ENERGY SYSTEM AND METHOD, AND DATA CARRIER COMPRISING INSTRUCTIONS THEREFOR

Abstract

A system including a photovoltaic panel having a first heat exchanger for absorbing heat from the panel and/or from the environment by a heat exchanging fluid, connected to a heat pump. A second heat exchanger is provided for absorbing heat by the heat exchanging fluid and a control means for controlling a flow of the heat exchanging fluid through the first heat exchanger and/or the second heat exchanger. The heat pump is arranged to cool the heat exchanging fluid. The system has the following operating modes: a first mode in which cooled heat exchanging fluid is fed to the first heat exchanger; and a second mode in which cooled heat exchanging fluid is fed to the second heat exchanger and then fed to the first heat exchanger.

Claims

1. A system, comprising: at least one photovoltaic panel having at least one first heat exchanger for absorbing heat from said panel and/or from the environment by a heat exchanging fluid, said at least one first heat exchanger having an inlet for feeding heat exchanging fluid thereto and an outlet for discharging heat exchanging fluid therefrom; a heat pump having an inlet connected to the outlet of the at least one first heat exchanger for receiving heat exchanging fluid from the outlet of the at least one first heat exchanger via a first conduit and an outlet connected to the inlet of the at least one first heat exchanger for feeding heat exchanging fluid to the at least one first heat exchanger via a second conduit; a third conduit connecting the second conduit to a second heat exchanger for absorbing heat by the heat exchanging fluid; and a control means for controlling a flow of the heat exchanging fluid trough the first conduit and/or the second conduit and/or the third conduit, wherein said heat pump is arranged to discharge heat from the heat exchanging fluid, thereby cooling the heat exchanging fluid, the system having at least the following operating modes: a first mode wherein at least a part of said cooled heat exchanging fluid is fed to the at least one first heat exchanger via the second conduit; and a second mode, wherein at least a part of said cooled heat exchanging fluid is fed to the second heat exchanger via said third conduit and then fed to the inlet of the at least one first heat exchanger.

2. The system according to claim 1, wherein said system comprises at least two of said photovoltaic panels, each photovoltaic panel having a said first heat exchanger having a said inlet and a said outlet, and wherein, at least in the second mode of the system, the system is switchable between a first configuration wherein said control means are arranged to feed heat exchanging fluid to all of the first heat exchangers and a second configuration wherein said control means are arranged to feed heat exchanging fluid to some, but not all, of the first heat exchangers.

3. The system according to claim 1, wherein said system comprises a first heat exchanger bypass conduit that connects the second conduit to the first conduit and at least one controllable three-way valve connecting the first heat exchanger bypass conduit to the second conduit and/or the first conduit.

4. The system according to claim 2, wherein said control means are arranged to feed heat exchanging fluid to some, but not all, of the first heat exchangers and/or to at least partly return to the heat pump via the first heat exchanger bypass conduit based on at least one of the following: a temperature of the heat exchanging fluid: at or downstream of the outlet of the heat pump; at or upstream of the inlet of the at least one first heat exchanger; at or downstream of the outlet of the at least one first heat exchanger, the ambient temperature.

5. The system according to claim 2, wherein said control means are arranged to feed heat exchanging fluid to some, but not all, of the first heat exchangers and/or to at least partly return to the heat pump via the first heat exchanger bypass conduit based on at least one of the following: a cooling capacity of the heat pump; heat absorption of the heat exchanging fluid in the second heat exchanger, and heat absorption the heat exchanging fluid in the respective first heat exchangers.

6. The system according to claim 2, further comprising at least one first controllable valve between the outlet of each one or multiple of the first heat exchangers and the first conduit and/or between the second conduit and the inlet of each of the one or multiple first heat exchangers, the first controllable valves being operatively connected to the control means, wherein the control means are arranged for adjusting the first controllable valves independently from each other between an open and a closed position to control the flow of heat exchanging fluid through the respective one or multiple first heat exchangers.

