Description:A device for monitoring performance of solar panel and method thereof
Field of the Invention
The present invention relates to device for evaluating working performance of solar panels. More particularly, the present invention relates to device for measuring and monitoring efficiency of solar panels.
Background of the Invention
Solar panels are a key component of renewable energy systems, converting sunlight into electricity through the photovoltaic effect. Over the years, solar panel technology has made significant advancements, becoming increasingly efficient in harnessing solar energy. However, even with these advancements, solar panels are still subject to certain limitations that can lower their overall efficiency.
One of the primary factors affecting solar panel efficiency is the conversion of sunlight into usable electrical energy. Solar panels rely on the absorption of photons from sunlight by semiconductor materials, typically made of silicon. Not all photons can be absorbed, and those that are absorbed may not always result in the generation of electricity. Some photons may be reflected or pass through the panel without interacting with the semiconductor material, leading to energy loss.
Additionally, various environmental and external factors can impact the efficiency of solar panels. Dust, dirt, pollen, and other particles that accumulate on the surface of the panels can reduce the amount of sunlight reaching the semiconductor material, thereby decreasing efficiency. Similarly, shading caused by nearby objects such as buildings, trees, or debris can significantly impact the performance of solar panels by reducing the amount of sunlight they receive.
Temperature also plays a crucial role in solar panel efficiency. Solar panels absorb a part of the solar radiation falling on it to convert it in electricity. Rest of the radiations, which is falling on solar panels and are not converted in electricity are converted in heat. Higher temperatures can negatively affect the performance of the semiconductor materials, causing a decrease in electrical output. This phenomenon, known as the temperature coefficient, varies depending on the specific materials used in the solar panels.
Furthermore, the angle and orientation of solar panels relative to the sun's position throughout the day can affect their efficiency. Optimal alignment ensures that the panels receive the maximum amount of sunlight, optimizing energy generation. However, as the sun moves across the sky, maintaining the ideal orientation becomes a challenge.
Degradation over time is another factor contributing to lowered efficiency. Exposure to sunlight, heat, and environmental factors can cause wear and tear on solar panels, leading to a gradual decrease in their performance over the years. This degradation is typically accounted for by manufacturers and is considered in the panel's rated power output and expected lifespan.
If a solar panel of a string / group is not as efficient as other panels, it not only gives a lesser generation of its own, but it also prevents other panels from generating power efficiently. Then, the efficiency of the plant is drastically reduced, resulting in a big financial loss.
Therefore, detection of deficient sections and measurement of efficiency of individual solar panels of all such sections of a plant is important. Further to which, if required, a replacement / interchange plan can be imposed with a techno-economic justification. With this one-time work, it is possible to achieve enhanced power generation from the plant for the same conditions of solar radiation and thereby, reduced financial losses.
In the current practice, the efficiency of panels, along with other parameters are measured based on the rating provided on the solar panel and electricity being produced due to the solar panel. However, this may not be an accurate measuring technique in absolute terms as solar irradiance may vary with time and day of the year, therefore the actual output efficiency might vary.
There are various other solutions that have been provided according to the existing arts, but all these solutions still have challenges because of their limited applications and inefficient functioning. It is, therefore, important and desirable to work on the alternative solution to develop a device for measuring efficiency of solar panels based on real time solar irradiance available for incidence at any point of time and obviates challenges, complexity and drawbacks associated with the prior arts.
Summary of the Invention
This summary is provided to introduce a selection of concepts in a simplified form that are further described below in the Detailed Description. This summary is not intended to identify key features or essential features of the claimed subject matter. Nor is this summary intended to be used to limit the claimed subject matter’s scope.
Both the foregoing summary and the following detailed description provide examples and are explanatory only. Accordingly, the foregoing summary and the following detailed description should not be considered to be restrictive. Further, features or variations may be provided in addition to those set forth herein. For example, embodiments may be directed to various feature combinations and sub-combinations described in the detailed description.
It is one of the objectives of the present invention to provide a performance monitoring device for solar panels which avoids external power source for supply required to auxiliaries of the device (cooling fan, Displays, etc) and instead uses generated power of solar panel as auxiliary supply at the time of testing and measurement.
It is one of the objectives of the present invention to provide a performance monitoring device for solar panels which consumes actual generated power of solar panel at the time of testing and measures generated power.
It is another objective of the present invention to provide a performance monitoring device for solar panels which is configured to measure output power efficiency based on radiation level of the sun rays (solar irradiance) falling on the solar panel.
Another objective of the present invention is to provide an efficiency measuring device for solar panels which is cost effective and automatically# displays the real time efficiency of the solar panel.
As a preliminary matter, it will readily be understood by one having ordinary skill in the relevant art that the present disclosure has broad utility and application. As should be understood, any embodiment may incorporate only one or a plurality of the above-disclosed aspects of the disclosure and may further incorporate only one or a plurality of the above-disclosed features. Furthermore, any embodiment discussed and identified as being “preferred” is considered to be part of a best mode contemplated for carrying out the embodiments of the present disclosure. Other embodiments also may be discussed for additional illustrative purposes in providing a full and enabling disclosure. Moreover, many embodiments, such as adaptations, variations, modifications, and equivalent arrangements, will be implicitly disclosed by the embodiments described herein and fall within the scope of the present disclosure.

