WO1996014543A1

WO1996014543A1 - Equipment for utilizing solar energy for heating closed spaces e.g. flats, rooms or foil tents

Info

Publication number: WO1996014543A1
Application number: PCT/HU1995/000054
Authority: WO
Inventors: Gábor GÖDE
Original assignee: Goede Gabor
Priority date: 1994-11-02
Filing date: 1995-10-31
Publication date: 1996-05-17
Also published as: HU9403145D0; AU3751995A; ZA959188B; TNSN95109A1

Abstract

Equipment group for utilizing solar energy for the purpose of heating closed spaces with a heat energy collecting subassembly connected to a heat utilizing equipment (100) having a heat exchanger (24) and storage cells (9) with heat storage medium (43) suitable for phase conversion enclosed in the storage cells (9), having at least one of the storage cells (9) a heater (11) serving for melting the heat storage medium (43), as well as a draining pipe (12) serving for removing the heated heat storage medium (43) from the storage cell, said draining pipe (12) connected by means of a suction pipe (12a) forming the continuation thereof to the receiving space (24a) of the heat exchanger (24), crystallizing tubes (25) being arranged in the heat exchanger space (24b), openings (25a) of the crystallizing tubes (25) being connected to the receiving space (24a) and outlet openings (25b) of the crystallizing tubes (25) being connected to a central collecting tank (31), a cutting device (32) being arranged at the outlet openings (25b) of each crystallizing tubes (25), the central collecting tank (31) being connected by means of a loading mechanism (36) to the storage cell (9).

Description

Equipment for utilizing solar energy for heating closed spaces e.g. flats, rooms or foil tents

The invention relates to an equipment group for utilizing solar energy for the purpose of heating closed spaces e.g. flats, rooms, or foil tents, having said equipment group one of more sun-position follower concentrator unit serving for collection of solar radiation, a heat energy collecting subasscmbly positioned at the focus of the concentrator and tilled with a primary heat transfer medium, further- more, a stand supporting the concentrator unit as well as a driving mechanism to rotate the concentrator unit, being said heat energy collecting subassembly connected to a heat utilizing equipment by means of a connecting pipeline that includes an inlet pipeline transporting hot primary heat transfer medium and an outlet pipeline transporting cooled primary heat transfer medium, while being the heat energy collecting subassembly and. or the heat utilizing equipment provided with one or more circulating unit e.g. circulating pump.

In both the temperate zone and cold zone of the world, the heating of flats. public establishments, industrial and other projects raises increased difficulties due to the more and more expensive primary energy sources and the increased costs of energy conversion.

The same problem also makes it difficult, to provide (he inhabitants of these regions with fresh vegetables during winter: in fact, maintaining the appropriate temperature in the foil tents and green-houses requires significant amount of energy which is also reflected in the prices.

In addition, the use of fuel to produce the heat energy necessary for the heating involves significant environmental pollution due to the emission of combustion products, while resulting in - among others - progressive green-house effect and developing acidic rain, which endanger the live organism in all the world.

In order to reduce the disadvantageous effects and to find new energy sources, a number of experiments were already made. The attempts of this kind include the equipment utilizing solar energy, ol which a number of versions have became know n so lar.

The solar energy utilizing dev ices most w idely used are the planar collectors and the silicon type solar cells.

The planar collectors have the disadvantage that they are capable of producing warm water only of temperature up to 80 to 90 C° even during the most favourable periods of solar radiation. In addition, they are unable to store the heat energy for long term.

Another disadvantage is. that - in order to avoid the danger of freezing - anti-freezing liquid with unfavourable heat conductivity instead of water shall be used: in addition, due to the frequent cloudy periods, this equipment and this method are unable to be used for heating.

The most unfavorable feature in the use of silicon-type solar cells is that the expensive solar cells of unreasonably large surface are unable to produce heat energy sufficient for heating during w inter. in lad. due to the energy production failure during cloudy periods in w inter, on the one hand, and the significant losses in energy due to the low efficiency of converting the direct current produced by the solar cells into heat energy, on the other hand, this equipment is capable of operating only in an unprofitable manner.

