JP7359371B2 - roof structure - Google Patents

Description

The present invention relates to a roof structure having a heat recovery system using roof-integrated solar panels.

In recent years, as houses and buildings have become more airtight and highly insulated, there has been a demand for effective use of renewable energy such as solar heat and active use of solar power generation on an independent basis. In particular, given the small size of Japan's land and housing, it is extremely difficult to efficiently utilize solar heat and solar power generation at the same time, so advanced renewable energy utilization technology is required.

For example, Patent Document 1 discloses a whole-house air conditioning system that takes warm outside air between the solar panel and the roof into the house from the center back of the solar panel.

Furthermore, in Patent Document 2, a switching mechanism for switching between a reflective section and an absorbing section is installed on the roof, and a light-transmissive solar cell is placed on top of the switching mechanism, and indoor air is flowed between the switching mechanisms.The system uses the same principle as the solar chimney to collect solar heat. Ventilation is being used.

JP 2017-122564: Patent No. 6303105 JP2017-218825A

Patent Document 1 uses solar power generation and air heated by solar heat indoors, and can be said to make efficient use of sunlight. However, the outside air passing under the solar panels is only heated at a distance of half the length of the eaves from the solar panel ridge, so it cannot be said that enough solar heat is recovered.

Although Patent Document 2 uses solar heat in addition to sunlight, the solar heat is used for ventilation and does not directly return the heat to people living indoors. do not have.

The present invention was conceived in view of the above-mentioned problems, and is a heat recovery system that can generate solar power and at the same time directly return the heat obtained from solar radiation to people living indoors. The present invention provides a roof structure having a system.

More specifically, the roof structure according to the present invention includes:
a bottom plate disposed above the support member;
disposed on the bottom plate and having peaks and valleys;
An indoor ventilation opening is provided at the ridge side end of either the peak or the valley,
An outside air intake is provided at the other ridge side end of the peak and valley,
The peak portion and the valley portion include a folded plate material having a common space at the eave side end;
A solar panel installed on the folded plate material,
a chamber connected to the indoor air outlet;
It is characterized in that it has a blower fan connected to the chamber.

The roof structure according to the present invention has a structure in which so-called folded plates are sandwiched between a bottom plate and a solar panel, and by rotating a blower fan in a direction to suck outside air indoors, the trough at the edge of the ridge is The outside air is taken in from the ridge (or ridge), passed under the solar panel, turned around the ridge (or trough) at the eaves, passed under the solar panel again, and then brought into the room from the ridge. As the outside air is taken in, it is sufficiently warmed as it travels back and forth under the solar panels, and even cold outside air can be used as warm air for indoor heating or water heating.

In addition, when using an air conditioner to cool the indoor area in the summer, the blower fan is operated to blow air from the indoor side to the outdoor area, and the cool indoor air is passed under the solar panels and sent outdoors from the outside air intake. By discharging it, the solar panels can be cooled and the power generation efficiency of the solar panels can be increased. In addition, by discharging indoor air outdoors in this way, it is also possible to prevent hot outside air from flowing into the room and to prevent cross-flow heat from entering the room from the roof structure.

FIG. 1 is a perspective view of a roof structure according to the present invention. It is a diagram of the roof structure viewed diagonally from below. 2 is a diagram showing a cross section taken along line AA in FIG. 1. FIG. 2 is a diagram showing a cross section taken along line BB in FIG. 1. FIG. FIG. 2 is a diagram in which a part of FIG. 1 is removed to visualize the inside. FIG. 2 is a plan view of FIG. 1 with the solar panel removed. It is a perspective view of the roof structure when the direction of an air path is different. It is a sketch of a roof structure produced for an example. It is a figure showing the installation situation of the roof structure of an example. It is a diagram of experimental results showing that the surface temperature of a solar panel can be lowered by releasing cooled air from the indoor side toward the outdoors.

The roof structure according to the present invention will be described below with reference to drawings and examples. In addition, the following description illustrates one embodiment and one example of the present invention, and the present invention is not limited to the following description. The following description can be modified without departing from the spirit of the present invention.

FIG. 1 is a perspective view of a roof structure according to the present invention. FIG. 2 is a diagram of FIG. 1 viewed diagonally from below. The roof structure 1 according to the present invention may be the entire roof or a part of the roof.