Accordingly, while embodiments are described herein in detail in relation to one or more embodiments, it is to be understood that this disclosure is illustrative and exemplary of the present disclosure and are made merely for the purposes of providing a full and enabling disclosure. The detailed disclosure herein of one or more embodiments is not intended, nor is to be construed, to limit the scope of patent protection afforded in any claim of a patent issuing here from, which scope is to be defined by the claims and the equivalents thereof. It is not intended that the scope of patent protection be defined by reading into any claim a limitation found herein that does not explicitly appear in the claim itself.
Additionally, it is important to note that each term used herein refers to that which an ordinary artisan would understand such term to mean based on the contextual use of such term herein. To the extent that the meaning of a term used herein—as understood by the ordinary artisan based on the contextual use of such term—differs in any way from any particular dictionary definition of such term, it is intended that the meaning of the term as understood by the ordinary artisan should prevail.

Furthermore, it is important to note that, as used herein, “a” and “an” each generally denotes “at least one,” but does not exclude a plurality unless the contextual use dictates otherwise. When used herein to join a list of items, “or” , “/” denotes “at least one of the items,” but does not exclude a plurality of items of the list. Finally, when used herein to join a list of items, “and” denotes “all of the items of the list.”
In accordance with one embodiment of the present invention, there is provided a performance monitoring device for solar panel(s), comprises of a solar power input connection terminal, a metering module configured to measure and display value of one or more electrical parameters, an electronic control circuit connected to a load resistor for controlling the magnitude of voltage load at the load resistor element with the help of one or more potentiometers, DC-DC converter for functioning auxiliaries at its prescribed voltage, wherein said metering module displays maximum obtainable power from the solar panel by varying voltage to be applied at the load resistor element by way of the one or more potentiometers.
In accordance with one embodiment of the present invention, there is provided a performance monitoring device for solar panel(s), comprises of a solar power input connection terminal, a metering module configured to measure and display value of one or more electrical parameters, an electronic control circuit connected to a load resistor for controlling the magnitude of voltage load at the load resistor element with the help of one or more potentiometers, DC-DC converter for functioning auxiliaries at its prescribed voltage, wherein said metering module displays maximum obtainable power from the solar panel by varying voltage to be applied at the load resistor element by way of the one or more potentiometers, wherein said electrical parameters include but not limited to maximum power (Pmax), short circuit current (Is), maximum voltage (Vmaxp) and current (Imaxp) at maximum power, power output efficiency of the solar panel.
In accordance with one embodiment of the present invention, there is provided a performance monitoring device for solar panel(s), comprises of a solar power input connection terminal, a metering module configured to measure and display value of one or more electrical parameters, an electronic control circuit connected to a load resistor for controlling the magnitude of voltage load at the load resistor element with the help of one or more potentiometers, DC-DC converter for functioning auxiliaries at its prescribed voltage, wherein said metering module displays maximum obtainable power from the solar panel by varying voltage to be applied at the load resistor element by way of the one or more potentiometers, wherein said power output efficiency of the solar panel is calculated based on the irradiance available due to sun on the solar panel at the time of efficiency measurement.
In accordance with one embodiment of the present invention, there is provided a performance monitoring device for solar panel(s), comprises of a solar power input connection terminal, a metering module configured to measure and display value of one or more electrical parameters, an electronic control circuit connected to a load resistor for controlling the magnitude of voltage load at the load resistor element with the help of one or more potentiometers, DC-DC converter for functioning auxiliaries at its prescribed voltage, wherein said metering module displays maximum obtainable power from the solar panel by varying voltage to be applied at the load resistor element by way of the one or more potentiometers, wherein said device is designed to display temperature of the load resistor element on its front interface with the help of temperature sensors coupled to the load resistor element.
In accordance with one embodiment of the present invention, there is provided a performance monitoring device for solar panel(s), comprises of a solar power input connection terminal, a metering module configured to measure and display value of one or more electrical parameters, an electronic control circuit connected to a load resistor for controlling the magnitude of voltage load at the load resistor element with the help of one or more potentiometers, DC-DC converter for functioning auxiliaries at its prescribed voltage, wherein said metering module displays maximum obtainable power from the solar panel by varying voltage to be applied at the load resistor element by way of the one or more potentiometers, wherein said device comprises of a temperature controller for monitoring the temperature of the load resistive element of the device and configured to automatically switch off the device with the help of a relay in exceptional circumstances.
In accordance with one embodiment of the present invention, there is provided a performance monitoring device for solar panel(s), comprises of a solar power input connection terminal, a metering module configured to measure and display value of one or more electrical parameters, an electronic control circuit connected to a load resistor for controlling the magnitude of voltage load at the load resistor element with the help of one or more potentiometers, DC-DC converter for functioning auxiliaries at its prescribed voltage, wherein said metering module displays maximum obtainable power from the solar panel by varying voltage to be applied at the load resistor element by way of the one or more potentiometers, wherein said device comprises of one or more capacitors connected with the DC-DC converter for storing energy and supply it as auxiliary supply for measuring short circuit current in case when solar panel is unable to provide any power supply.
In accordance with another embodiment of the present invention, there is provided a method for monitoring performance of solar panel(s), comprises of receiving power from the solar panel at a solar power input connection terminal, controlling magnitude of voltage to be supplied to a load resistor element by varying voltage at one or more potentiometers, and obtaining maximum power obtainable from the solar panel for calculating the actual working efficiency of the solar panel based on the irradiance available due to sun on the solar panel at the time of efficiency measurement.
In accordance with another embodiment of the present invention, there is provided an efficiency measuring device for solar panel(s), comprises of a solar power input connection terminal, a metering module configured to measure and display value of one or more electrical parameters, load resistor element controlled by a control switch, and provided with one or more tapping means enabling power selection in a range, and connected to a DC-DC converter for functioning at its prescribed voltage, an electronic control circuit connected to the load resistor for controlling the magnitude of voltage load at the load resistor element with the help of one or more potentiometers, and one or more capacitors connected with the DC DC converter for storing energy received from the solar panels, wherein the device utilises the stored energy in the capacitor for the measurement of said one or more electrical parameters without requiring any external power source.
Brief Description of the accompanying drawing
Figure 1 illustrates the structural arrangement and internal connection of the components within the device for monitoring performance of the solar panel.
Figure 2 illustrates the circuit for measurement of open circuit voltage.
Figure 3 illustrates the circuit diagram for measurement of the maximum power and set of points on IV curve with solar panel efficiency meter (SPEM).
Figure 4 illustrates the circuit for measurement of short circuit current with solar panel efficiency meter (SPEM).
Detailed Description of the Invention

