What type of solar panel should I purchase?

To answer this question, the consumer should first be aware of the different types of solar panels and the advantages and disadvantages of each…

There are three main types of solar panels in use today for residential and commercial projects.

The most prevalent technology is silicon based, either mono crystalline or poly crystalline. As the names imply, mono and poly crystalline refer to the construction of the individual solar cells. Mono means that the cells are constructed from single crystal silicon vs poly which means that many fragments of silicon were melted together to make the cell.

Mono crystalline usually has the advantage of being more efficient and requires less space for the same power as a poly crystalline module. Most aesthetic conscious consumers tend to slightly favor the mono crystalline panels because of the darker colors available and less contrast with the roof surface. While poly crystalline modules are slightly larger and less efficient, they are more economical. They also tend to have a bluish color and may not blend in as well on the roof.

A third type of solar panel that is not used as commonly except in large utility scale solar farms is thin film solar. Thin film solar is manufactured from other elements and contains different light utilization properties that can be more advantageous in low light conditions. Thin film also does not usually suffer as much from the initial light bath that causes degradation in silicon based panels (light induced degradation). Thin film also has the advantage of being more flexible and can be used in more applications than silicon based technology. The main disadvantage of thin film is the lower efficiency and typically higher price tag. Thin film requires significantly more space for the same power rating as a typical silicon based system.

Your solar sales representative will help you select the right technology for your application and budget.

Modules:

Type
Poly crystalline
Mono crystalline
Thin film, amorphous
BIPV (building integrated photovoltaics)

Power Class  (DC Watts)
60 cell: 260 to 365 watts dc
72, 90, 128 cell: solar panels up to 430 watts dc

Efficiency
Ratio of module power output (actual)  and available power (solar irradiance).
Range between 16%-22%  Ex.   300W / (.8 x 2000 W/m2) = ~19%

UL 1703 Standard
Impact testing:  Hail, modules are tested for 1” hail @ 52 mph
Load Testing:  Wind loading & snow loading tolerances
Electrical Testing:  Characteristics & temperature tolerances
Fire Testing

Solar panels can also come in different colors, sizes and weights.