WO2011047679A1

WO2011047679A1 - Air heating solar panel

Info

Publication number: WO2011047679A1
Application number: PCT/DK2010/000136
Authority: WO
Inventors: Palle Kerdil
Original assignee: Ans Solvarme; Dlc Aps; Kw Promotion Llc
Priority date: 2009-10-19
Filing date: 2010-10-15
Publication date: 2011-04-28
Also published as: DK201000017A

Abstract

The invention relates to an air solar panel to heat the air. The air solar panel comprises a frame fitted with a transparent front and a rear comprising at least one reflector plate, and a number vacuum tubes, where each vacuum tube encloses at least one inlet pipe, the vacuum tubes ar closed at one end. The inlet pipes provide the relatively cold air from the outside into the air so panel through one or more openings into the vacuum tubes, the air coming out of the inlet pip run along the inside surface of the vacuum tubes and then along the outside surface of the vacuum tubes. A fan is used to blow the heated air out of the air solar panel.

Description

Air Heating Solar Panel

The present invention relates to an air solar panel that can be used to heating the air to be led into a room by a fan. The background of the invention

Along with the recognition that the amount of fossil fuel reserves is very limited, focus has been on the use of alternative and renewable energy sources including solar energy.

The interest in renewable energy has increased dramatically after the focus has been set on the environmental changes caused by human.

Here carbon dioxide, C02 produced in large quantities by the burning of organic materials, especially fossil fuels, has been touted as the biggest culprit. Because the gas, carbon dioxide increases the greenhouse effect.

According to the UN climate panel, IPCC, the increase in greenhouse gases in the atmosphere will lead to a rise in the temperature of between 1.8 and 5.8 degrees over the next 100 year. This will in particular have implications for the sea level, which will rise somewhere between 0.2 and 0.6 meters over the next 100 years.

Precipitation on land will also increase, overall. It will differ from area to area, so that some places will experience less rainfall and elsewhere significantly higher amounts of rain. The trend will be that dry areas will become drier while wet areas will become wetter.

Therefore there is a great need for significant innovations in the use of solar energy - including the use of solar energy for heating rooms.

To save on cost of heating rates and to show respect for the environment the houses in Denmark are isolated more and more. But an increasing in isolation may cause a humid indoor climate, and this creates a need for ventilation to remove the moist air. The present invention concerns an air solar panel which both can be used for residential heating and ventilation of buildings under the exclusive use of solar energy. In spite of approaches and devices for converting energy from the sunlight which irradiates the earth to heat and/or electricity has been known for decades, the air solar panel according to the present invention has demonstrated that the effective efficiency can be increased dramatically in compared to known air solar panels. More specific the invention concerns an air solar panel for heating air, comprising a frame, fitted with a transparent front and a rear which is fitted with at least one reflector plate and a number of vacuum tube, which encloses at least one inlet, which inlet is provided to relatively cold air outside the frame through one or more openings, preferably after the first air has been filtered for dust particles, etc.. The heated air from the air solar panel is led into the room to be heated through an opening on the back of air solar panel. Furthermore, the invention includes an electric panel and a fan, what fan would benefit from receiving its power from the electric panel.

Known technique

It is well known both to use solar panels to heat water and air.

When heating water frost-proof liquid is used where said liquid is heated in the solar panel and delivers the accumulated heat to the water in a hot water tank. The hot water in the hot water tank can be used directly as hot water from taps and/or the hot water can used as a heat source for a central heating system for domestic heating. Many examples of the use of solar panels to heat the air are know, where the heated air are used for ventilation or heating. This application can either be direct or through a heat exchanger.

From the French patent application FR 2,500,036, is known a typical example of a simple solar panel to heat the air. This panel has a transparent front panel and a heat absorbing plate mounted on the rear panel where the heat-absorbing plate on the rear panel is insulated against the back wall. In the bottom of the solar panel is an intake of cold air. The cold air enters from the front panel and the heat-absorbing plate mounted on the rear panel, and here is the cold air is heated before passing to the outlet hole in the top of the solar panel.