7. The system according to claim 1, further comprising a fourth conduit connecting the first conduit to a third heat exchanger for discharging heat from the heat exchanging fluid, wherein at least in the second mode substantially no heat exchanging fluid is fed to the third heat exchanger via the fourth conduit, and in a third mode of the system at least a part of the heat exchanging fluid is fed to the third heat exchanger via the fourth conduit, wherein the fourth conduit is connected to the first conduit via a second controllable three-way valve, upstream and/or downstream of the third heat exchanger, wherein the second controllable three-way valve is operatively connected to the control means, wherein the control means are arranged for adjusting the second controllable three-way valve between an open and a closed position to control the flow of heat exchanging fluid through the fourth conduit.

8. The system according to claim 1, wherein said heat pump is configured to be at least partly powered by electrical energy generated by said at least one photovoltaic panel.

9. The system according to claim 1, further comprising a heat buffer for storing heat, wherein said heat pump is arranged to heat the heat buffer.

10. The system according to claim 9, wherein the heat buffer comprises a container with an inlet for filling it with a heat buffer fluid and an outlet for discharging heat buffer fluid from the container.

11. The system according to claim 9, wherein the system further comprises a fifth conduit, connected to the outlet of the heat buffer for letting out heated heat buffer fluid, or in heat exchanging contact with the heat buffer fluid to heat fluids flowing through the fifth conduit.

12. The system according to claim 1, wherein in a fourth mode of the system, at least part of the heat exchanging fluid is fed to the at least one first heat exchanger via the second conduit and the heat pump is arranged to heat the heat exchanging fluid, thereby discharging heat from a heat pump fluid and thus cooling the heat pump fluid, and at least one of the following: a fourth heat exchanger is provided, wherein said cooled heat pump fluid is arranged for cooling central heating system fluid in said fourth heat exchanger, and a or said heat buffer fluid is cooled by the cooled heat pump fluid.

13. The system according to claim 1, further comprising at least one pump arranged for pumping the heat exchanging fluid through the first and/or second and/or third and/or fourth conduit, wherein the control means are operatively connected to the pump for controlling the flow of heat exchanging fluid caused by the pump.

14. The system according to claim 1, wherein the at least one first heat exchanger comprises a three dimensional fabric, the three dimensional fabric comprising two woven or knitted main surfaces which extend substantially parallel to each other at a distance from each other, wherein the main surfaces are interconnected by a plurality of piles, wherein said plurality of piles defines a plurality of flow paths therebetween between the inlet and outlet of the at least one first heat exchanger.

15. A method for absorbing heat from at least one photovoltaic panel and/or from the environment by a heat exchanging fluid, the photovoltaic panel having at least one first heat exchanger, the method comprising: a) running the heat exchanging fluid through the at least one first heat exchanger, so that it absorbs heat from its respective photovoltaic panel and/or from the environment; and b) running the heat exchanging fluid through a heat pump, and discharging heat from the heat exchanging fluid by the heat pump, thereby cooling the heat exchanging fluid, and c) switching between: a first mode of the method, wherein steps a) and b) are repeated and/or continuously conducted; and a second mode of the method, wherein steps a) and b) are repeated and/or continuously conducted and the method further comprises running the cooled heat exchanging fluid through a second heat exchanger.

16. The method according to claim 15 wherein the at least one photovoltaic panel comprises at least two photovoltaic panels, wherein in the second mode of the method, the method comprises running heat exchanging fluid through the at least one first heat exchanger of some, but not of all of the at least two photovoltaic panels.

17. The method according to claim 15, further comprising: d) measuring at least one parameter, the at least one parameter being at least one of the following: a temperature of the heat exchanging fluid at or downstream of the outlet of the heat pump; a temperature of the heat exchanging fluid at or upstream of the inlet of the at least one first heat exchanger; and a temperature of the heat exchanging fluid at or downstream of the outlet of the at least one first heat exchanger, running the heat exchanging fluid through the at least one first heat exchanger of some, but not of all of the at least two photovoltaic panels based on the at least one parameter.

18. The method according to claim 15, wherein in a third mode of the method the method comprises: e) bypassing the heat pump by running at least part of the heat exchanging fluid from the at least one first heat exchanger through a third heat exchanger for discharging heat from the heat exchanging fluid.

19. The method according to claim 15, further comprising at least partly powering the heat pump using electricity generated by the at least one photovoltaic panel.

