NL2017689B1

NL2017689B1 - Roof energy system

Info

Publication number: NL2017689B1
Application number: NL2017689A
Authority: NL
Inventors: Geraldus Van Meurs Bart
Original assignee: Koppert Cress Ip B V
Priority date: 2016-10-31
Filing date: 2016-10-31
Publication date: 2018-05-18

Abstract

System for supplying energy to a building with a roof, such as a green house. The system has a thermal energy storage system (20) for providing heat and/or cooling to the building, with a heat storage well (21) and a cold storage well (22), and a thermal energy pump system for pumping a thermal energy system fluid into or from the heat storage well (21) and/or cold storage well (22). A solar energy collector system (8) is part of the system and is based on circulation of a heat transfer fluid having at least one solar collector unit (3), which during operation is exposed to solar radiation and arranged to transform the solar radiation to thermal energy in the heat transfer fluid. The solar energy collector system (8) is integrated with the thermal energy storage system (20).

Description

Field of the invention

The present invention relates to a system for supplying energy to a building having a roof, such as a greenhouse or industrial facility.

Background

Thermal Energy Storage (TES) systems are widespread and applied for both industrial and residential buildings. TES system may use warm and/or cold fluid storage tanks above ground or use warm and/or cold fluid wells below ground in e.g. the earth’s surface or soil. Underground thermal storage, however, poses restrictions on the use of such TES systems as a thermal energy balance must be maintained over a period of e.g. one year, wherein the temperature of thermal carrier fluids injected into a warm fluid well may be limited to a maximum temperature.

Furthermore, thermal solar collector systems are well known in various alternative implementations, using water or a water based (glycol) solution acting as a transfer medium for transporting thermal energy from a solar collector unit positioned on a roof top of a building to one or more rooms in a building. Solar collectors may have various forms, ranging from panel shaped collectors to water circulation systems integrated with structural and/or functional roof elements (or even road elements), such as insulation material layers. As a rule of thumb, all thermal solar collector systems are designed to maximize absorption of received solar radiation and to transform the solar radiation into heat energy using some circulating heat carrier fluid.

Summary

The present invention seeks to provide an improved system for supplying energy, such as heat, to a building. The system allows for a significant reduction in overall heating costs associated with conventional heating systems by supplying heat in an efficient and renewable fashion.

According to the present invention, a system of the type defined in the preamble is provided, wherein the system comprises a thermal energy storage system (TES) for providing heat and/or cooling to a building and having a heat storage well and a cold storage well. A thermal energy transfer system is provided for transferring thermal energy from the heat storage well and/or cold storage well using a thermal energy transfer fluid. Further, the system comprises a solar energy collector system based on circulation of a solar energy transfer fluid and having at least one solar collector unit, which during operation is exposed to solar radiation and arranged to transform the solar radiation to thermal energy in the solar energy transfer fluid The solar energy collector system is integrated with the thermal energy storage system by using the thermal energy transfer fluid as the solar energy transfer fluid.

It is noted that the thermal energy transfer system usually comprises a heat exchanger (or heat pump) to exchange thermal energy from the heat storage well/cold storage well (using a primary fluid) with thermal energy in the thermal energy transfer fluid (e.g. for use in a low temperature heating system in the building). To operate the thermal transfer system usually an

P6063948NL electric pump is used for controlling the amount of thermal energy transfer fluid flowing through the heat exchanger, thus requiring electrical power to operate the thermal energy storage system. The present invention allows for considerable reduction in heating costs spent on e.g. natural gas for providing additional heating energy as the system provides efficient absorption of solar radiation during circulation of the heat transfer fluid through the at least one solar collector unit. The thermal energy stored by the thermal energy storage system is then used for further heating purposes. Both components of the present invention embodiments allow to operate a building heating system on low temperature, e.g. allowing a radiating heating system, such as using floor or wall integrated heating elements. The use of a low temperature building heating system, allows to also use more cost-effective parts and simpler construction of the solar energy collector system as well.

In an advantageous embodiment the solar energy collector system comprises a separate cover structure (or enclosure) spanning across one or more solar collector units. The cover structure may be transparent to solar radiation and preferably exhibits minimal reflection. To enable long service life and durability of the cover structure, transparent plastic material may be used, such as plastic foils and/or plastic panels.