From the U.S. patent No. 4,054,124 is known a more sophisticated solar panel, where a perforated heat absorbing element was inserted between the transparent front panel and the insulated back panel. The air from the environment entering solar panel on one side and from here carried the air into the space between the front panel and the heat absorbing panel, through the perforation where the air is heated, and through the cavity between the heat accumulating panel and the insulated back panel. This produces a significantly greater heat transfer between air and the heated absorbent element than what example can be achieved by the invention described in FR 2,500,036.

There are several examples of the use of vacuum tubes in the solar air collectors, including the Chinese patent specifications: CN 2653381 Y Y CN287221 1 and CN201 199096Y, each for a use of vacuum tubes for air solar panels.

But common to the known air solar panels that use vacuum tubes, however, the limited use of solar energy, because the partially heated air is diverted past the outside of the vacuum tubes before the example used for space heating.

Compared with traditional flat solar collector vacuum tubes has generally at least three major advantages. Benefits both relevant for the solar collectors used for water heating and the solar panels used to heat the air:

Because of the vacuum in the tubes, there is established a very effective insulator, therefore the heat loss from the absorber to the cover layer is reduced considerably compared to the flat plate collectors. This construction therefore has the

consequence that vacuum tube solar panels produces proportionately more heat in weather with very diffuse radiation. The selective coating on the absorber is protected from moisture. This fact implies that the absorber maintains its absorptive properties, unlike traditional flat plate collectors, where the properties of the selective coating deteriorate with time. The shape of the tubes causes the solar radiation at high angles utilized better than flat plate collectors.

The aforementioned advantages of the vacuum tube solar collectors makes them especially suited to the Danish climate where the heat loss from the traditional flat plate collectors in the winter months causes the solar collectors' for long periods does not produce any heat at all.

The Technical University of Denmark, Department of Buildings and Energy has completed a research project in 1997 and 1998 concerning the usefulness of water collectors, to clarify the usefulness of the vacuum tube collectors compared to traditional flat plate collectors. http://nive2.dk/index.php?option=com docman&task=doc view&gid=14&tmpl=comp onent&format=raw&ltemid=69 The results from this research showed that the usefulness of the available solar energy per area unit is significantly larger for vacuum tube panels than for conventional flat solar panels.

In the experiments a Chinese vacuum tube produced by the Chinese firm Tsinghua Solar Co. type AMK SLU-1200/12 was used

The Chinese vacuum tube consists of two panels, each with 12 vacuum tubes. The tubes are constructed of two 3.3 mm concentric glass tube (borosilicate) with vacuum in between. The inner tube bears a coating of aluminiumnitrid which act as selective absorber. Along the inside of the inner glass tube solar collector liquid circulates in a U-tube of brass. To create a good heat transfer between the absorber and the collector fluid an aluminum cap is placed along the side the inside of the glass. By comparing the heat production of three plants, each with an area of 4.4 m², in the period 15-04-98 to 27-04-98, where the two of the plants (Plant 2 and Plant 3) was the traditional flat plate collectors a significantly larger heat production of the vacuum tube panel was achieved.

Vacuum tube panel 28.3 [kWh/24h x m²]

Plant 2 20.1 [kWh/24h x m²]

Plant 3 20.4 [kWh/24h x m²] By comparing the values of the measured period for the three plants it was demonstrated an increase in yield of approx. 40% for vacuum tube panel plant compared to conventional flat collectors.

At this background, it would therefore be expected to achieve an increased efficiency of air solar panels using vacuum tubes compared to traditional flat air heating panels at approx 40%.

The technical problem to be solved A major problem with known solar panels is the efficiency with which energy from sunlight can be converted into other energy forms, such as heat. This problem is particularly acute when the sun has an illumination angle of 45 degrees or less relative to a solar panel. When the sun has an approach at 30 degrees or less relative to a solar panel, the traditional air solar panels only produce a very limited or no heat at all.

The purpose of the invention is therefore to provide a solar air collector with an increased efficiency for heating an air stream used to heat buildings, especially focusing on the possibility of obtaining an increased heat production of solar panels when the sun has an approach at 45 degrees or below in compared to the solar panel. Here under it will be a purpose to provide a solar panel with an increased efficiency for heating the air used to heat buildings when the sun has an illumination angle of 30 degrees.