As opposed to the solutions described above, the patent description US 4.244.350 relates to a heat storage tank operated by solar energy, in which a heat transfer procedure is implemented. In this procedure, steam w ill be heated in a superheater pipeline system to produce overheated steam . However, the equipment has low efficiency, with its design unable to storage heat for long term.

The patent description US 4.391 .267 describes a heat storage material, the essence of which is. that a liquid crystal melt turns through phase conversion into crystalline form - at a certain temperature - in a spontaneous manner or by means of creating artificial cores by adding aggregate into the melt. The aggregate thus added w ill be dissolved, thus establishing a mixture. The aggregate may contain disodium hydrogen phosphate, dipotassium hydrogen phosphate of their ammonium- or sodium equivalent. In the material tending to congeal, the aggregate promotes the size and development of crystals to be controlled and prevents undesired hydrate crystal form from being developed from the melt.

The essence of the solution is. that the material melt during heating and storing heat energy -necessary for the phase conv ersion - emits heat energy during its re-conversion. The description, however, presents only a procedure that promotes the crystallization, without dealing with the recycling of he crystallized material.

Furthermore, the intermittent crystallization or that connected w ith continuous admixture is not included, no solution lot either the separation of the melt from the crystailine material by means of appropriate isolation or the r e-usage of the crystailine material in the solar energy utilization is included

The patent description US 4.355.627 presents a heat storage system using solar collector or heat pump. Its essence is. that separate heat accumulators of r egular geometric shape form a set in a larger collecting tank The shell of the heat accumulators contain heat conductive material e.g. glass, metal panicles, w hich encloses the heat storage material itself.

The disadv antage of this v ersion is that it is not a melt produced by means of heating from crystalline material, that is. the phase conv ersion procedure that is used for heat storage: therefore, the solution is unable to obtain high storage capacity to store the heat energy for longer period

The equipment group for solar energy utilization accor ding to the inv ention is aimed at eliminating the deficiencies of the consti uclions and procedures know n so far. and at developing a structure ensuring complete and sufficient heating by using solar energy during the cold period

The inv ention is based on the recognition that. by using the heat energy of solar radiation collected during the warm period for melting up-to-date crystailine materials and for pet forming then phase conversion inv olv ing heat energy utilization, and feeding the melt or solution stored until the beginn ing of the heattim season at the appropriate temperature by means of a feeding equipment of appropriate design into a heat exchanger, where the heat stored in the material fed into the heat exchanger will be transferred to a heating medium circulated in the heat exchanger: then, feeding the solidified crystal bars removed from the crystallizing tube and cut them into small pieces into a collective tank, while repeating this process until the utilization of the full quantity of melt. then, by using an equipment completely different from those known, the task can be solved.

According to the objective set. the equipment group according to the invention for utilizing solar energy for the purpose of heating closed spaces e.g. flats. rooms, or foil tents, having said equipment group one of more sun-position follower concentrator unit serving for collection of solar radiation, a heat energy collecting subassembly positioned at the focus of the concentrator and tilled with a primary heat transfer medium, furthermore, a stand supporting the concentrator unit as w ell as a driving mechanism to rotate the concentrator unit, being said heat energy collecting subassembly connected to a heat utilizing equipment by means of a connecting pipeline that includes an inlet pipeline transporting hot primary heat transfer medium and an outlet pipeline transporting cooled primary heat transfer medium, while being the heat energy collecting subassembly and or the heat utilizing equipment provided with one or more circulating unit e.g. circulating pump - is designed in a manner, that the heat utilizing equipment has a heat exchanger and storage cells located in the surroundings of the heat exchanger, with heat storage medium e.g. crystalline salt suitable for phase conversion enclosed in the storage cells, having at least one of the storage cells a heater connected to the connecting pipeline and serving for melting the heat storage medium, as well as a draining pipe serving for removing the heated heat storage medium from the storage cell, being said draining pipe connected by means of a suction pipe forming the continuation thereof to the receiving space of the heat exchanger, being said heat exchanger provided with a heat exchanger space separated from the receiving space as well as a liquid inlet tube suitable to inlet the secondary heat transfer medium into the heat exchanger space and a liquid outlet lube suitable to drain the secondary heat transfer medium off the heat exchanger space: crystallizing lubes are arranged in the heat exchanger space, being the inlet openings of the crystallizing tubes connected to the receiving space while the outlet openings of the crystallizing tubes connected to a central collecting tank, being both the inlet openings and the output openings of the crystallizing tubes terminated by pipe closing valves and a feeding subassembly is associated with and mounted above each crystallizing tube: a cutting device is arranged at the outlet openings of crystallizing tubes each, facing the central collecting tank, while being the central collecting tank connected by means of a loading mechanism to the storage cell.