The cover structure may be arranged as an enclosure and shields the one or more solar collector units from unwanted cooling of the heat transfer fluid by e.g. cold atmospheric conditions (e.g. wind may circulate through the solar energy collector system during operation and actually cool down the heat transfer fluid by thermal convection and thermal conduction effects). The cover structure of the present invention therefore improves the overall thermal efficiency and heating capability of the system as thermal losses due to e.g. cold atmospheric conditions and winds are mitigated. Note that the cover structure need not provide a hermitically sealed enclosure as such and may permit particular openings for pipework, electric cables and the like. Of course, higher sealing capability of the cover structure facilitates further reduction of thermal losses.

In an advantageous embodiment, the cover structure spanning across the one or more solar collector units may be an arched or dome-like cover structure. An arched cover structure may be advantageous for e.g. a flat roof on which the one or more solar collector units are arranged. The arched cover structure provides excellent strength and durability and de-watering capabilities during rainy conditions, and the shape will also aid in resisting wind effects as the arched structure will be pushed onto the roof.

Short description of drawings

The present invention will be discussed in more detail below, with reference to the attached drawings, in which

Figure 1 shows a schematic diagram of a system for supplying energy to a building according to an embodiment of the present invention;

Figure 2 shows a three dimensional view of a system for supplying energy to a building according to an embodiment of the present invention;

Figure 3 shows a schematic view of a solar energy collector system according to an embodiment of the present invention; and

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Figure 4 shows a schematic block diagram of a further embodiment of the present invention.

Description of embodiments

For Thermal Energy Storage (TES) systems, overall yearly heat demand often surpasses available energy delivered by a TES system for e.g. heating a building. In situations where heating is provided through conventional methods (e.g. using natural gas based heating systems), it is then required to meet the total demand for heating. However, for various underground based TES systems a heat or thermal balance has to be maintained within prescribed legal bounds imposed by government bodies.

In light of the above, there is a need for an improved system for supplying heat to a building wherein the use of conventional heating is less relied upon.

Figure 1 shows a schematic view of a system 1 for supplying energy to a building according to an embodiment of the present invention. Figure 2 shows a three dimensional view of a solar energy collector system 8 as used in embodiments of the present invention system 1, Figure 3 shows a schematic view of such a solar energy collector system 8, and Figure 4 shows a further embodiment of the present invention system 1.

The system 1 comprises a thermal energy storage system 20 for providing heat and/or cooling to a building (e.g. using radiators or e.g. a low temperature floor heating system). The thermal energy storage system 20 is provided with a heat storage well (or buffer) 21, a cold storage well (or buffer) 22, and a thermal energy transfer system 23 transferring thermal energy from the heat storage well 21 and/or the cold storage well 22 using a thermal energy transfer fluid. The system 1 further comprises a solar energy collector system 8 based on circulation of a solar energy transfer fluid and having at least one solar collector unit 3, which during operation is exposed to solar radiation and arranged to transform solar radiation to thermal energy in the solar energy transfer fluid. The solar energy collector system 8 is integrated with the thermal energy storage system (TES) 20 by using the thermal energy transfer fluid as the solar energy transfer fluid.

The thermal energy transfer system 23 is e.g. implemented using a heat exchanger 23, allowing to physically separate the thermal energy transfer fluid from a fluid originating from the heat storage well 21. This allows, as indicated to have a flow F1 of fluid from the heat storage well 21 with a temperature T1, via the heat exchanger 23 to the cold storage well 22 with a temperature T2 (which is lower than T1 if heat energy is extracted).

The system 1 of the present invention allows for significant reduction in heating costs usually spent on e.g. natural gas based heating systems and allows for thermal energy to be absorbed, stored and used efficiently for heating purposes. In advantageous applications the solar energy collector system 8 is located on e.g. a roof of a building, such as a roof of a greenhouse, where greenhouses typically have high heating demands. The system 1 of the present invention is able to increase the temperature of the solar energy transfer flu id as it flows through the solar energy collector system 8 with 2.5°C degrees or more, e.g. 5°C or more (possibly even up to 10°C).