20. A data carrier comprising instructions which, upon execution by a suitable control means of a system according to claim 1, cause the control means to perform the method comprising: a) running the heat exchanging fluid through the at least one first heat exchanger, so that it absorbs heat from its respective photovoltaic panel and/or from the environment; and b) running the heat exchanging fluid through a heat pump, and discharging heat from the heat exchanging fluid by the heat pump, thereby cooling the heat exchanging fluid, and c) switching between: a first mode of the method, wherein steps a) and b) are repeated and/or continuously conducted; and a second mode of the method, wherein steps a) and b) are repeated and/or continuously conducted and the method further comprises running the cooled heat exchanging fluid through a second heat exchanger.

Description

[0104] The invention will be explained further with reference to the attached figures, in which:

[0105] FIG. 1 shows a flow diagram of an exemplary embodiment of the system according to the invention;

[0106] FIGS. 2 — 5 show parts of the flow diagram of FIG. 1 for explaining different working modes of the system;

[0107] FIG. 6 is a schematic cross section through an exemplary type of a photovoltaic panel with a first heat exchanger as used in the system; and

[0108] FIG. 7 is a flow chart of an exemplary embodiment of the method according to the invention.

[0109] In the figures, like elements are referred to by like reference numerals.

[0110] The system of FIG. 1 comprises in this exemplary embodiment two photovoltaic panels 1. It will be clear for the skilled person that any desired number of photovoltaic panels 1 may be provided. Each photovoltaic panel 1 has a respective first heat exchanger 2 for absorbing heat from said panel 1 and/or from the environment by a heat exchanging fluid. The two first heat exchangers 2 each have an inlet 3 for feeding heat exchanging fluid thereto and an outlet 4 for discharging heat exchanging fluid therefrom. A first conduit 5 connects the outlets 4 of the first heat exchangers 2 to an inlet 6 of a heat pump 7. The heat pump 7 is arranged to either discharge heat from the heat exchanging fluid, thereby cooling the heat exchanging fluid, or to feed heat to the heat exchanging fluid, thereby heating the heat exchanging fluid, dependent on an operating mode of the system, as will be explained further below with respect to FIGS. 2 - 5. A second conduit 8 connects the outlet 9 of the heat pump 7 to the inlets 3 of the first heat exchangers 2. The first conduit 5 and second conduit 8 thus interconnect the heat pump 7 and first heat exchangers 2 for transporting heat exchanging fluid there between. A third conduit 10 is provided that connects the second conduit 8 to a second heat exchanger 11 for absorbing heat by the heat exchanging fluid. Downstream of the second heat exchanger 11 the third conduit 10 connects to the second conduit 8. The second heat exchanger 11 may be a heat exchanger arranged in, at or near a building, and may be used for cooling said building, for instance by having a second heat exchanging fluid that is cooled by the heat exchanging fluid and thereby able to cool the building, for example via an air conditioning system. Two controllable three-way valves 22 are provided between the third conduit 10 and second conduit 8, both upstream and downstream of the second heat exchanger 11. The skilled person however realizes, that a single controllable three-way valve 22 either upstream or downstream of the second heat exchanger 11 could suffice.

[0111] In a basic form said system may only comprise the above described features. However, said system may comprise any one or more of the below described features, in any desired combination.

[0112] The system according to this exemplary embodiment further comprises a first heat exchanger bypass conduit 12 that connects the second conduit 8 to the first conduit 5 and in this embodiment two controllable three-way valves 13 connecting the first heat exchanger bypass conduit 12 to the second conduit 8 and the first conduit 5. In other embodiments, a single controllable three-way valve 13 may suffice. Via said first heat exchanger bypass conduit 12 some or all of the first heat exchangers 2 may optionally be bypassed, such that it is possible with the system according to this embodiment to feed heat exchanging fluid to all of the first heat exchangers 2, some of the first heat exchangers 2, or none of the first heat exchangers 2.

[0113] The system according to this exemplary embodiment further comprises in total four first controllable valves 14, wherein a respective first controllable valve 14 is provided between the outlet 4 of each of the first heat exchangers 2 and the first conduit 5 and between the second conduit 8 and the inlet 3 of each of the first heat exchangers 2. Alternatively a single controllable valve 14 could have been used, either upstream or downstream of each first heat exchanger 1. Moreover, multiple first heat exchangers could be connected to the same one or more controllable valves 14.