A further criterion of the equipment group according to the invention for solar energy utilization may be that the heat exchanger of the heat utilizing equipment and or the storage cells are provided with heat insulating sheathing.

In a version of the invention, at least part of the storage ceils is mounted with temperature monitoring subassembly suitable to measure and indicate the temperature of the heat storage medium. In respect of the embodiment, it is favourable if the crystallizing tubes are provided with an out-thrust unit each. e.g. a piston that can be moved along the crystallizing tube. The pipe closing valves of the crystallizing tubes are linked with a driving subassembly suitable to move the pipe closing valves intermittently.

In another version of the equipment group, a crystal hole is formed near the outlet opening of the crystallizing tube e.g. on the pipe closing valve covering the outlet opening, with a crystal seed placed within the crystal hole.

In a preferred embodiment of the invention, the heat utilizing equipment is provided with state sensing elements serving for measuring the parameters of the primary heat transfer medium, the heat storage medium and the secondary heat transfer medium as well as with actuators serving for altering the parameters, The stale sensing elements and the actuators are connected by means of a control unit to a computing device e.g. computer.

In respect of the equipment group for solar energy utilization, it is advantageous, that the cutting device is mounted with a rotary knife. A heat pre-exchanger is mounted between the storage cell and the heat exchanger.

The equipment has the advantage that, due to its design and operation completely different from those know n so far. it is suitable to convert the solar energy collected during the sunny periods of spring, summer and autumn into heat energy, to store the heat energy for long term for using it during winter, thus ensuring the heating and warm water supply, as the case may be. even during the cloudy periods.

A further advantage is that the dimensions of the equipment enable it to be installed in living houses. The manufacture and the assembly or the operation raises no major problems.

In the following, the invention will be described in detail, by means of an exemplary embodiment, based on drawings.

Fig. 1 show s a version of the equipment, in a longitudinal sectional view.

Fig. 2 show s a view of the equipment represented in Fig. 1 . viewed from the direction II.

Fig. 1 show s the 1 concentrator unit which consists of a paraboloid mirror in this exemplary embodiment. The 3 supporting structure connects the 2 heat energy collecting subassembly located in the focus of the 1 concentrator unit to the 1 concentrator unit, being said 2 heat energy collecting subassembly connected by means of the 4a connecting pipeline consisting of the 4b inlet pipeline and the 4a connecting pipeline to the 5 pipeline of rigid wall.

This 5 pipeline of rigid wall also includes the 6 circulating pump charged with the task of circulating the 42 primary heat transfer medium between the 2 heat energy collecting subassembly and the 1 1 heaters of each 9 storage cell in the 100 heat utilizing equipment.

The I concentrator unit is provided with the 8 stand and the 7 driving mechanism that moves the 1 concentrator unit according to the position of the sun.

Fig. 1 also show s the 100 heat utilizing equipment composed of the 9 storage cells provided with 10 heat insulating mantle and the 24 heat exchangers. Each of the 9 storage cells is provided with the 1 1 heater connected to the 5 pipeline of rigid wall.