In the embodiment shown in Figure 1 the system 1 comprises a pump 16 and a three way valve 17 connected between the pump 16, the thermal energy storage system 20 and the solar

P6063948NL energy collector system 8. I.e. the solar energy collector system 8 is in thermal communication with the thermal energy storage system 20 via the three way valve 17. In this exemplary embodiment, the solar energy collector system 8 is a closed system having a flow F4 of solar energy transfer fluid, and in operation the output temperature T6 will be higher than the input temperature T5. The three way valve 17 acts as a mixing unit in cooperation with the pump 16 (with the combined flow F3) configured for exchanging thermal energy between the solar energy transfer fluid circulating through the solar energy collector system 8 and the thermal energy transfer fluid flowing through the TES system 20 with a flow F2. As indicated the heat exchanger 23 will increase the heat exchanger input temperature T3 to the heat exchanger output temperature T4..The flow amounts and mixing can be controlled by controlling the pump 16 and three way valve 17 (see also the description of Figure 4 below, using a control unit 24). The three way valve 17 may be controlled in percentage value K1 towards the thermal heat exchange system 20 (i.e. F2 = K1 x F3), resulting in the remainder of the flow F3 going towards the solar energy collector system 8 (i.e. F4= (100-K1) x F3). The total flow F3 is controlled by the power provided to the pump 16. This also allows various control schemes, based on measurement of one or more of the temperatures T1.. .T6 in the system 1.

In an embodiment, the solar energy collector system 8 comprises a separate cover structure 2 spanning across one or more of the at least one solar collector unit 3, as shown in Figure 2. In this embodiment the cover structure 2 spans across and above the one or more solar collecting units 3 so that cooling effects through e.g. cold atmospheric conditions (such as wind or precipitation) are greatly reduced. The cover structure 2 therefore allows for a significant increase in thermal efficiency of the system 1 by diminishing cooling effects by unfavourable atmospheric conditions. In an advantageous embodiment the cover structure 2 is transparent to solar radiation and exhibits minimal reflection of solar radiation. This is particularly effective in conditions where the ambient temperature is low.

When the solar energy collector system 8 is installed on a roof, the number of solar collector units 3 may well exceed 6, 8 or 10 solar collector units 3 and as such the system of the present invention allows for scalable deployment of the one or more solar collector units 3. The cover structure 2 can be scaled up as desired to span across a required number of collector units 3 and to provide sufficient enclosure thereof. Note that the cover structure 2 does not necessarily provide a hermitically sealed enclosure for the one or more solar collecting units 3, as long as sufficient isolation is provided from cold atmospheric influences.

In an embodiment the cover structure 2 is an arch based cover structure above one or more of the at least one solar collector unit 3. In this embodiment the one or more solar collector units 3 may, for example, be positioned flat on a roof and the arch based cover structure 2 shields the one or more collector units 3 from atmospheric influences.

In an advantageous embodiment, the cover structure 2 comprises a transparent plastic material, which provides sufficient strength and durability and reduces the risk of shatter on impact of e.g. hail. Examples of a transparent plastic material include, but are not limited to acrylate, poly methyl methacrylate (PMMA), polycarbonate, polyethylene, etc. To further increase the strength of

P6063948NL the cover structure 2, in an embodiment the cover structure 2 may have a corrugated surface. The corrugated surface of the cover structure 2 increases bending stiffness and further avoids damage during e.g. hail storms and the like.

In an embodiment, at least one solar collector unit 3 comprises a tubing based solar collector panel 3. The tubing based solar collector panel 3 allows for good circulation of the heat transfer fluid and allows for incoming solar radiation at various angles, thereby providing maximum thermal absorption throughout the day. In a further embodiment, the tubing based solar collector panel 3 comprises black tubing for maximum absorption of solar radiation. In even further embodiments, the tubing based solar collector panel 3 is made of polyethylene (PE) for excellent durability and service life as well as easy integration of the tubing based collector panel 3 with other parts of the solar energy collector system 8.

When the solar energy collector system 8 is installed on e.g. a roof, any thermal exchange between the solar energy collector system 8 and the roof surface itself should be minimized. To that end an embodiment is provided wherein at least one solar collector unit 3 is operationally mounted at a predetermined distance above the roof. In this embodiment the solar collector unit 3 comprises a minimized contact surface with the roof so that thermal exchange between the solar collector unit 3 and the roof is minimized. This embodiment may be envisaged as an embodiment wherein the solar collector unit 3 floats above the roof and thermal contact bridges are eliminated. In an exemplary embodiment the solar collector unit 3 may be supported through one or more cables for positioning the solar collector unit 3 at a predetermined distance above the roof.

If the roof onto which the solar energy collector system 8 is positioned in operation is provided with an isolating (top) layer, the solar collector units 3 may be positioned directly onto this isolating layer. Using the already present isolating layer will further increase the overall system efficiency, without requiring additional costs.