It is desirable that the roof structure 1 be provided in the north-south direction, and be provided so as to be inclined from the horizontal to higher from the south side to the north side (angle θ in FIG. 1). The north side of the roof structure 1 is called the ridge side, the south side is called the eave side, the ridge side end is called the ridge side end Rt, and the eave side end is called the eave side end Et. A ridge side end vertical wall 30 is formed at the ridge side end Rt, and an eave side end wall 34 is formed at the eave side end Et.

The roof structure 1 includes a solar panel 10, a folded plate material 12, a bottom plate 14, a chamber 16, a duct 18, and a blower fan 20. Note that the roof structure 1 is supported by a support member (not shown). The support member can be preferably made of wood or metal, and may be a part of the structure or skeleton of a building. The supporting member may be a so-called pillar supporting the roof, or a wall if the roof is supported by a wall.

The bottom plate 14 is a planar member fixed on the support member. The material is not particularly limited, but any material is desirable as long as it has a heat insulating effect. The folded plate material 12 is a plate material having an uneven cross section, which is composed of peaks 12m and valleys 12v. Note that FIG. 4 shows a cross section taken along line BB in FIG. The bottom plate 14 closes the lower part of the mountain portion 12m. The space formed by the bottom plate 14 and the mountain portion 12m is called an ascending path 46.

Referring again to FIG. A solar panel 10 is installed on the folded plate material 12. As shown in the cross section of FIG. 4, the solar panel 10 closes the upper part of the valley 12v of the folded plate material 12. The space formed by the solar panel 10 and the valley portion 12v is called a descending path 44. The ascending passage 46 and the descending passage 44 may simply be referred to as air passages. Note that the width of the top of the ridge portion 12m is represented by 12mw, the width of the bottom of the trough portion 12v is represented by 12vw, the depth of the crest and valley is represented by 12d, and the pitch of the ridge and valley is represented by 12p.

Referring again to FIG. The ridge-side end 10Rt of the solar panel 10 ends closer to the eaves than the ridge-side end 12Rt of the folded plate material 12. The gap between the ridge side end Rt and the ridge side end 10Rt of the solar panel 10 is called a gap 10G. The peak portions 12m and the valley portions 12v of the folded plate material 12 are exposed in the gap 10G.

Since the downward passage 44 is formed between the valley part 12v and the solar panel 10, the valley part 12v exposed at the gap 10G becomes an opening connected to the downward passage 44. This opening is called an outside air intake 40. In addition, at the ridge-side end 12Rt of the folded plate material 12, the mountain portion 12m is closed by a ridge-side end vertical wall 30 provided at the ridge-side end Rt.

Reference is now made to FIGS. 2 and 3. FIG. 2 is a perspective view of the roof structure 1 viewed from below the ridge side (north side), and FIG. 3 is a cross section taken along line AA in FIG. The AA cross section is a diagram cut at the peak 12m of the folded plate material 12. A rising path 46 is formed between the mountain portion 12m and the bottom plate 14. A mountain portion 12m at the ridge side end 12Rt of the folded plate material 12 is closed by a ridge side end vertical wall 30. Further, an opening is provided near the ridge side end Rt of the bottom plate 14 to allow the bottom plate 14 to exit downward. This opening is called an indoor air outlet 42.

A chamber 16 is provided below the ridge side end Rt of the roof structure 1 across the width direction of the roof structure 1. The chamber 16 has an internal space that is open at the top and connected to the bottom plate 14, and closed at the bottom and sides. The chamber 16 communicates with all indoor ventilation ports 42. Further, the chamber 16 also communicates with the duct 18. A blower fan 20 is arranged in the duct 18.

From the viewpoint of effective use of solar heat, the blower fan 20 is operated as an intake fan that blows air from outdoors to indoors (in this specification, "indoor" is used synonymously with "indoor") in winter. On the other hand, in summer, the temperature of the solar panel becomes excessively high, reducing the efficiency of photoelectric conversion. Further, even if the room is cooled by an air conditioner or the like, hot outside air may enter the room through the air passage of the roof structure 1.

Therefore, the blower fan 20 may be operated as an exhaust fan so that the cool indoor air cooled by air conditioning or the relatively low-temperature air in the attic flows from indoors to outdoors. In this way, exhausting indoor air outdoors through the air path prevents the intrusion of outside air and the intrusion of heat passing through from the high-temperature roof structure, and also contributes to cooling the solar panels.

FIG. 5 is a diagram illustrating the interior of FIG. 1 with some parts omitted. The ridge side end 12Rt of the folded plate material 12 is in contact with the ridge side end vertical wall 30, but the eave side end 12Et of the folded plate material 12 does not extend to the eave side end Et. As for the roof structure 1, the eave side end Et is closed by an eave side end wall 34.