The 9 storage cell is also provided with the 12 draining pipe which connects through the 12a suction pipe as a continuation thereof to the 24a receiving space of 24 heat exchanger. In this exemplary embodiment. the 16 pump is also installed into the 12a suction pipe, which feeds the 43 heat storage medium contained in the 9 storage cell to the 24 heat exchanger.

At its end connecting to the 24a receiving space of the 24 heat exchanger, the 12a suction pipe is provided with the 1 7 closing valve which is one of the 41 actuators - not shown in the figure - ensuring the proper function of the equipment group.

The 23 heat pre-exchanger - not represented in the figure - can be mounted around the 12a suction pipe.

The 24 heat exchanger - as show n in Fig. 1 - is divided into the 24a receiving space and the 24b heat exchanger space. The 24b heat exchanger space is in connection with the 26 liquid inlet tube and the 27 liquid outlet lube. The 24b heat exchanger space also accommodates the 25 crystallizing tubes passing through it. The 25a inlet opening of each 25 crystallizing lube communicates with the 24a receiv ing space of the 24 heat exchanger, while the 25b outlet opening of each 25 crystallizing tube communicates with the 31 central collecting tank mounted on the 37 fool located below the 24 heat exchanger. The 25a inlet opening of the 25 cry stallizing lube is terminated by the 30a pipe closing valve, while the 25b outlet opening of the 25 crystallizing tube is terminated by the 30b pipe closing valve. Both the 30a pipe closing valves and the 30b pipe closing valves are actuated by means of the 30c driving subassembly w hich, in this exemplary embodiment, consists of the pneumatic 14 feeding subassembly. It shall be noted here that the 14 feeding subassembly may also be of hydraulic function with electronic control, pt ov ided that it w ill be capable of opening the 30a pipe closing valves terminating the 25a inlet openings of the 25 crystallizing lubes as w ell as the 30b pipe closing valves terminating the 25b inlet onenin gs to an arbitral , extent in an intermittent operation

In order to ensure the proper operation, it is reasonable to arrange 30d crystal hole near the 25b outlet opening of the 25 crystallizing lube, that contain ingredient accelerating the crystallization of the 43 heat storage medium in the 25 crv stalhzing tube Mounted below the 25 crystallizing tubes near the 25b outlet openings, the 31 central collecting lank accommodates the 32 cutting dev ice w hich, in this embodiment, consists of the 33 rotary knile composed of sev eral culling blades in a petal-like arrangement as well as of the 34 cutting dev ice driv ing motor. The arrangement of the 33 rotary knife is shown in Fig. 2. The 31 central collecting tank also accommodates the 36 loading mechanism which returns the 43 heat storage medium broken into small pieces into the 9 storage cell from which it was originally started. The 36 loading mechanism is driven by the 35 loading mechanism motor located below outside the 31 central collecting tank.

During the operation, the 1 concentrator unit including one or more sun position follower paraboloid mirrors controlled by means of electronic circuits and provided with the 7 driving mechanism and the 8 stand is installed on the roof of the building to be heated or at another unshaded place, while the 42 primary heat transfer medium heated by the radiated heat energy in the pipe spiral of the 2 heat energy collecting subassembly located at the focus of the 1 concentrator unit will be transferred by means of the 6 circulating pump through the 4a connecting pipeline and. then, the 5 pipeline of rigid wall to the 100 heat utilizing equipment located e.g. in the cellar of the building to be served or in another cave made suitable for this purpose.

The hot 42 primary heat transfer medium flow ing in the 1 1 heater located vertically within the 9 storage cell containing crystalline material as the 43 heat storage medium melts and. then, overheats the crystalline material contained in the 9 storage cell, while the 42 primary heat transfer medium already cooled returns through the 1 1 heater, the 5 pipeline of rigid w all and the 4b inlet pipeline of the 4a connecting pipeline vertically upwards to the 2 heat energy collecting subassembly mounted on the 1 concentrator unit. Thus, the first cy cle is completed. The 43 heat storage medium melt in the 9 storage cell containing crystalline material as 43 heat storage medium in the manner described above will be transferred by means of the 16 pump through the 12a suction pipe and the 17 closing valve previously opened under the control of the 39 control unit connected together with the 38 computing device - not show n in Fig. 1 - to the 24a receiving space of the 24 heat exchanger.