In an alternative embodiment the solar energy collector system 8 may further comprise a plurality of foundation blocks 6. Such foundation blocks 6 allow one or more solar collector units 3 to be positioned above the roof surface at a predetermined distance. The foundation blocks 6 may also be used to support the cover structure 2, and further components such as piping, as well.

As depicted in Figure 2, the solar energy collector system 8 may provide an enclosure by means of the cover structure 2 and having one or more feed lines 5 and return lines 4 for circulating heat transfer fluid through the one or more solar collector units 3. Foundation blocks 6 may be used to lift the one or more collector units 3 from the roof surface, thereby avoiding thermal contact bridges. Further structural elements 7 may be provided for the cover structure 2 so as to improve stability thereof. The cover structure 2 itself may in specific embodiments be made from one or more suitable transparent panels, e.g. corrugated transparent panels.

As depicted in Figure 3, in an embodiment the solar energy collector system 8 may further comprise piping elements 12-15 in communication with one or more solar collector units 3 of the solar energy collector system 8. The piping elements comprise a main feedline 12 and a main return line 15 for the heat transfer fluid. The main feedline 12 may branch into one or more panel input feed lines 13 each feeding a solar collector unit 3. In turn, the main return line 15 may branch into

P6063948NL one or more panel output return lines 14 each connected to an output of a solar collector unit 3. As a result, a parallel arrangement of a plurality of solar collector units 3 may be obtained for optimal absorption of solar radiation by the heat transfer fluid. In a further embodiment the solar energy collector system 8 may comprise a solar circulation pump 16a arranged for circulating the heat transfer fluid through one or more solar connecting units 3 as indicated in Figure 3.

The plurality of twelve solar collector units 3 as shown in the embodiment of Figure 3 is covered by the cover structure 2 as shown in Figure 2. Each solar collector unit 3 may again comprise a number of collector tubing groups (e.g. seven), connected to one panel input feed line 13 and one panel output return line 14. When having tubing groups of 0.33m wide and 3m length, this would provide a solar collector surface area of 12 x 7 x 3 x 0.33 = 84m².

To allow for improved circulation of the heat transfer fluid through the one or more collector units 3, the piping elements may comprise a main feedline 12 and a panel output return line 14, wherein the main feed line 12 is positioned higher than the panel output return line 14. This embodiment enables, for example, an inclined position of one or more solar collector units 3 for improving fluid flow from the main feed line 12 to the main return line 15. The inclined position may be achieved, for example, by installing the solar energy collector system 8 on a flat roof and providing an inclining structure on which the one or more solar collector units 3 can be mounted, wherein the cover structure 2 encloses the inclined solar collector units 3. Alternatively, a sloped roof may be used for placement of one or more solar collector units 3, thereby utilizing an existing de-watering inclination provided by the roof.

The system of the present invention may comprise various electronic components, such as electrical pumping elements, electrical valves, electrical control circuits and the like. In an advantageous embodiment the system 1 further comprises one or more photovoltaic (PV) modules 19 in addition to the one or more solar collector units 3, wherein the one or more photovoltaic (PV) modules 19 are arranged to provide the system 1 with electrical operating power. This is shown in the schematic diagram of Figure 4, wherein the PV modules 19 provides operating power to a control unit 24, as well as to pump 16 and three way valve 17. The control unit 24 is also arranged to control the pump 16, three way valve 17 and heat exchanger 23, as indicated by the dashed lines This embodiment, as shown in Figure 1, allows the PV modules 19 to power the various electronics of the system 1 (pumps, valves etc.). In an embodiment, the PV modules 19 are arrange to provide the solar energy collector system 8 and/or the thermal energy storage system (TES) 20 with electrical power.

In an advantageous embodiment, the one or more photovoltaic modules 19 are operationally positioned on a part of the roof not occupied by the solar energy collector system 8. This embodiment allows efficient use of the roof and an optimal combination for maximizing usage of the roof surface.