The eave side end wall 34 is formed of an eave side end vertical wall 34a, an eave side end upper wall 34b, and an eave side end side wall 34s, and forms a closed space together with the bottom plate 14. That is, a space surrounded by the eave side end wall 34 and the bottom plate 14 is formed. This space communicates with both the descending path 44 and the ascending path 46. This space is called a common space 36.

Next, the operation of the roof structure 1 according to the present invention will be explained. Referring to FIG. 2, when the blower fan 20 is operated to send air from the outdoors to the indoor side, and the air is sucked indoors through the air passage, the chamber 16, the ascending passage 46, the common space 36, and the descending passage 44 (see FIG. (or see FIG. 6), and the outside air intake 40, which in turn becomes negative pressure. Therefore, outside air is drawn indoors following the above path in reverse.

FIG. 6 is a plan view of the roof structure 1 with the solar panel 10 partially omitted. The outside air CW sucked in from the outside air intake 40 passes through the downward path 44 and flows toward the eaves. At this time, the temperature rises due to the heat from the heated solar panel 10, and becomes warm outside air Wm. When the outside warm air Wm reaches the common space 36, it ascends from the common space 36 through the ascending path 46. At this time, heat is received from the solar panel 10 again and the temperature rises, becoming warm air WM.

The warm air WM flows into the chamber 16 from the indoor air outlet 42 on the ridge end Rt side (see FIG. 3). From the chamber 16, it is sent indoors via a duct 18.

Even when the outside air temperature is low in this way, by moving the lower side of the solar panel 10 back and forth from the ridge side to the eaves side, heat exchange is performed between the solar panel 10 and the warm air. It can be taken indoors. In other words, cooling the solar panel 10 and recovering heat can be performed simultaneously.

On the other hand, when the outside temperature and sunlight are strong, such as during summer, and the room is cooled by an air conditioner or the like, the blower fan 20 may be operated as an exhaust fan that sends air from the room to the outdoors. In this case, the chamber 16, the ascending passage 46, the common space 36, and the descending passage 44 (see FIG. 5 or 6) become positive pressure in this order, and the cold air inside the room is discharged outdoors following the above-mentioned path.

At this time, the solar panel 10 can be cooled by circulating indoor air cooled by a cooler or the like on the lower side of the solar panel 10 from the ridge side to the eaves side. The efficiency of the solar panel 10 during heating decreases, so if the solar panel 10 can be cooled, the efficiency of the heated solar panel 10 in the summer can be improved.

Furthermore, by discharging indoor air outdoors, it is also possible to prevent high-temperature outside air from leaking into the room.

Note that whether the blower fan 20 is operated to draw air from the outdoors to the indoor side or to discharge air from the indoor side to the outdoor side may be switched using a changeover switch or the like. Further, as the ventilation fan 20, a suction fan and a discharge fan may be provided separately so that they can be used properly.

In the above explanation, the blower fan 20 was illustrated as being connected to the duct 18, but as long as it exerts a suction action (or discharge action) on the duct 18 indoors, it may be used other than the above explanation. It may be a configuration. For example, if a blower fan of a heating and cooling device placed indoors creates a negative pressure in the duct 18, the blower fan of the heating device can be interpreted as the blower fan 20 used for air intake in the present invention. Further, there may be some gap between the folded plate material 12 and the solar panel 10 as long as the descending path 44 and the ascending path 46 are substantially ensured. This is because when installing the solar panel 10 on the folded plate material 12, a gap equal to the thickness of the mounting fittings may be required.

In the present invention, outside air is reciprocated between the ridge side end Rt and the eave side end Et to increase the temperature of the cold outside air and collect heat. In the above explanation, outside air is taken in from the valley 12v, lowered to the eave side edge Et, passed through the peak 12m, raised to the ridge edge Rt, and reciprocated. However, when the outside air is reciprocated, the peak portion 12m may be lowered from the ridge side end Rt to the eave side end Et, and the valley portion 12v may be raised from the eave side end Et to the ridge side end Rt.

FIG. 7 shows an example of the roof structure 2 with such a wind path. The configurations such as the solar panel 10, folded plate material 12, bottom plate 14, chamber 16, and blower fan 20 are the same as in FIGS. 1 to 5.

The roof structure 2 is provided with a gap plate 10GB that closes the gap 10G. A through hole 10GBh is formed in the gap plate 10GB. This corresponds to the outside air intake 40 in FIG.