The new technique

The novelty of the air solar panel consists of a vacuum tubes, where said vacuum tubes on all sides is enclosed by a panel and where said vacuum tubes all are closed at one end, and each vacuum tubes encloses at least one inlet pipe. Therefore, the air from the inlet pipes can pass freely from the inlet pipes continuing past the inside of the vacuum tubes to the outside of vacuum tubes, this corresponds to the space outside the vacuum tubes that are bounded by the panel inside. The air solar panel also includes a fan that can be driven by an electric panel.

The heat absorbing element(s) in the air solar panel could be constituted by the inlet pipe and / or the vacuum tubes, the inlet pipe can be coated on the outside and the vacuum tubes can be coated on the inside, the outside or the inside and the outside.

On the inside of the air solar panel, including the back and edges of the air solar panel there can be installed one or more reflectors, which can reflect the sun's energy to the heat absorbing element(s).

The technical effect

By means of the new technique you achieve a significantly improved efficiency of air solar panel by heating the air passing through the panel, especially when the sun has an approach at 45 degrees to the solar panel.

By means of the new technique you achieve a dramatically improved efficiency of air solar panel by heating the air passing through the panel when the sun has an approach at 30 degrees to the solar panel. When the solar air collector is in operation preferable an electrical panel driven fan led an airflow through the solar panel from the air inlet to the air outlet, whereby the heated air will pass through three passages inside the solar air collector: first through the heated inlet pipe, then between the heated inlet pipe and the inside of vacuum tubes before the air finally being led along the outside of the vacuum tubes and the inside of the solar panel before the strongly heated air is blown into the building.

When needed, it is possible to reverse the flow direction of the solar air collector, by reversing the direction of the fan, thereby partly to reduce the risk of overheating of the solar air collector and partly in order to use the solar air collector for cooling of buildings.

The new technical effect can be provided by an air solar panel: where the front panel is covered by a transparent plate

where the back of the panel has mounted at least one reflector plate, where the^' cold outside air passes through the inlet pipe,

where the inlet pipes are enclosed in vacuum

where vacuum tubes are closed at one end and

where the air comes out of the mouth of the inlet pipes run along the inside of vacuum tubes and further along the outside of the vacuum tubes before the heated air is led into a room by the means of a ventilator. In the present invention a highly efficient heating of airflows can be achieved.

Because the front panel is covered by a transparent plate to accommodate a minimum reflection of the sunlight and an optimum heating of the heat-absorbing elements, implicitly the airstream passing the air solar panel.

Because on the back of the panel there is mounted at least one reflector plate to provide a reflection of the heat radiation into the air inside the air solar panel. Because the cold air from the outside passes through the inlet pipe, if convenient after the air has been filtered for dust etc, whereby the cold air from the outside pass through the inlet pipe is heated. Because the inlet pipes are enclosed in vacuum tubes you obtain partly a

substantially better utilization of heat radiation from the sun, partly an insulating shielding from the heat radiation from the heated air enclosed by vacuum tubes and partly an extended shelf life of the heat-absorbing material which may be affixed inside of the vacuum tubes.

Because vacuum tubes are closed at one end is you obtain that the air flow can pass from the inlet pipes and down along the outside of the inlet pipe / inside of vacuum tubes, where the airflow is heated further up from where the airflow be passed along the outside of the vacuum tubes / inner side of air solar panel, where the airflow becomes warmed up even more before the heated air is led into a room through an outlet by means of a fan.

By an appropriate embodiment of the invention, as indicated in claim 2, the transparent plate can be made of glass or a plastic, including e.g. polycarbonate to consider a very limited reflection of heat radiation from the sunlight to facilitate the heating of the air flowing through the air solar panel.

Polycarbonate is only mentioned as an example and should not be considered as a limitation of the scope of the invention.

As stated in claim 3, reflector plate or reflector plates may be constructed of aluminum to consider an effective reflection of the heat radiation from sunlight: partly to the heat absorbing element(s) in the air solar panel and partly to the air flowing through air solar panel and partly to the air flowing through air solar panel. It is considered to be within the scope for a skilled person in the field to suggest a reflective material with an equivalent or even a better reflectivity. In an embodiment of the invention as indicated in claim 4 the inlet pipe is made of aluminum, this material provides a high thermal conductivity, which is essential to bring the incoming air in the inlet pipe a preheating before this air is carried forward into the air solar panel. It is considered to be within the scope for a skilled person in the field to suggest another material with a similar or even a better thermal conductivity.