[0114] The system according to this exemplary embodiment further comprises a fourth conduit 15 connecting the first conduit 5 to a third heat exchanger 16 for discharging heat from the heat exchanging fluid. Said fourth conduit 15 then connects to the second conduit 8 downstream of the third heat exchanger 16. Said third heat exchanger 16 may for example be a heat exchanger of the building and may be arranged for heating tap water by absorbing heat from the heat exchanging fluid, either directly or indirectly via a further heat exchanging fluid. In this exemplary embodiment the fourth conduit 15 is connected to the first conduit 5 via a second controllable three-way valve 17. Another second controllable three-way valve 17 is shown between the fourth conduit 15 and the second conduit 8. Obviously, only one second controllable three-way valve 17 could have been used, at any of the shown locations.

[0115] The system according to this exemplary embodiment further comprises a heat buffer 18 for storing heat, wherein said heat pump 7 is arranged to heat the heat buffer 18. The heat buffer 18 may for example comprise a container with an inlet for filling it with a heat buffer fluid and an outlet for discharging heat buffer fluid from the container. The system may further comprise a fifth conduit 19, which is in this embodiment in heat exchanging contact with the heat buffer fluid to heat fluids flowing through the fifth conduit 19. The fifth conduit 19 may for example connect to a heating or tap water system of the building.

[0116] The system according to this exemplary embodiment further comprises a fourth heat exchanger 20. Said fourth heat exchanger 20 may be in heat exchanging contact with the heat pump fluid circulating in the heat pump 7. For example, said fourth heat exchanger 20 may be part of a and/or arranged for cooling central heating system fluid, such that said building can be cooled using the central heating system. Two controllable three-way valves 21 are provided such that the flow of heat pump fluid to the heat buffer 18 and/or fourth heat exchanger 20 can be controlled. Alternatively, a single controllable three-way valve 21 could have sufficed, either upstream or downstream of the fourth heat exchanger 20.

[0117] The system further comprises a control means (not shown) for controlling a flow of the heat exchanging fluid trough the first conduit and/or the second conduit and/or the third conduit and/or the fourth conduit. Said control means may be arranged to control the controllable valves 14 and/or three-way valves 13, 17, 21, 22.

[0118] The system according to this exemplary embodiment further comprises a pump 23 arranged for pumping the heat exchanging fluid through the first conduit 5 and/or second conduit 8 and/or third conduit 10 and/or fourth conduit 15, wherein the control means are operatively connected to the pump 23 for controlling the flow of heat exchanging fluid caused by the pump.

[0119] The exemplary system of FIG. 1 can be operated in several operating modi, which will be described with respect to FIGS. 2 — 5. In the FIGS. 2 - 5 the parts of the system in use in that mode are printed in bold lines.

[0120] FIG. 2 shows a first mode in which the system can be operated in accordance with the invention. In the first mode at least a part of said cooled heat exchanging fluid that is cooled in the heat pump 7 is fed to the two first heat exchangers 2 via the second conduit 8. As a result of the cooled heat exchanging fluid being fed to the first heat exchangers 2, the two photovoltaic panels 1 are cooled, such that the efficiency of the photovoltaic panel may increase. In this first mode, the heat pump fluid of the heat pump 7 may increase in temperature by absorbing heat from the heat exchanging fluid, which heat pump fluid may be used for heating the buffer fluid in the heat buffer 18. This heated buffer fluid 18 may for example be used for heating a building or tap water of a building via the fifth conduit 19.

