); an insulated hot fluid storage tank (18); a conduit (20) providing fluid communication between a lower area of said absorber panel (12) and said storage tank (18), and a further conduit (22) providing fluid communication between an upper area of said absorber panel (12) and an upper area of said storage tank (18) to complete a thermosyphonic path between said panel sand said tank.Type: GrantFiled: January 27, 1999Date of Patent: September 19, 2000Inventor: Haim Hazan
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Patent number: 6026806Abstract: To provide an inexpensive air-conditioned construction of floor and ceiling, by using as a heat accumulating agent water which is friendly to the human body and nature, and using a heat source solar energy or outside air temperature. The construction of the invention comprises a floor body and a ceiling body formed by a plurality of space portions and filled up with water, sunlight intercepting sections for permitting the contains to receive the sunlight, heating sections provided below the sunlight intercepting sections, outside air temperature receiving sections or outside heating means provided in place of the sunlight intercepting sections, and cooling sections provided above the outside air temperature receiving sections.Type: GrantFiled: June 20, 1997Date of Patent: February 22, 2000Assignee: Izena Co. Ltd.Inventor: Seiichi Maeda
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Patent number: 5537990Abstract: A solar water heating system includes a water storage tank to which a hot water outlet pipe and a cold water inlet pipe are connected. A solar-collector unit is mounted below the water storage tank. A downcomer pipe connects the water storage tank and the lower portion of the solar-collector unit. A return pipe connects the upper portion of the solar-collector unit and the water storage tank. A tube member is installed in the water storage tank and interconnects the downcomer pipe and the return pipe. The solar-collector unit, the downcomer pipe, the return pipe, and the tube member form a loop that is filled with deionized water.Type: GrantFiled: July 7, 1995Date of Patent: July 23, 1996Inventor: Jia-Shing Lee
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Patent number: 5261390Abstract: A system for heating a fluid (5) conveyed or contained in process equipment (7) comprises a layer of transparent thermal insulation (9) which partly covers the process equipment so that a section (13) is exposed to solar radiation and thus is heated by the solar radiation and thereby heats the fluid (5). The "window" defines a form of thermal diode concentrator in that the surface area of the "window" is great than that of the exposed section (13) of the process equipment (7) and thus the "window" in effect concentrates the solar radiation onto the exposed section (13) of the process equipment, and the transparent thermal insulation (9), albeit transparent, minimises heat loss from the fluid (5).Type: GrantFiled: April 1, 1991Date of Patent: November 16, 1993Inventor: John B. Lasich