In an embodiment of the invention as stated in claim 5 the fan may be a solar driven fan hereby you obtain partly that there will be no need for an external power source and partly that there will be produced electricity exactly when needed to the fan from a renewable energy source.

In the preferred embodiment of the invention as stated in claim 6 a heat absorbing material has been applied to the inlet tubes and / or the vacuum tubes. By applying a heat absorbing material on an area inside an air solar panel this particular area will be heated by the sun's heat radiation. When the air then passes such an area the air becomes heated by the reflecting heat radiation from the heat absorbing material.

The vacuum tubes may be covered with a heat absorbing material with a dark color on the inside, outside or inside and outside.

When using an embodiment of the invention where heat absorbing material has been applied to the outside of vacuum tubes it may be an advantage to obtain a partial passage of the sunlight whereby you achieve a partial heating of the inlet pipes to obtain a heating of the air when it passes into the cavity defined by outer side of the inlet pipe and the inside of vacuum tubes. A partial passage of sunlight through the outside of the vacuum tubes can be achieved by applying the vacuum tubes with a transparent material or by a partial application of the heat absorbing material in confined areas the latter effect can be achieved by using a spray nozzle.

In the preferred embodiment of invention as stated in claim 6 a heat absorbing material has been used said material may be applied inside of the vacuum tubes. Even when a non-transparent heat absorbing material has been applied you can obtained the advantage that the heat absorbing material deliver the heat

accumulated both toward the inlet pipe and out towards the inside of air solar panel. The heat radiation from the heat absorbing material inside the vacuum tubes can through the cavity defined by the outer side of the inlet pipe and the inside of vacuum tubes transfer heat to the inlet pipes. When the inlet pipes are heated the heat can propagate further to the air drawn into the inlet pipes and thereby satisfy the initial heating of the air. In the preferred embodiment of the invention as stated in claim 6 a heat absorbing material has been used said material may be affixed to the inlet pipe hereby you can obtained the advantage that the warming is increased both by the airflow passing into the inlet pipes and by the airflow passing between the outside of the inlet pipes and the inside of vacuum tubes.

In the preferred embodiment of invention as stated in claim 7 the air solar panel contains a threefold consecutive cavity: the volume inside the inlet pipes, the volume between the inlet pipe and the inside of vacuum tubes and the volume between the outside of vacuum tubes and inside of air solar panel. Hereby you obtain a thermal gradient all through the panel starting from the air intake where the cold fresh air from the outside is routed through the inlet pipe where it achieves an incipient heating, the air flows continue from the inlet pipes where it is carried forward past the mouth of the inlet pipes and down along the outside of the inlet pipe / inner surface of vacuum tubes where the airflow is heated up further and eventually the air is led along the outside of the vacuum tubes / inner side of the panel where the air is heated further before the strongly heated air is let into a room through an outlet by means of a fan.

The heat absorbing material may e.g. be a coating of aluminiumnitrid.

Aluminiumnitrid is only mentioned as an example and should not be seen as limitation of the scope of the invention. Embodiment of the invention

When the solar air collector starts to operate cold air is sucked into the inlet pipe at the bottom of air solar panel. The air leaves the top of the inlet pipe where it pushes the hot air which is in the pipes along the outside of the inlet pipe / inside of vacuum tubes further into the panel, which subsequently is blown into the house of a solar driven fan.

The front of the panel is covered with glass, the back of the panel with an aluminum plate. When the sun shines an electric panel at the top of the solar air collector

(located in front of the hole for the fan) provides the fan with 12 volt and the fan blows air from the panel into the house.

When the solar air collector is in a continuous operation the inside of the vacuum tubes are heated together with the airflow around them in a specific embodiment of the invention.

Vacuum tubes are constructed like a vacuum flask with a clear outer surface where sunlight can pass, and a special surface on the inside, which absorbs sunlight and converts it to heat. While the inside of the vacuum tubes is heated, this heat will be transferred to the aluminum tubes installed inside glass tubes.

When the fan blows air into the house it leads to a negative pressure in the panel therefore cold air is pulled from the outside up through the aluminum pipes which then will pull cold air from outside through aluminum pipes and down through the cavity between the aluminum tubes and the vacuum tubes and out into the inside of the panel from which the heated air is blown into in the house.