The above described exemplary embodiments can be summarized by the following (dependent) embodiments:

Embodiment 1. System for supplying energy to a building with a roof, such as a green house, comprising

P6063948NL a thermal energy storage system (20) for providing heat and/or cooling to the building, having a heat storage well, a cold storage well, and a thermal energy transfer system (23) transferring thermal energy from the heat storage well and/or cold storage well using a thermal energy transfer fluid, further comprising a solar energy collector system (8) based on circulation of a solar energy transfer fluid having at least one solar collector unit (3), which during operation is exposed to solar radiation and arranged to transform the solar radiation to thermal energy in the solar energy transfer fluid, wherein the solar energy collector system (8) is integrated with the thermal energy storage system (20) by using the thermal energy transfer fluid as the solar energy transfer fluid.

Embodiment 2. System according to embodiment 1, wherein the solar energy collector system (8) comprises a separate cover structure (2) spanning across one or more of the at least one solar collector unit (3).

Embodiment 3. System according to embodiment 2, wherein the cover structure (2) is an arch based construction above one or more of the at least one solar collector units (3).

Embodiment 4. System according to embodiment 2 or 3, wherein the cover structure (2) comprises a transparent plastic material.

Embodiment 5. System according to any one of embodiments 2-4, wherein the cover structure (2) has a corrugated surface.

Embodiment 6. System according to any one of embodiments 1-5, wherein the at least one solar collector unit (3) comprises a tubing based solar collector panel.

Embodiment 7. System according to any one of embodiments 1-6, wherein the at least one solar collector unit (3) is operationally mounted at a predetermined distance above the roof. Embodiments. System according to any one of embodiments 1-7, wherein the solar energy collector system (8) further comprises a plurality of foundation blocks (6).

Embodiment 9. System according to any one of embodiments 1-8, wherein the system (1) comprises a pump (16) and a three way valve (17) connected between the pump (16), the thermal energy storage system (20) and the solar energy collector system (8), and a control unit (24) connected to the pump (16) and the three way valve (17) for controlling the flow of the thermal energy transfer fluid.

Embodiment 10. System according to embodiment 9, wherein the solar energy collector system (8) further comprises piping elements (12-15) in communication with the at least one solar collector unit (3), the piping elements (12-15) comprising a main feed line (12) and a panel output return line (14), wherein the main feed line (12) is positioned higher than the panel output return line (14). Embodiment 11. System according to anyone of embodiments 1-10, wherein the system (1) further comprises one or more photovoltaic modules (19), arranged to provide the system (1) with electrical operating power.

Embodiment 12. System according to embodiment 11, wherein the one or more photovoltaic modules (19) are operationally positioned on a part of the roof not occupied by the solar energy collector system (8).

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The present invention has been described above with reference to a number of exemplary embodiments as shown in the drawings. Modifications and alternative implementations of some parts or elements are possible, and are included in the scope of protection as defined in the appended claims.

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Claims

CONCLUSIESCONCLUSIONS

1. Systeem voor het voorzien van energie aan een gebouw met een dak, zoals een kas, omvattend een systeem voor opslag van thermische energie (20) voor het verschaffen van warmte en/of koeling aan het gebouw, met een warmteopslagbron (21), een koudeopslagbron (22), en een thermische-energieoverdrachtsysteem (23) voor het overdragen van thermische energie vanuit de warmteopslagbron (21) en/of koudeopslagbron (22) met gebruik van een thermischeenergieoverdrachtfluïdum, verder omvattend een zonne-energiecollectorsysteem (8) die gebaseerd is op circulatie van een zonneenergieoverdrachtfluïdum met ten minste één zonnecollectoreenheid (3), die tijdens bedrijf is blootgesteld aan zonnestraling en is ingericht om de zonnestraling om te zetten in thermische energy in het zonneenergieoverdrachtfluïdum, waarbij het zonne-energiecollectorsysteem (8) is geïntegreerd met het systeem voor opslag van thermische energie (20) door het gebruiken van het thermische-energieoverdrachtfluïdum als het zonneenergieoverdrachtfluïdum.A system for supplying energy to a building with a roof, such as a greenhouse, comprising a thermal energy storage system (20) for providing heat and / or cooling to the building, with a heat storage source (21), a cold storage source (22), and a thermal energy transfer system (23) for transferring thermal energy from the heat storage source (21) and / or cold storage source (22) using a thermal energy transfer fluid, further comprising a solar energy collector system (8) based on is for circulation of a solar energy transfer fluid with at least one solar collector unit (3) exposed to solar radiation during operation and is adapted to convert the solar radiation into thermal energy in the solar energy transfer fluid, the solar energy collector system (8) being integrated with the thermal energy storage system (20) using the thermal energy transfer fluid as the z non-energy transfer fluid.

