PV Modules

Photovoltaic Modules

A Photovoltaic(PV) module which is generally termed as a solar panel is an assembly of photovoltaic cells electrically connected to each other and mounted on a laminated frame. The solar cells are primarily made up of silicon material which absorbs the photons emitted by the sun. There are three major types of PV modules. Mono-crystalline Poly-crystalline Thin-film Each solar PV module type has its own unique features. These PV modules also vary based on how they are manufactured, their appearance, performance, costs, etc. Like this:Like Loading... Read more

What are the components of a Solar PV Module?

Solar photovoltaics are made with a number of parts, the most important of which are the solar cells which are connected and sandwiched between glass and metal. Major components of a PV module are: Module Frame   Glass Encapsulant Back Sheet Backsheet is a film of that protects the solar cells from severe environmental conditions. A solar back sheet is the last layer at the bottom of the solar PV module and is typically made of a polymer or a combination of polymers. Junction Box                         Like this:Like Loading... Read more

Difference between mono-crystalline and poly-crystalline PV modules

Both mono-crystalline and poly-crystalline solar PV modules have cells made of silicon wafers. To build a mono-crystalline or poly-crystalline module, wafers are assembled into rows and columns covered with a glass sheet, and framed together. Poly-crystalline cells are square-shaped whereas mono-crystalline cells are square with missing corners. While both of these types of solar PV modules have cells made from silicon, mono-crystalline and poly-crystalline modules vary in the composition of the silicon itself. Mono-crystalline solar cells are cut from a single, pure crystal of silicon. Alternatively, poly-crystalline solar cells are composed of fragments of silicon crystals that are melted together in a mold before being cut into wafers. Mono-crystalline modules have better efficiency and power capacity. Like this:Like Loading... Read more

How does temperature affect solar panels?

Solar panels react differently to the operating temperature. The efficiency of a solar panel decreases as it increases above the ambient temperature. Each solar panel has a temperature coefficient (which is defined in datasheet of panels). The temperature coefficient represents the rate at which the panel will underperform at each increase in degree Celsius (°C). Most panels have a temperature coefficient of between -0.2% /°C to -0.5%/°C, when tested under standard laboratory conditions, where ambient temperature is set to 25°C. For example if the temperature coefficient of a particular type of panel is -0.5%, then for every 10C rise, the panel’s output power will reduce by 0.5%. [Source: Youtube] [Publisher: altE Store’s Educational Video Channel] Like this:Like Loading... Read more

What are PV module hot spots, its causes and effects?

Hot spots are areas of high temperature that affect only one zone of the solar panel and resulting in a localized decrease in efficiency, and therefore, lower output power and accelerated material degradation in the area affected by the high temperature. Hot spots are not visible to human eyes and are detected and verified using infrared measurement technique. Above image shows of a solar panel showing a hot spot developed due to bird droppings Causes and its effects The reasons for the appearance of hot spots are multiple and can be classified into functional or operational. Defect severity and remediation actions also vary widely as a result. Functional reasons Cell mismatch: It occurs when cells of different current are connected in series. Cell damage: It occurs during manufacture, due to the fact that the silicon cell will be subjected to a stressful process during rolling, handling and transportation. Operational reasons Seasonal shadows: When cells are completely or partially shaded for a long period of time, it results in increased temperature in the shaded cell and further creates hot spots. The loss in power output due to a hot spot in solar panels is not directly correlated with the area of the panel that is shadowed. Even a small shade can have a significant impact on the output power of the module. Soiling or dirt accumulation: Solar panels become dirty from dust, suspended sand, dirt and other contaminating impurities if not cleaned periodically during their service life. The dust accumulated on the […] Read more

What would happen if the solar panels deployed in the system have different electrical characteristics?

When solar panels with different electrical characteristics, interconnected with each other are deployed in the system, it creates serious power losses & adversely affects the overall energy generation. These losses are referred as “Mismatch losses”. The current (Isc) in the string in which the panels are connected in series with each other, is limited to the lowest output current from any of the panel. Thus mismatch causes the lower output power from the string & the system efficiency and performance becomes lower. Like this:Like Loading... Read more

1 2