The rear panel, preferably made of aluminum, has a great ability to reflect heat radiation from the incoming sunlight back into glass tubes. Because the air at a high temperature may contain significantly more water

(moisture) than air at a lower temperature the solar air collector can fulfill two functions; because the heated air flow from the solar air collector can both provide for the removal of moisture from houses and other enclosed spaces while houses and other enclosed spaces is being heated.

It will be affordable for manufacturers of solar air collectors to produce the solar air collector according to the invention, since the panels are essentially built in the same way as the known solar air collectors however with the essential difference that the solar air collector according to the invention applies vacuum tubes instead of the aluminum absorber which has hitherto been used.

In a preferred embodiment of the invention the direction of air flow through the solar air collector may be reversed. This makes the inlet to the outlet and correspondingly the outlet to the intake for air. If one or more fans lead the air flow through the solar air collector the direction of the air flow can be reversed by reversing the rotation of the fan(s).

The air sucked into the solar air collector is not necessarily pure, e.g. it can be contaminated with dust particles, pollen, soot and / or an unpleasant smell.

Filtering agents, such as a dust filter and / or a carbon filter can be used and preferably be located in, near and / or beside the air intake and / or air outlet.

Filtration of the air will extend the lifetime and increase the solar air collector efficiency because dust, dirt, grime and the like will be caught by the filter before the air enters the solar air collector. If the solar air collector according to the invention are provided as a heat source in a building or a room a filtering of the heated air generated by the solar air collector is preferable. In an embodiment of the invention the filter means can be replaced. Over time the performance of a filter will be reduced because of dust deposited in the filter and the back pressure will increase. When the filter is replaced, the performance will be restored and a clean air can be provided again to and from the solar air collector. A preferred embodiment of the invention the invention includes means to control the ventilation e.g. by controlling the speed of a ventilating fan, hereby the flow through the solar air collector can be controlled automatically. In a further embodiment of the invention which includes means to control the temperature in the compartment associated with solar air collector output. Said room temperature can for example be controlled by varying the quantity of heated air from the solar air collector, e.g. by varying a ventilation fan speed.

By means to control, turn and / or filter the air flow through the solar air collector you can achieve an additional objective of the invention. In an embodiment of the solar air collector according to the invention can thus provide both heating and ventilation of a room, a building, a car, a boat or a camper. Heating of a room, a building, a car, a boat or a camper associated with air outlet provided by drawing air from the outside, heating the air by letting it pass through a triple thermal gradient and blow the strongly heated air into a building, car, boat or camper. This mode of solar air collector can be called "heat mode" or "winter mode" since heating typically needed during a winter period. Ventilation and / or cooling the same room or building can be obtained by pulling air out and / or replace the air from that room a building, a car, a boat or a camper by reversing the airflow in the solar air collector, whereby the air outlet connected to the room or building acts as an air inlet and air intake in the solar air collector serves as outlet. This mode of solar air collector according to the invention can be termed "ventilation mode", "cool mode" or "summer mode" because during a warm period, typically the summer is cool and / or ventilation of the room or building more necessary than warming. Switching between summer and winter mode can be done automatically by the solar air collector, according to the invention. In another embodiment happens this conversion is made manually.

On a hot and sunny day, the heat absorbing element(s) inside the solar air collector can achieve a very high temperature, leading to a high temperature inside the solar air collector. This can cause damage to the solar air collector; therefore the solar air collector can include means for measuring and / or manage the internal temperature of the solar air collector for subsequent reversing fan direction when required. The solar air collector according to the invention can be applied for heating and / or ventilation of an entire building or one or more room inside a building.

The solar air collector can be installed on the wall and / or on a roof and / or be built into the same. The solar air collector external design can be varied, for example by using different materials for front and rear, to get it fit into various building

constructions. In an embodiment of the invention a front panel of tempered glass or glass-panel is affixed to the solar air collector on the outside to give the solar air collector, an external appearance like glass as a window.