The following detailed description refers to the accompanying drawings. Wherever possible, the same reference numbers are used in the drawings and the following description to refer to the same or similar elements. While many embodiments of the disclosure may be described, modifications, adaptations, and other implementations are possible. For example, substitutions, additions, or modifications may be made to the elements illustrated in the drawings, and the methods described herein may be modified by substituting, reordering, or adding stages to the disclosed methods. Accordingly, the following detailed description does not limit the disclosure. Instead, the proper scope of the disclosure is defined by the appended claims. The present disclosure contains headers. It should be understood that these headers are used as references and are not to be construed as limiting upon the subjected matter disclosed under the header.
The principle on which the invented device for solar panel work is achieving maximum power condition and based on which the output efficiency is evaluated with respect to available solar power irradiance falling on the solar panels, wherein any source of power has its own I-V characteristics, i. e. , when it is subjected to different loading conditions, output voltage varies with current following a pattern. At such different loading conditions, output power of the source is also varying and there is a ‘maximum power’ condition.
In the present invention the solar panel under test is to be isolated from other panels / plant and is to be connected with the device, wherein the panel receives solar irradiance (in general terms radiation) at an angle and the power flow to the in-built load of the device is controlled and condition of maximum power is achieved, wherein this is the power generation capacity of the panel at that irradiance level.
In the present invention, DC supply of the solar panel is used as working supply for the device for reliability and convenience, wherein no battery or mains supply is used for the device for measurement of panels.
The device of the present invention can be used for measurement of panels having ‘open circuit voltage’ up to 85 V.
In the present invention, a parameter ‘Open circuit voltage’ of the panel is measured as if no power is drawn from the panel. Further, the device has an inbuilt resistive loading arrangement changeable in 3 steps and the input power to the load is controlled by an electronic control circuit.
Further, the resistive load is gradually increased manually or automatically#, and different points of I-V characteristics of the panel are obtained, wherein this setup is tuned to receive & measure maximum power, wherein said maximum power condition is achieved at a particular voltage and current decided by I-V characteristic of the panel, wherein the parameters ‘Maximum power’, ‘voltage at maximum power’ and ‘current at maximum power’ are noted and accordingly, efficiency of the solar panel is calculated based on the available solar irradiance falling on the solar panel, wherein a definite amount of energy of solar panel is stored in the device while measuring the above parameters using the capacitor.
Further, another parameter ‘Short circuit current’ is recorded by shorting the terminals of panels with a switch available on the device, and at the time of measurement of ‘Short circuit current’, as the power from solar panel is not available, the device operates using working power / auxiliary supply from the stored energy.
In the present invention, the disclosed device is provided with displays to show temperature of the device, an alarm (audio) and arrangement of cutoff form load when a set temperature is reached due to overheating, three selectable current ranges, a special circuit made of three Potentiometers (variable resistors) enable operator to have three sensitivity level of control.
Further, the device is configured to work automatically# for obtaining maximum power condition, and to obtain maximum power reading, the point at which the maxima is obtained is constantly monitored on the power display meter by turning three potentiometers knobs in a combination, this is manual mode of operation, whereas, in automatic mode, instead of turning the knobs, a push button is pressed once, electronic power control circuit enable different power flows from solar panel to load and after obtaining maximum power, automatically# it stops at maximum power condition.