2. Systeem volgens conclusie 1, waarbij het zonne-energiecollectorsysteem (8) een afzonderlijke afdekstructuur (2) omvat die zich uitstrekt over één of meer van de ten minste ene zonnecollectoreenheid (3).A system according to claim 1, wherein the solar energy collector system (8) comprises a separate cover structure (2) that extends over one or more of the at least one solar collector unit (3).

3. Systeem volgens conclusie 2, waarbij de afdekstructuur (2) een op een boog gebaseerde constructie is boven één of meer van de ten minste ene zonnecollectoreenheid (3).The system of claim 2, wherein the cover structure (2) is an arc-based structure above one or more of the at least one solar collector unit (3).

4. Systeem volgens conclusie 2 of 3, waarbij de afdekstructuur (2) een transparant kunststofmateriaal omvat.A system according to claim 2 or 3, wherein the cover structure (2) comprises a transparent plastic material.

5. Systeem volgens één van de conclusies 2-4, waarbij de afdekstructuur (2) een gegolfd oppervlak heeft.The system of any one of claims 2-4, wherein the cover structure (2) has a corrugated surface.

6. Systeem volgens één van de conclusies 1-5, waarbij de ten minste ene zonnecollectoreenheid (3) een op buizen gebaseerd zonnecollectorpaneel omvat.The system of any one of claims 1-5, wherein the at least one solar collector unit (3) comprises a tube-based solar collector panel.

7. Systeem volgens één van de conclusies 1-6, waarbij de ten minste ene zonnecollectoreenheid (3) tijdens bedrijf gemonteerd is op een vooraf bepaalde afstand boven het dak.The system according to any of claims 1-6, wherein the at least one solar collector unit (3) is mounted at a predetermined distance above the roof during operation.

8. Systeem volgens één van de conclusies 1-7, waarbij het zonne-energiecollectorsysteem (8) verder een veelvoud funderingsblokken (6) omvat.The system of any one of claims 1-7, wherein the solar energy collector system (8) further comprises a plurality of foundation blocks (6).

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9. Systeem volgens één van de conclusies 1-8, waarbij het systeem (1) een pomp (16) en een driewegklep (17) omvat die verbonden is tussen de pomp (16), het systeem voor opslag van thermische energie (20) en het zonne-energiecollectorsysteem (8), en een besturingseenheid (24) die verbonden is met de pomp (16) en de driewegklep (17) voor het besturen van de stroming vanThe system of any one of claims 1-8, wherein the system (1) comprises a pump (16) and a three-way valve (17) connected between the pump (16), the thermal energy storage system (20) and the solar collector system (8), and a control unit (24) connected to the pump (16) and the three-way valve (17) for controlling the flow of

5 de thermische-energieoverdrachtfluïdum.5 the thermal energy transfer fluid.

10. Systeem volgens conclusie 9, waarbij het zonne-energiecollectorsysteem (8) verder buiselementen (12-15) omvat die in verbinding staan met de ten minste ene zonnecollectoreenheid (3), waarbij de buiselementen (12-15) een hoofdaanvoerleiding (12) en eenThe system of claim 9, wherein the solar energy collector system (8) further comprises tubular elements (12-15) communicating with the at least one solar collector unit (3), the tubular elements (12-15) having a main supply line (12) and a

10 paneeluitvoerretourleiding (14) omvatten, waarbij de hoofdaanvoerleiding (12) hoger is geplaatst dan de paneeluitvoerretourleiding (14).10 include panel output return line (14), wherein the main supply line (12) is positioned higher than the panel output return line (14).

11. Systeem volgens één van de conclusies 1-10, waarbij het systeem (1) verder één of meer fotovoltaïsche modules (19) omvat, die zijn ingericht om het systeem (1) te voorzien van elektrischThe system of any one of claims 1-10, wherein the system (1) further comprises one or more photovoltaic modules (19) adapted to provide the system (1) with electrical

15 bedrijfsvermogen.15 operating power.

12. Systeem volgens conclusie 11, waarbij de één of meer fotovoltaïsche modules (19) tijdens bedrijf zijn geplaatst op een deel van het dak dat niet bezet is door het zonneenergiecollectorsysteem (8).The system according to claim 11, wherein the one or more photovoltaic modules (19) are placed during operation on a part of the roof that is not occupied by the solar energy collector system (8).

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