The gap plate 10GB abuts without a gap with the peak portion 12m of the folded plate material 12 exposed in the gap 10G. The through hole 10GBh is provided at a position that coincides with the through hole 12mh provided in the peak portion 12m.

Further, in the valley portion 12v of the folded plate material 12, a through hole 12vh is provided at a position that coincides with the indoor ventilation port 42 at the upper part of the chamber 16.

In the roof structure 2 having the above configuration, when the blower fan 20 is operated in the direction of sucking outside air into the room, the outside air CW is sucked through the through hole 10GBh of the gap plate 10GB. The outside air CW is taken into the peak part 12m through the through hole 12mh of the peak part 12m, and moves down the roof structure 2 from the ridge side edge Rt toward the eave side edge Et.

The outside air CW turned back in the common space ascends the roof structure 2 along the valley portion 12v from the eave side end Et to the ridge side end Rt. The air is then collected into the chamber 16 from the indoor air outlet 42. Therefore, in the case of the roof structure 2, the descending path is the mountain portion 12m, and the ascending path is the valley portion 12v. In this way, even if the direction of the air passage is changed, the heat collecting effect of the roof structure of the present invention remains the same.

That is, in the present invention, the outside air intake 40 that takes outside air into the roof structure 2 from outside and the indoor air outlet 42 that reciprocates inside the roof structure 2 and takes in the indoor side (chamber 16) are connected to the pile of folded plate materials 12. It can be provided on either side of the portion 12m and the valley portion 12v.

FIG. 8 shows a roof structure 1 produced as a demonstration experiment. FIG. 8(a) is a side view, and FIG. 8(b) is a plan view. A solar panel 10 with a length 10L of 1020 mm and a width 10W of 1670 mm was used. A folded plate material 12 was placed under the solar panel 10. In addition, in FIG. 8, the folded plate material 12 is not visible because the side surface is closed. In the folded plate material 12, the peak width of the peak portion 12m is 12 mw (the bottom width 12vw of the valley portion 12v is 108 mm), the width is 21 mm, the depth 12d of the peak and valley is 30 mm, and the pitch of the peak and valley of 12p is 163 mm (see FIG. 4).

A gap cover 50 is provided to stabilize the temperature of the air passing through the gap 10G. The gap cover 50 airtightly covers the entire gap 10G. The gap cover 50 is provided with a passage port 50a for air to enter and exit the gap 10G. The inner diameter of the passage port 50a was 100 mm. The chamber 16 was provided with a duct 18 having a diameter of 100 mm. All the air passing through the passage port 50a passes through the gap 10G.

FIG. 9 shows how the roof structure 1 is installed. FIG. 9A shows a case where solar heat is recovered, and FIG. 9B shows a case where the solar panel 10 is cooled. In FIGS. 9A and 9B, the directions of air flow (indicated by arrows) are reversed. The roof structure 1 was fixed with a frame (support body) not shown so that the inclination angle θ was 21.8 degrees facing south.

The passage port 50a was connected from the duct 18 with a heat insulating duct hose 54. A blower fan 20 and an air cooling device 52 are connected to the duct hose 54 in the middle. An anemometer 18k was placed on the duct hose 54. The air volume was calculated from the wind speed and the inner diameter of the duct hose 54. Further, a thermometer 50k and a thermometer 16k are arranged at the passage port 50a and the duct 18, so that the air temperature passing through the passage port 50a and the duct 18 can be measured. In addition, a pyranometer was arranged beside the roof structure 1 in parallel with the solar panel, so that the amount of solar radiation on the slope could be measured. Moreover, in the case of FIG.9(b), the thermometer 10k which measures the surface temperature of the solar panel 10 was arrange|positioned.

[Solar heat recovery experiment]
The blower fan 20 was operated in the direction of suction from the duct 18, and air was continuously flowed in the direction shown in FIG. 9(a). The amount of solar radiation, the temperature at the passage port 50a, the temperature at the duct 18, and the air volume were measured at 10 second intervals. The measurements were taken on March 6, 2020. The measurement results are shown in Table 1. The standard heat collection efficiency η and the heat collection amount Q were calculated using the following equations (1) and (2) according to JIS A 4112 (2011). The daily heat collection efficiency was calculated as "total heat collection amount/total hourly solar radiation amount".

Note that d ₀ , d ₁ : coefficients determined by the least squares method from the experimental results; in this case, d ₀ =0.2819 and d ₁ =-7.8016.
Δθ': difference between the test specimen inlet air temperature and the ambient temperature, K, set to 10K according to JIS A 4112.
I: Hourly solar radiation, W/m ² , values shown in Table 1 according to JIS A 4112.