In the present invention, the device is configured to measure (at certain irradiance level and at a temperature) Open circuit voltage, Maximum power, Voltage and current at maximum power, Short circuit current, Operational efficiency of the panel is evaluated with the help of above parameters and determines a set of points at I-V Characteristics.
In the present invention, the device can make measurements for panels having ‘open circuit voltage up to 85V. No main's supply, battery or auxiliary voltage source is needed for measurements of pane, having Voc up to 85 volts wherein the device uses power of Solar panel for its auxiliary supply requirement and this feature allows movement of the device in any part of the yard area, where there are no constraint of availability of mains supply or status of battery.
Further, while the measurements are being taken, an inbuilt capacitor stores energy for future and when measurement of short circuit current is being taken, as solar panel is not in position to supply any power, the device uses the stored energy for its auxiliary supply.
Further, the device is encapsulated in waterproof enclosure and also provided with fuses for over load protection, wherein the user closes the enclosure as soon as he finds rains, being at a distant location from the control room. Furthermore, the device displays temperature of the load resistive element and also of its own and if the temperature is increased beyond a set value, an alarm is created and load of the solar panel is automatically cut off, wherein the device is used after it is cooled to a set low temperature.
In accordance with one embodiment of the present invention, there is provided a device comprising a load resister that receives power from solar panel and dissipate it, wherein the power is controlled by an electronic control circuit and a command to the control circuit is given by varying control voltage obtained by three potentiometers. Further, an operator achieves maximum power condition by rotating the knobs of the potentiometers which is displayed as DC power, wherein a DC-DC converter is used to convert DC voltage of panel to 12 V DC and this voltage is used as auxiliary voltage, to be used for cooling fan and metering modules.
Further, in the present invention, DC supply of the solar panel is used as working supply for the device for reliability and convenience, and no battery or mains supply is required for the device for measurement of panels, wherein a capacitor is used for storing energy and energy of solar panel to some extent is stored in the capacitor, while measurements are being carried out (except measurement of short circuit current).
In the present invention, the device has two terminals for connectivity to solar panel and as the device is turned ON, open circuit voltage is measured in the device which is capable of measuring DC voltage, current and power (other functionality used subsequently), wherein another switch load control is turned ON, which couples solar panel to the load through an electronic load control circuit and through an over temperature trip relay, wherein the load is a resistor having 2 tappings to get 3 values of resistance, changeable with switches for power-range-selection.
Further, the electronic load control circuit is basically a transistor circuit, in which output current (and hence power) in collector circuit is switched ON and OFF periodically by applying a train of pulses at base current, wherein the duty cycle i.e. ratio of ON time to total period of a cycle is controlled by control knobs, which results in control on power.
In the device of the present invention, there are provided temperature sensors and temperature display modules to display the device temperature and if the temperature goes beyond a set limit, the temperature trip relay breaks the connectivity between load control circuit and the load resister, wherein a buzzer is activated if the temperature goes beyond a set limit.
Furthermore, in one of the embodiments, maximum power of a solar panel is measured by controlling load control circuit with control knobs and viewing the meter, wherein the device is incorporated with a micro controller and related components so as to automatically obtain maximum power condition, wherein manual operation is an optional mode of operation.
In another embodiment, for measuring short circuit current, a switch marked as ‘short circuit current’ is made ON, and with this, terminals of the solar panel are shorted with each other through a shunt and voltage across the shunt is used as an input to a current measuring module, which receives working supply from stored energy of capacitor.