When the 24a receiving space is full, the 40 slate sensing element supplies a signal to the 39 control unit which, under the control of the 38 computing device, closes the 1 7 closing valve by means of the 41 actuator and. by operating the 1 8 valve actuating motor, rotates the upper 22 valve disc by means of the 21 clutches mounted on the 20 shaft, thereby opening the 25a inlet openings of the 25 crystallizing tubes located in the 24b heat exchanger space. thus allow ing the 25 crystallizing tubes to be filled w ith t he 43 heat storage medium. The overheated 43 heat storage medi um in the 25 crystallizing tubes w ill be progressiveh cooled below the point of congelation, thus giving way to the crystallization of the 43 heat storage medium by means of the crystal seeds located in the 30d cry stal hole formed preferably near the 25b outlet openings of the 25 crystallizing tubes, while transferring its total crystallization- i. e. phaseconversion heat energy to the 44 secondary heat transfer medium circulated in the 24b heat exchanger space of the 24 heal exchanger

On completion of the crystallization, the 39 control unit, by starting the 18 valve actuating motor again and operating the 21 clutches, also opens the lower 22 valve disc located at the 25b outlet opening of the 25 crystallizing tube. Then, the 14a out-thrust unit of the 14 feeding subassembly also enters into action and pushes the 43 heat storage medium solidified into crystalline bars progressively through the 25b outlet openings of the 25 crystallizing tubes out of the 25 crystallizing lubes downwards.

The material mowing downwards will be cut into small pieces by the 33 rotary knife driven by the 34 cutting device driving motor and the 43 heat storage medium thus milled will be accumulated in the 31 central collecting tank until the melt will be completely emptied from the 9 storage cell just processed. Then, the 39 control unit sets the 35 loading mechanism motor into operation which, by means of the 36 loading mechanism - of screw-conveyor type in this exemplary embodiment - feeds the 43 heat storage medium accumulated at the bottom of the 31 central collecting lank into the empty 9 storage cell.

It shall be noted here that it is not necessary to associate individual 36 loading mechanism to each 9 storage cell: instead, by means of subassemblies of appropriate design, a single 36 loading mechanism can also be used which, by means of one of the 41 actuators under the control of the 39 control unit, will alway s be directed to the appropriate 9 storage cell.

Then, in a similar manner as described above, the 43 heat storage medium contained still in overheated state in the next 9 storage cell w ill be used until the dominant pan of the melt is used up or at the end of the heating season, the heating is switched off. thus closing the cycle II until the next cold season.

The 44 secondary heat transfer medium heated in the 24b heat exchanger space w ill be transferred through the 27 liquid outlet tube by means of a circulating pump through e.g. radiators located within the flat in a manner known in itself, where its heat energy is transmitted and. then, the 44 secondary heat transfer medium returns through the 26 liquid inlet tube of the 24 heat exchanger to the 24 heat exchanger, thus, the cycle III w ill also be closed.

It shall be noted that the 44 secondary heat transfer medium can be used not only for heating purposes: instead, it is also suitable to produce household warm water directly or indirectly.

The solar energy utilizing equipment according to the invention is well suitable to collect, store the heat energy from solar radiation and recuperate it during w inter.