[0121] FIG. 3 shows a second mode in which the system can be operated in accordance with the invention. In the second mode the heat exchanging fluid that is cooled by the heat pump 7 first passes the second heat exchanger 11 prior to being fed to the first heat exchangers 2. As a result thereof, the cooled heat exchanging fluid may be used for cooling said building, for instance by having a second heat exchanging fluid that is cooled by the heat exchanging fluid and thereby able to cool the building, for example via an air conditioning system. The heat exchanging fluid increases in temperature in the second heat exchanger 11, but may still be cool enough to cool the at least one photovoltaic panel, such that the efficiency of the photovoltaic panel may increase. Also in this second mode, the heat pump fluid of the heat pump 7 may increase in temperature by absorbing heat from the heat exchanging fluid, which heat pump fluid may be used for heating the buffer fluid in the heat buffer 18. This heated buffer fluid 18 may for example be used for heating a building or tap water of a building via the fifth conduit 19.

[0122] In the second mode as shown in FIG. 3, the system is switchable between a first configuration wherein said control means are arranged to feed heat exchanging fluid to all of the first heat exchangers 2 and a second configuration wherein said control means are arranged to feed heat exchanging fluid to some, but not all, of the first heat exchangers 2. If some of the first heat exchangers 2 are bypassed, part of the heat exchanging fluid may be bypassed via the first heat exchanger bypass conduit 12. By feeding heat exchanging fluid to some, but not all, of the first heat exchangers 2 in the second configuration, the temperature increase of the heat exchanging fluid may be limited. For example, the control means may be arranged to feed heat exchanging fluid to some, but not all, of the first heat exchangers 2 and/or to at least partly return to the heat pump 7 via the first heat exchanger bypass conduit 12 based on at least one of the following: [0123] a temperature of the heat exchanging fluid, for example: [0124] at or downstream of the outlet of the heat pump 7; [0125] at or upstream of the inlets 3 of the first heat exchangers 2; [0126] at or downstream of the outlets 4 of the first heat exchangers 2, [0127] the ambient temperature; [0128] a cooling capacity of the heat pump 7; [0129] heat absorption of the heat exchanging fluid in the second heat exchanger 11, and [0130] heat absorption the heat exchanging fluid in the respective first heat exchangers 2.

[0131] In FIG. 3 both first heat exchangers 2 and the first heat exchanger bypass conduit 12 are printed in bold lines. It will however be clear for the skilled person that in the first configuration no heat exchanging fluid is transported via the first heat exchanger bypass conduit 12 and that in the second configuration either one of the two first heat exchangers 2 may be bypassed and thus no heat exchanging fluid may be transported therethrough.

[0132] It is noted that it is also possible to bypass both first heat exchangers 2, such that all heat exchanging fluid returns to the heat pump 7 without passing the first heat exchangers 2. Obviously, any other number of heat exchangers could have been chosen. Further, it is possible to limit the flow through one or more of the first heat exchangers 2. The limited flow through the first heat exchangers 2 may then be mixed with flow from the first heat exchanger bypass conduit 12 downstream of the first heat exchangers 2, to obtain a heat exchanging fluid of desirable temperature.FIG. 4 shows a third mode in which the system can be operated in accordance with the invention. In this third mode at least a part of the heat exchanging fluid is fed to the third heat exchanger 16 via the fourth conduit 15. As described above, said third heat exchanger 16 may be a heat exchanger of the building (and/or may be connected to the buffer) and may be arranged for heating tap water by absorbing heat from the heat exchanging fluid, either directly or indirectly via a further heat exchanging fluid. This third mode may be advantageous if the temperature increase of the heat exchanging fluid in the first heat exchangers 2 is large enough for the heat exchanging fluid to heat the tap water via the third heat exchanger 16.

[0133] FIG. 5 shows a fourth mode in which the system can be operated in accordance with the invention. In the fourth mode of the system, at least part of the heat exchanging fluid is fed to first heat exchanger 2 via the second conduit 8 and the heat pump 7 is arranged to heat the heat exchanging fluid, thereby discharging heat from a heat pump fluid and thus cooling the heat pump fluid. The cooled heat pump fluid is in this example used for indirectly cooling central heating system fluid in said fourth heat exchanger 20. Alternatively, said heat buffer fluid may be cooled by the cooled heat pump fluid. The heated heat exchanging fluid may be cooled down in the first heat exchanger 2. The fourth mode may for example be advantageous if a building is to be cooled during the night, such that the building may be cooled via the fourth heat exchanger 20, and wherein the heat exchanging fluid is able to discharge its heat via the first heat exchangers 2 which are located outside of the building in the cold night and thereby able to cool the heat exchanging fluid.