Referring to figure 1, The enclosure used, is a plastic box, in which, there is a rubber gasket placed between the bottom bucket and the top lid, making it water resistant when top lid is closed, latched and the rubber gasket is pressed. The enclosure is shown as .
Apart from top lid, there is a top plate, placed at top of the bottom bucket. Some of the components are mounted on the top plate, most of which are used for operation of the device and so are required to be accessible and visible to the operator. Top plate components are shown as , wherein other components are placed inside the box and are shown as .
The components are connected with each other as per their purpose and functionality to achieve the overall objective of the device. Power current carrying connections are shown with bold solid lines and arrows. Current carrying connections, which shall be active while 'Short Circuit Current' measurement are shown with bold dotted lines and arrows. 12 V DC connections, which are used for auxiliary supply and for control commands, are shown with thin solid lines and arrows. Very low voltage connection, which shall be used as analogue signal from Temperature sensors to Temperature Control Module (6), is shown as thin dotted lines / arrows.
In the present invention, referring to figure 2, solar panel (13) under test is connected to terminals provided at the Solar Panel performance monitoring device through flexible cables and as soon as the main switch (15) is switched ON, the Solar Panel (13) gets connectivity, through fuse (7), up to the DC power meter (16), which measures & displays the 'open circuit voltage' of the panel (13), wherein the module shows DC power and DC current as zero, because load switch (11) is OFF and no power is being drawn from the solar panel (13), wherein the DC DC converter (5) is not connected with the Solar Panel (13) and 12V DC voltage is not produced, and the cooling fan, ‘temperature control module (6)’, ‘metering & display module (3) for short circuit current’ and other components remain idle.
In accordance with another embodiment of the present invention, referring to figure 3, there is provided a method of measurement of 'Maximum Power' and set of points on IV by solar panel efficiency meter (SPEM), comprising the following steps: `
1. A solar panel (13) delivers different power to loads (1) having different resistances, wherein said panel delivers its maximum possible power to a load resistor (1) if the resistance of the load is equal to the resistance decided as per IV characteristics of the panel (13).
2. Here, to get maximum power from a solar panel, instead of connecting different loads or connecting a variable resistance, a fixed resistor with an ‘Electronic Power Control Circuit (9)’ is connected, which acts as a variable resistor.
3. After measurement of ‘Open Circuit Voltage’ load switch (11) is turned ON.
4. DC-DC converter (5) is connected with the Solar Panel (13) and 12V DC voltage is produced, wherein the cooling fan (1) and ‘temperature control module (6)’, gets 12V DC supply, for enabling running of the cooling fan (1) and capacitor (8) is charged, wherein temperature control unit (6) measures and displays temperature, which extends 12V DC signal to operate the relay, if it finds temperature with in the set limit.
5. Relay (10), if ON, extends connectivity of solar panel power up to ‘Electronic Power Control Circuit (9)’ (EPCS).
6. The heating element (1) consumes power of the solar panel (13), which in return raises the temperature, wherein Cooling fan (1) tries to lower the temperature of the heating element (1).
7. EPCS (9) produces 5V DC, which reaches up to ‘Power Control (17)’ through 3 Nos potentiometers.
8. As per position of potentiometers, a part of 5V DC is returned to EPCS (9), according to which, EPCS (9) allows power to flow from the relay (10) to the heating element (1).
9. Let 3 potentiometers (PTs) are marked 1 to 3 from right to left. Initial PT1 and PT2 are kept at minimum. PT3 is kept at centre. PT 1 gets full 5 V from EPCS. At first, with movement of PT1, maximum power condition is achieved. It acts as ‘sensitivity’ setting. As per position of PT1, a fraction of 5V is available to series of PT2 and PT3. Then, with movement of PT2, maximum power condition is achieved. PT2 acts as ‘coarse’ setting. Then, with movement of PT3, maximum power condition is achieved. PT2 acts as ‘fine’ setting. Below: RED = PT1, YELLOW = PT2 AND BLUE = PT3.

