IMPROVED SOLAR PANEL HEAT DISSIPATION SYSTEM
Field of Invention
The present invention relates to an improved solar panel heat dissipation system and more particularly to a solar panel with heat reflective specific coating to prevent excessive heating of the panel thereby increasing its efficiency.
Background of the Invention
Solar panels are typically made of solar cells arranged in multiple layer planar axis .Electric current is produced when photons from solar ray falls on the photo-reactive solar cells, electrons jump the energy state at the junctions .
In many of the solar panel system, normally metallic structure is used to impart mechanical strength to the whole system. These structures some time may act as the heat sink for high concentration system also. The normal way of increasing the efficiency of the solar cell is to cause more photons fall on the cells by using light concentrators . However increasing the concentration of incident photons also leads to increased heating of the panel. Therefore a heat sink is used to dissipate the heat in view of the fact that the elevation in the temperature of the system can lead to decrease in the panel efficiency.
The theoretical values of solar cell efficiency is not possible to achieve in the practical environment. The reason behind this is that the lab condition is much controlled and the cell efficiency Is being measured at the room temperature of 28 °C. In Practical condition the temperature of the solar cell becomes quite higher than the lab condition.
As discussed above , metal plates of different kinds have been used as heat sink to dissipate the heat generated in the solar panels . Efforts has also been made to reduce the cell temperature using different cooling fin design. Different cooling agents like water, ammonia etc have also been used. The solution provided earlier is , however, costly and also not efficient.
In PCT patent publication W02007/089333 multilayer coating (notch filter) has been used on the top of the multi junction solar cell to reflect the light of a particular wavelength which is not required by the solar cell as it would only produce heat.

However, there is a constant need of a solution which can provide better efficiency of the solar cell module by preventing rise in temperature without compromising the power generation output of the solar panel.
Objects of the Invention
It is the primary object of the present invention to provide improved solar panel.
It is another object of the invention to reduce the temperature of the metal back panel of the
solar panel , thereby increasing the overall efficiency.
It is yet another object of the present invention to use reflective layers in the solar panels to
reflect unwanted solar rays from the solar panel, thereby reducing thermal heating.
It is a further object of the invention to provide for a cost efficient soiar panel.
Summary of the Invention
Accordingly the present invention provides an improved solar panel with metallic panel used as a
heat sink comprising reflective means disposed on the front glass panel of the said solar panel
adapted to prevent unutilised solar rays from reaching the said metallic heat sink located at the
back of the panel, thereby increasing the overall efficiency .
The said the reflective means is provided in the gaps of the packing area of the solar ceil array.
Preferably the said reflective means is made of aluminium foil or white reflective paint.
The aluminium foil is attached with the glass panel by known means such as gluing.
The invention also provides a method of manufacturing of an improved solar panel with metallic
panel used as heat sink comprising providing a solar panel and providing reflective means of
aluminium foil or white reflective paint on the front glass panel in the gaps of the packing area of
the solar cell array.
Brief Description of the Accompanying Drawings
Fig 1 is a comparative illustration of a normal solar cell array of a solar panel vis-s vis a solar cell array with reflective coatings applied in the vacant space.
The present Invention is described in detail hereinafter with the help of exemplary embodiments.

Detailed Description of the Invention
The photons from the solar rays produces electron according to its quantum efficiency. The electrons jumps their energy states at the junctions of the solar cells to produce photo current. It is theoretically possible to arrive at a conclusion as to the expected current generation of solar panels based on the structure of the panel, materials used for making the solar cells and the on the spectrum analysis of the incident rays. However, as discussed earlier , heating of the back metallic panel , which acts as heat sink decrease the overall efficiency of the solar panel.
The present invention provides a cheap and easily implement-able option to this problem. Increasing the effectiveness of the heat sink can reduce the temperature of the solar panel and thereby increasing the overall efficiency of the panel.
Normally the Solar panel do not have packing density more than 80 % i.e. the 20% or more area of the solar panel is not being used for photovoltaic application. This is shown in the accompanying figure 1 and marked as unblocked panel,
In this unused area the sunlight falls directly on the metal heat sink structure which is located at the back of the solar cell panel . The metal absorbs this energy and so the temperature of the structure get increases which in turn leads to ineffective cooling of photovoltaic material. Ineffective cooling of the solar panel reduces the over all efficiency and the current generation.
Therefore , if falling of sunlight directly to the back panel can be reduced or blocked , temperature of back panel can be reduced , heat transfer from solar cell to outside environment through back panel will become efficient and hence solar cell temperature will be reduced and efficiency of solar cell will be increased.
On the basis of this concept a reflective coating technology on the front glass has been developed .. This will reduce the incident solar energy directly falling on the metal structure .The reflective coating concept on the front glass can be implemented easily in order to avoid excess heating of panel from unused area.
In the present invention a cover on the front glass of the total solar panel is provided . This front cover is specifically placed in the gaps of the packing of the solar cells in the panel. This cover can be made using an Aluminium foil or a white stable paint on the front glass surface in specific

areas. This is shown in figure 1 and marked as blocked panel. It can be readily seen that the gaps of the solar cell packing has been covered by aluminium foils so as to prevent unutilized Sun rays passing through this gaps and falling directly on the back panel metal structure Theoretical calculation using approximations has been done. Thermal strips for practical verification have been used . It is known that temperature effect on cell efficiency (for tripple junction solar cells, 1% efficiency increase with decrease in temperature of cell by 10 degree celcius). So using thermal strips on different positions of module, temperature variation due to cover made of aluminium foil and white paint, on front glass and without cover have been checked and is found to be satisfactory..
It is aimed to reduce the temperature of the solar material by reducing the temperature of metallic solar panel structure. The invented solution reduces the temperature of the metal and so it increases the cooling effect of the Photovoltaic material. The increase cooling efficiency leads to higher cell / panel efficiency.
The instant invention has been described with the help of exemplary embodiments only . Various modifications and alterations can be thought of without departing from of the spirit and scope of the invention as defined in the appended claims.

We claim,
1. An improved solar panel with metallic panel used as a heat sink comprising reflective means disposed on the front glass panel of the said solar panel adapted to prevent unutilised solar rays from reaching the said metallic heat sink located at the back of the panel, thereby increasing the overall efficiency .
2. An improved solar panel as claimed in claim 1, wherein the reflective means is provided in the
gaps of the packing area of the solar cell array,
3. An Improved solar panel as claimed in claim 1 or 2 ,wherein the said reflective means is made
of aluminium foil or white reflective paint.
4. An improved solar panel as claimed in claim 3 , wherein the aluminium foil is attached with the
glass panel by known means such as gluing,
5. A method of manufacturing of an improved solar panel with metallic panel used as heat sink comprising providing a solar panel and providing reflective means of aluminium foil or white reflective paint on the front glass panel in the gaps of the packing area of the solar cell array.
6. A method of manufacturing of an improved solar panel with metallic panel used as heat sink as claimed in claim 5 , wherein said alunminium foil is attached with the glass panel by known means such as gluing.
Dated this 25th day of February 2008