Claims

1. Equipment group for utilizing solar energy for the purpose of heating closed spaces e.g. flats, rooms, or foil tents, having said equipment group one of more sun-position follower concentrator unit serving for collection of solar radiation, a heat energy collecting subassembly positioned at the focus of the concentrator and filled with a primary heat transfer medium, furthermore, a stand supporting the concentrator unit as well as a driving mechanism to rotate the concentrator unit, being said heat energy collecting subassembly connected to a heat utilizing equipment by means of a connecting pipeline that includes an inlet pipeline transporting hot primary heat transfer medium and an outlet pipeline transporting cooled primary heat transfer medium, while being the heat energy collecting subassembly and or the heat utilizing equipment provided with one or more circulating unit e.g. circulating pump characterized by that the heat utilizing equipment (100) has a heat exchanger (24) and storage cells (9) located in the surroundings of the heat exchanger, with heat storage medium (43) e.g. crystalline salt suitable for phase conversion enclosed in the storage cells (9). having at least one of the storage cells (9) a heater (11) connected to the connecting pipeline (4a) and serving for melting the heat storage medium (43). as well as a draining pipe (12) serving for removing the heated heat storage medium (43) from the storage cell, being said draining pipe (12) connected by means of a suction pipe (12a) forming the continuation thereof to the receiving space (24a) of the heat exchanger (24). being said heat exchanger (24) provided with a heat exchanger space (24b) separated from the receiving space (24a) as well as a liquid inlet tube

(26) suitable to inlet the secondary heat transfer medium (44) into the heat exchanger space (24b) and a liquid outlet tube (27) suitable to drain the secondary heat transfer medium (44) off the heat exchanger space (24b): crystallizing tubes (25) are arranged in the heat exchanger space (24b). being the inlet openings (25a) of the crystallizing tubes (25) connected to the receiving space (24a) and the outlet openings (25b) of the crystallizing tubes (25) connected to a central collecting lank (31). being both the inlet openings (25a) and the outlet openings (25b) of the crystallizing tubes (25) terminated by pipe closing valves (30a. 30b) and a feeding subassembly (14) is associated with and mounted above each crystallizing lube (25): a cutting device (32) is arranged at the outlet openings (25b) of crystallizing tubes (25) each, facing the central collecting tank (31). while being the central collecting tank (31) connected by means of a loading mechanism (36) to the storage cell(9).

2. Equipment group for utilizing solar energy as in claim 1. character ized by that the heat exchanger (24) of the heat utilizing equipment (100) and or the storage cells (9) are provided with heat insulating sheathing.

3. Equipment group for utilizing solar energy as in claim 1 or 2. characterized by that at least part of the storage cells (9)is mounted with temperature monitoring subassembly (15) suitable to measure and indicate the temperature of the heal storage medium (43).

4. Equipment group for utilizing solar energy as in any of the claims 1 to 3. characterized by that the crystallizing tubes (25) are provided with an out-thrust unit (14a) each. e.g. a piston that can be moved along the crystallizing tube (25) back and forth.

5. Equipment group for utilizing solar energy as in any of the claims 1 to 4. characterized by that the pipe closing valves (30a.30b) of the crystallizing tubes (25) are linked with a driving subassembly (30c) suitable to move the pipe closing valves (30a.30b) intermittently.

6. Equipment group for utilizing solar energy as in any of the claims 1 to 5. characterized by that a crystal hole (30d ) is formed near the outlet opening (25b) of the crystallizing tube (25) e.g. on the pipe closing valve (30b) covering the outlet opening (25b). with a crystal seed (30e) placed within the crystal hole (30d).

7. Equipment group for utilizing solar energy as in any of (he claims 1 to 6. c h a rac terized by that the heat utilizing equipment (100) is provided with state sensing elements (40) serving for measuring the parameters of the primary heat transfer medium (42). the heat storage medium (43) and the secondary heat transfer medium (44) as well as with actuators (41) serving for altering the parameters.

8. Equipment group for utilizing solar energy as in claim 7. characterized by that the slate sensing elements (40) and the actuators (41 ) are connected by means of a control unit (39) to a computing device (38 ) e.g. computer.

9. Equipment group for utilizing solar energy as in any of the claims 1 to 8. characterized by that the cutting device (32) is mounted with a rotary knife (32a).

10. Equipment group for utilizing solar energy as in any of the claims 1 to 9.

characterized by that a heat pre-exchanger (23) is mounted between the storage cell (9) and the heat exchanger (24).