10. ‘Maximum Power’, ‘Current at maximum power’ and ‘voltage at maximum power’ are recorded.
11. Different points of IV characteristic of the solar panel are also obtained with potentiometer control (17).
12. Optionally, instead of using ‘Power Control (17) (Through 3 Nos potentiometer), maximum power is searched automatically using a micro control.
13. Load current range switches (12) can be used in selected range, wherein the switch 1 & 2 short a part of the load resistance, so that current increases with the same voltage of the solar panel (13).
14. 12 V DC supply from DC-DC converter (5) is available at terminals 1 & 2 (positive and negative respectively) of ‘Capacitor (8) (with related circuit made of diode, resistor)’ section. Capacitor (8) gets charging through a series of a resistor and a diode.
15. DC voltage is build up across the 2 Nos parallel capacitors (8) and is available at terminals 3 and 4. When short circuit current test (4) is being carried out, supply is not available at 1&2, but due to stored energy in the capacitor (8), supply is available at 3&4.

In accordance with another embodiment, referring to figure 4, short circuit current is measured by switching on the ‘Short circuit current switch (4)’, wherein the two terminals of the solar panel (13) are shorted and “Short circuit current” flows through ‘main switch’ (15), ‘fuse (7)’ and ‘current shunt (2)’, wherein ‘Metering and display module (3) for short circuit current’ gets a voltage from the shunt (2) which is proportional to the current, wherein when the ‘Short circuit current switch (4)’ is turned ON, the two terminals of the solar panel (13) are shorted and ‘Short circuit current’ flows, wherein another pair of ‘Short circuit current switch (4)’ extends 12V DC from ‘capacitor (8)’ to ‘Metering and display module for short circuit current’, which starts measuring and displaying the short circuit current.
While the invention is amenable to various modifications and alternative forms, some embodiments have been illustrated by way of example in the drawings and are described in detail above. The intention, however, is not to limit the invention by those examples and the invention is intended to cover all modifications, equivalents, and alternatives to the embodiments described in this specification.