The solar air collector according to the invention is not limited to heat and / or ventilate buildings. The solar air collector according to the invention can also provided heating and / or ventilation of cars, trucks, campers, caravans, boats and / or the like

The solar air collector, according to the invention can with advantage be used for summer cottage, for example installed on the roof. During the winter summer cottages are often heating a little e.g. to avoid freezing water pipes and / or cistern. An air collector according to the invention can help to heat and / or ventilate the cottage thereby heating costs can be reduced. There may also create a better overall indoor climate generated by solar air collector i.e. the solar air collector can be provided less moisture and / or a constant renewal of the indoor air. Thus the enclosed and often not ventilated odor in a cottage after a period out of use be avoided.

The air solar panel and embodiments of this according to the invention shall hereinafter be described with reference to the drawings.

Figure list

Fig. 1 shows a sectional view of an air solar panel

Fig. 2 shows a front view of an air solar panel Reference numbers in the figures:

Air solar panel

Inlet tube /pipe

Vacuum tube 12

Heat absorbing element 13

Front panel 14

Rear panel 15

Reflector plate 16

Air outlet 17

Ventilation unit 18

Intake of fresh air A

El-panel / solar cell B

Airflow (arrows)

Description of the drawing

The invention will below be described in more detail under reference to the drawing in which:

Fig. 1 shows a cross section of an embodiment of an air solar collector according to the invention, viewed from the side.

Fig. 2 shows an air solar collector according to the invention, a front view in perspective.

Detailed description of the invention

Fig. 1 shows a cross section of an embodiment of an air solar panel (10) according to the invention, viewed from the side where the vacuum tubes (12) is positioned in the space between the front panel (14) and rear air solar panel (10), in which air solar panel (10) affixed to a reflector plate (16), which reflects the heat radiation into the air inside the air solar panel

The front panel (14) is preferably made of glass or a plastic material such as polycarbonate.

The rear panel (15) is provided with an insulating layer (not shown in this

embodiment) to minimize heat loss through the rear panel (15). The airflow path inside the air solar panel (10) is indicated by arrows. The air can enter the solar air collector (10) through an inlet (A) comprising a plurality of holes in the bottom of the solar air collector (10) (not shown in this embodiment). The air passes a filter (not shown in this embodiment) to filter out dust, dirt and debris from the incoming air.

From the air intake placed air into a number of inlet pipe (1 1 ). After an initial warming of air inside the inlet pipe (1 1 ) placed on the air far from the inlet pipes (1 1 ) to the closed end of vacuum tubes (12). From the air intake the air is routed through a number of inlet pipes (1 1 ). After an initial warming of the air inside the inlet pipe (1 1 ) placed on the air is guided from the inlet pipes (1 1 ) to the closed end of the vacuum tubes (12).

From the closed end of the vacuum tubes (12) the partially heated air is guided further into the cavity between the exterior of inlet pipes (1 1 ) and the inside of vacuum tubes (12), where the air is heated further.

The air leaving the vacuum tubes (12) near the bottom of the air solar panel (10), after which the air is heated further in the cavity between vacuum tubes (12) and the inside of air solar panel (10). .

The airstream is leaving the air solar panel (10) through an outlet (17). The fig. 1 shows an embodiment where the airflow is guided through the air solar panel (10) by means of a ventilation unit (18) where the ventilation unit (18) is mounted in the air outlet (17). The strength of the air flow is regulated by a ventilation unit (18). The ventilation unit (18) is powered by the electrical energy generated by the solar panel (B).

The heat absorbing element(s) (13), in the air solar panel (10) may consist of inlet pipes (1 1 ) and / or vacuum tubes (12) affixed to a heat absorbing material. The inlet pipes (1 1 ) can be shiny metal tubes e.g. made of aluminum, to increase the heating of both the air that passes inside the inlet pipe (1 1 ) and the air which passes on the outside of inlet pipes (1 1 ) the inlet pipes (1 1 ), may be covered with a dark colored material to increase the absorption of heat energy from sunlight. The vacuum tubes (12) may be covered with a dark colored material on the inside, outside or inside and outside.

If the outside of the vacuum tubes (12) is applied to a heat absorbing material, one will preferably choose to achieve a partial passage of the sunlight hereby you will achieve a partial heating of the inlet pipes (1 1 ), thereby accommodate the heating of the air when it passes the cavity bounded by the outside of inlet pipes (1 1 ) and the inside of vacuum tubes (12). A partial passage of sunlight through the outside of the vacuum tubes (12) can be achieved by applying the vacuum tubes (12) a transparent material or by a partial application of heat absorbing material in confined areas the latter effect can be achieved by using a spray nozzle.