Referring to Table 1, the roof structure 1 according to the present invention achieved a very high solar heat collection efficiency of 15.1%.

[Solar panel cooling experiment]
The measurements were taken on June 9, 2021. The air cooling device 52 cools the air from the passage port 50a and sends it to the duct 18. The measurement results of the solar panel temperature Tp, inlet temperature Ti (air temperature of the duct 18), outlet temperature To (air temperature of the passage port 50a), outside temperature Te, total solar radiation on the slope Sr, and air volume Av in the duct are shown in FIG. .

Referring to FIG. 10, from 9 a.m. to 11 a.m., the blower fan 20 and the air cooling device 52 remained stopped. At this time, the temperature at the passage port 50a was 50°C to 54°C. On the other hand, the temperature in duct 18 was between 30°C and 31°C.

Only the ventilation fan 20 was operated from 11:00 a.m. to 11:55 a.m. When the blower fan 20 was operated, the temperature at the passage port 50a once dropped to 32°C, and then rose again to 50°C. The temperature in the duct 18 rose to 50° C. or more immediately after the blower fan 20 was started. Although the temperature at the passage port 50a temporarily decreased due to the flow of cold air accumulated in the duct hose 54, it was thought that this was because the temperature of the air remained constant while the air circulated.

The air cooling device 52 was operated together with the blower fan 20 from 11:55 a.m. to 1:30 p.m. This time period was the time with the highest amount of solar radiation on that day. The temperature at the passage port 50a dropped to about 45°C, and the temperature at the duct 18 dropped to about 30°C.

The temperature in the duct 18 is thought to have dropped to about 30° C. because the air cooled by the air cooling device 52 flows therethrough. On the other hand, the temperature at the passage port 50a becomes high because the passage passes through the roof structure 1, which has a high temperature. In other words, the solar panel 10 is brought into contact with cold air due to the air at the temperature of the duct 18 .

Due to this cooling effect, the surface temperature of the solar panel 10 decreased from 68°C to approximately 64°C. The power generation efficiency of solar panels decreases as the solar panel temperature increases. Generally, a temperature increase of 1° C. (in the case of a crystalline solar power generation element) causes a decrease in power generation efficiency of 0.4%. Therefore, it has been found that if the surface temperature of the solar panel is lowered by about 4 to 6 degrees Celsius, the power generation efficiency of the solar panel can be expected to improve by 1.6 to 2.4%.

INDUSTRIAL APPLICATION This invention can be suitably utilized for the roof of a building.

1, 2 Roof structure 10 Solar panel 10Rt Ridge side end 10G of solar panel 10 Gap 10GB Gap plate 10GBh Through hole 12 Folded plate material 12m Peak portion 12mw Peak width 12mh Through hole 12v Valley portion 12vw Valley bottom width 12vh Through hole 12p Pitch 12d (Mountain and valley) depth 12Rt Ridge side end 12Et of folded plate material 12 Eave side end 14 of folded plate material 12 Bottom plate 16 Chamber 18 Duct 18k Anemometer 20 Ventilation fan 30 Ridge side end vertical wall 34 Eave side end wall 34a Eave side end vertical Wall 34b Eave side end upper wall 34s Eave side end side wall 36 Common space 40 Outside air intake 42 Indoor ventilation port 44 Downward path 46 Upward path 50 Gap cover 50a Passing port 52 Air cooling device 54 Duct hose 50k, 16k, 10k Thermometer Rt Ridge side end Et Eave side end CW Outside air Wm Outside warm air WM Warm air

Claims (4)

a bottom plate disposed above the support member;
disposed on the bottom plate and having peaks and valleys;
An indoor ventilation opening is provided at the ridge side end of either the peak or the valley,
An outside air intake is provided at the other ridge side end of the peak and valley,
The peak portion and the valley portion include a folded plate material having a common space at the eave side end;
A solar panel installed on the folded plate material,
a chamber connected to the indoor air outlet;
A roof structure comprising a blower fan connected to the chamber. The indoor air outlet is provided at the ridge side end of the mountain part,
2. The roof structure according to claim 1, wherein the outside air intake is provided at a ridge side end of the valley. 3. The roof structure according to claim 1, wherein the blower fan is a fan that blows air from outdoors to indoors. 3. The roof structure according to claim 1, wherein the blower fan is a fan that blows air from indoors to outdoors.