The embodiments in the specification are described in a progressive manner and the focus of description in each embodiment is the difference from other embodiments. For same or similar parts of each embodiment, reference may be made to each other.

It will be appreciated by those skilled in the art that the above description was in respect of preferred embodiments and that various alterations and modifications are possible within the broad scope of the appended claims without departing from the spirit of the invention with the necessary modifications.

Based on the description of disclosed embodiments, persons skilled in the art can implement or apply the present disclosure. Various modifications of the embodiments are apparent to persons skilled in the art, and general principles defined in the specification can be implemented in other embodiments without departing from the spirit or scope of the present disclosure. Therefore, the present disclosure is not limited to the embodiments in the specification but intends to cover the most extensive scope consistent with the principle and the novel features disclosed in the specification.
, Claims:We Claim:
1. A performance monitoring device for solar panel(s) (13), comprises of:
a solar power input connection terminal;
a metering module (16) configured to measure and display value of one or more electrical parameters;
an electronic control circuit (9) connected to a load resistor (1) for controlling the magnitude of voltage load at the load resistor element (1) with the help of one or more potentiometers (17);
DC-DC converter (5) for functioning auxiliaries at its prescribed voltage,
wherein said metering module (16) displays maximum obtainable power from the solar panel (13) by varying voltage to be applied at the load resistor element (1) by way of the one or more potentiometers (17).
2. The device as claimed in claim 1, wherein said electrical parameters include but not limited to maximum power (Pmax), short circuit current (Is), maximum voltage (Vmaxp) and current (Imaxp) at maximum power, power output efficiency of the solar panel (13).

3. The device as claimed in claim 1, wherein said power output efficiency of the solar panel (13) is calculated based on the irradiance available due to sun on the solar panel (13) at the time of efficiency measurement.

4. The device as claimed in claim 1, wherein said device is designed to display temperature of the load resistor element (1) on its front interface with the help of temperature sensors coupled to the load resistor element (1).

5. The device as claimed in claim 1, wherein said device comprises of a temperature controller (6) for monitoring the temperature of the load resistive element (1) of the device and configured to automatically switch off the device with the help of a relay (10) in exceptional circumstances.

6. The device as claimed in claim 1, wherein said device comprises of one or more capacitors (8) connected with the DC-DC converter (5) for storing energy and supply it as auxiliary supply for measuring short circuit current in case when solar panel (13) is unable to provide any power supply.

7. A method for monitoring performance of solar panel(s), comprises:
receiving power from the solar panel (13) at a solar power input connection terminal;
controlling magnitude of voltage to be supplied to a load resistor element (1) by varying voltage at one or more potentiometers (17); and
obtaining maximum power obtainable from the solar panel (13) for calculating the actual working efficiency of the solar panel (13) based on the irradiance available due to sun on the solar panel (13) at the time of efficiency measurement.

8. An efficiency measuring device for solar panel(s) (13), comprises of:
a solar power input connection terminal;
a metering module (16) configured to measure and display value of one or more electrical parameters;
load resistor element (1) controlled by a control switch, and provided with one or more tapping means (12) enabling power selection in a range, and connected to a DC-DC converter (5) for functioning at its prescribed voltage;
an electronic control circuit (9) connected to the load resistor (1) for controlling the magnitude of voltage load at the load resistor element (1) with the help of one or more potentiometers (17); and
one or more capacitors (8) connected with the DC DC converter (5) for storing energy received from the solar panels (13),
wherein the device utilises the stored energy in the capacitor (8) for the measurement of said one or more electrical parameters without requiring any external power source.