If the inside of the vacuum tubes (12) have applied a non-transparent heat absorbing material you may achieved that the heat absorbing material deliver the heat accumulated both toward the inlet pipes (1 1 ) and towards the inside of the air solar panel (10). The heat radiation from the heat absorbing material at the inside of the vacuum tubes (12) can through the cavity defined by outer side of the inlet pipes (1 1 ) and the inside of vacuum tubes (12) transfer heat to the inlet pipes (1 1 ). When the inlet pipes (1 1 ) get hot the heat can propagate further to the air drawn into the inlet pipes (1 1 ) and thereby satisfy the initial heating of the air.

Test results

To demonstrate the improved effectiveness of the air solar panel according to the invention compared to conventional air solar panels the air solar panel according to the invention was compared to an air solar panel with aluminum convectors of the labeled SV 07 Plus from Ans Solar Heating, DK-5800 Nyborg, Denmark.

The very SV 07 Plus from Ans Solar was chosen because this air solar panel is one of the commercially available air solar panels on the market with the highest performance. In the experiment the air solar panel according to the invention is named, SV 07 Vacuum P.

In order that the results could be as comparable as possible air solar panels with the same dimensions was used. The outside dimensions was 62 cm x 124 cm = 0.77 m². The survey was conducted by natural sunlight, October 9th 2009 from

10.00 to kl.12.00 pm.

The air intake had an average temperature of 6.5 °C. The relative humidity was 80%, equivalent to 6 grams of water vapor per m³.

- The heat capacity of air containing 6 grams of water per. m³ equals: 0.339 Wh per m³ per °C at 20 °C.

To heat 1 m³ of this air 10 degrees Celsius from 15 °C to 25 °C requires 10 x 0.339 Wh = 3.39 Wh. When the temperature of the intake air is 6.5 °C and the temperature of the air that enters the house rises from 6.5 °C to 14.5 °C the temperature has risen by 8.0 °C total, but the air is on average has only been heated to the half, equal to 4.0 °C. The air solar panels were placed at an angle of 30, 45, 60, 75 and 90 degrees to the sun, in order to simulate the sun's approach during the day.

Each position at 30, 45.60 and 75 degrees to the sun, was retained for one hour. The angle of 90 degrees (perpendicular) to the sun was retained for 30 minutes.

By an approach angle at 30 degrees to the sun the SV 07 Plus produced 1 .75 m³ of air that had achieved a temperature rise of 1 degree Celsius. This approximately corresponds to a power output of 0.339 Wh / m³ · °C x 0.5 x 1 °C x 1.75 m³ = 0.297 Wh.

By an approach angle at 30 degrees to the sun, for the SV 07 Vacuum P produced 15.75 m³ of air that had achieved a temperature rise of 8 degrees Celsius. This approximately corresponds to a power output of 0.339 Wh/ m³ '°C x 0.5 x 8 °C 15.75 m³ = 21.357 Wh.

By an approach angle at 30 degrees to the sun the SV 07 Vacuum P produced 72 times more energy than conventional air solar panel with aluminum convectors.

(Equivalent to 7200 percent). By an approach angle at 45 degrees to the sun the SV 07 Plus produced

3.50 m³ of air that had achieved a temperature rise of 4 degrees Celsius. This approximately corresponds to a power output: 0.339 Wh/ m^{3 »}°C x 0.5 x 4 °C x 3.50 m³ = 2.373 Wh. By an approach angle of 45 degrees to the sun the SV 07 Vacuum P produced 23.63 m³ of air that had achieved an increase in temperature of 1 1 degrees Celsius. This approximately corresponds to a power output: 0.339 Wh/ m³ · °C x 0.5 x 1 1 °C x 23.63 m³ = 44.058 Wh.

By an approach angle at 45 degrees to the sun the SV 07 Vacuum P produced 18.6 times more energy than conventional air solar panel with aluminum convectors.

By an approach angle at 60 degrees to the sun the SV 07 Plus produced 12.25 m3 of air that had achieved an increase in temperature of 9 degrees Celsius. This corresponds approximate to a power output: 0.339 Wh/ m³ · °C x 0.5 x 9 x OC 12.25 m³ = 18.687 Wh.