[0134] The system may be switched between any of the above described operating modi, or any other, not described operating mode.

[0135] FIG. 6 shows an exemplary embodiment of the photovoltaic panel 1 and the first heat exchanger 2 thereof. This FIG. 6 shows that the first heat exchanger 2 may comprise a three dimensional fabric, the three dimensional fabric comprising two woven or knitted main surfaces 30 which extend substantially parallel to each other at a distance from each other, wherein the main surfaces are interconnected by a plurality of piles 31, wherein said plurality of piles defines a plurality of flow paths therebetween between the inlet 3 and outlet 4 of the first heat exchanger 2. One of the main surfaces 30 may be in direct contact with the photovoltaic panel 1, such that the panel 1 and first heat exchanger 2 are in good heat exchanging contact. The other main surface 30 may comprise a fluid impermeable coating 32 applied thereto. The coating 32 may alternatively be a fluid impermeable layer. Optionally said three dimensional fabric may be arranged in a frame (not shown).

[0136] FIG. 7 shows in a flowchart a method 100 for absorbing heat from at least one photovoltaic panel and/or from the environment by a heat exchanging fluid, the photovoltaic panel having at least one first heat exchanger. The flowchart includes a step 101 of switching between a first mode M1, a second mode M2 and a third mode M3. Although the switching step 101 is shown to occur only once, practically the switching step 101 may be performed multiple times in order to switch between the first, second and third modes M1, M2, M3. After having performed any one or more of the modes M1, M2, M3 of the method for a desired amount of time, the method may be stopped or another mode may be selected. The first mode includes a first step 102 of running the heat exchanging fluid through the at least one first heat exchanger, so that it absorbs heat from its respective photovoltaic panel and/or from the environment, and a second step 103 of running the heat exchanging fluid through a heat pump, and discharging heat from the heat exchanging fluid by the heat pump, thereby cooling the heat exchanging fluid. According to the invention, in the first mode M1, these steps 102, 103 are repeated and/or continuously conducted, possibly until another mode M2, M3 is selected. The second mode M2 includes steps 102′ and 103′ which correspond to steps 102 and 103 of the first mode respectively, unless state otherwise. The second mode further comprises an additional step 104 of running the cooled heat exchanging fluid through a second heat exchanger. In an example embodiment of the method described in FIG. 7, step 102′ comprises running heat exchanging fluid through the at least one first heat exchanger of some, but not of all of the at least two photovoltaic panels. The method 100 further includes a measuring step 105, which is optional, of measuring at least one parameter, the at least one parameter being at least one of the following a temperature of the heat exchanging fluid at or downstream of the outlet of the heat pump; a temperature of the heat exchanging fluid at or upstream of the inlet of the at least one first heat exchanger; and a temperature of the heat exchanging fluid at or downstream of the outlet of the at least one first heat exchanger. During the step 102′ of running the heat exchanging fluid through the at least one first heat exchanger, running the heat exchanging fluid through the at least one first heat exchanger of some, but not of all of the at least two photovoltaic panels is based on the at least one parameter measured in the measuring step 105. The third mode M3 comprises a first step 102″ equal to step 102 of the first mode M1 unless stated otherwise. The steps 105, 102′, 103′, 104 of the second mode M2 are repeated and/or continuously conducted until anther mode is selected. The third mode M3 further comprises a step 106 of bypassing the heat pump by running at least part of the heat exchanging fluid from the at least one first heat exchanger through a third heat exchanger for discharging heat from the heat exchanging fluid. The steps 102″, 106 of the third mode M3 are repeated and/or continuously conducted until another mode is selected.

[0137] Although the invention has been described hereabove with reference to a number of specific examples and embodiments, the invention is not limited thereto. Instead, the invention also covers the subject matter defined by the claims, which now follow.

[0138] For example, it will be clear for the skilled person that the number and/or location of controllable valves and/or three-way valves may be chosen as desired. For example, instead of four first controllable valves 14, two first controllable valves 14 may be provided, either upstream or downstream of a said first heat exchanger 2. Also multiple first heat exchangers 2 can be connected to the same one or more controllable valves 14.