By an approach angle at 60 degrees to the sun the SV 07 Vacuum P produced 27.13 m3 of air that had achieved an increase in temperature of 7 degrees Celsius. This approximately corresponds to a power output: 0.339 Wh/ m³ · °C x 0.5 x 17 x OC 27.13 m³ = 78.175 Wh.

By an approach angle at 60 degrees to the sun the SV 07 Vacuum P produced 4.2 times more energy than conventional air solar panel with aluminum convectors.

By an approach angle at 75 degrees to the sun the SV 07 Plus produced 18.38 m3 of air that had achieved an increase in temperature of 13 degrees Celsius. This corresponds approximate to a power output: 0.339 Wh/ m³ · °C x 0.5 x 13 °C x 18.38 m³ = 40.500 Wh.

By an approach angle at 75 degrees to the sun the SV 07 Vacuum P produced 38.50 m3 of air that had achieved an increase in temperature of 20 degrees Celsius. This approximately corresponds to a power output: 0.339 Wh/ m³ · °C x 0.5 x 20 ° x 38.50 m³ = 130.515 Wh.

By an approach angle at 75 degrees to the sun the SV 07 Vacuum P produced 3.2 times more energy than conventional air solar panel with aluminum convectors. By an approach angle at 90 degrees to the sun, for the SV 07 Plus produced 21 .00 m³ of air that had achieved an increase in temperature of 20 degree Celsius. This approximately corresponds to a power output: 0.5 x 0.339 Wh/ m³ · °C x 0.5 x 20 °C x 21 .00 m³ = 35.595 Wh.

By an approach angle at 90 degrees to the sun, for the SV 07 Vacuum P produced 43.75 m³ of air that had achieved an increase in temperature of 25 degrees Celsius. This approximately corresponds to a power output: 0.5 x 0.339 Wh / m³ · °C x 0.5 x 25 °C x 43.75 m³ = 92.696 Wh.

By an approach angle at 90 degrees to the sun SV 07 Vacuum P produced 2.6 times more energy than conventional air solar panel with aluminum convectors.

This means that the air solar panel according to the invention by an approach angle at respectively 30, 45, 60, 75 and 90 degrees produced sun produced 72.0 ; 18.6 ; 4.2 ; 3.2 and 2.6 times more energy than conventional air solar panel with aluminum convectors.

Discussion of the test results The dramatic increase in efficiency of the air solar panel according to the invention can be due to the fact that the airflow is heated in three separate areas. The first heating of air takes place inside the inlet pipe, the next heating of air takes place in the cavity between the inlet pipe and the inside of vacuum tubes and the last heating of the air in the cavity between the vacuum tubes and the inside of the panel before the air is led out of the heating panel. When the air is heated it takes place through three cavities, which together describe a strong thermal gradient.

By a comparison with the present invention and the closest known technique for air solar panels containing vacuum tubes it can be seen that the airflow in the known air solar panels containing vacuum tubes it is only exposed to a warming in two separate areas.

Claims

1. Air solar panel characterized by

that the front of the panel is covered by a transparent plate, that on the back of the panel is mounted at least one reflector plate, that the cold outside air passes through the inlet pipe, that the inlet pipes are enclosed in vacuum tubes, that vacuum tubes are closed at one end and that the air coming out of the mouth of the inlet pipes run along the inside of vacuum tubes and along the outside of the vacuum tubes before the heated air is led into a room through a ventilator.

2. Air solar panel according to claim 1 characterized by

that the transparent plate is made of glass or plastic.

3. Air solar panel according to claim 1 characterized by

that the reflector plate is made of aluminum

4. Air solar panel according to claim 1 characterized by

that the inlet pipe is made of aluminum

5. Air solar panel according to claim 1 characterized by

that the fan is a solar driven fan.

6. Air solar panel according to claim 1 characterized by

that the heat absorbing element(s) in the air solar panel consists of inlet pipes and / or vacuum tubes applied a heat absorbing material.

7. Air solar panel according to claim 1 characterized by

that the air solar panel contains three consecutive cavities: a cavity inside the inlet pipes, a cavity between the inlet pipe and the inside of vacuum tubes and a cavity between the outside of vacuum tubes and inside of air solar panel.