Solar panels are devices that directly or indirectly convert solar radiant energy into electrical energy through the photoelectric effect by absorbing sunlight. Currently, they are divided into three categories: monocrystalline silicon, polycrystalline silicon and amorphous silicon.
The solar panels used in solar street lights are mainly monocrystalline silicon and polycrystalline silicon. Due to the higher purity of the materials made of monocrystalline silicon, its conversion rate is higher than that of polycrystalline silicon. The conversion rate of monocrystalline silicon is 19%-20%, and the conversion rate of polycrystalline silicon is 17%-18%. Of course, the price of monocrystalline silicon is also higher than that of polycrystalline silicon.
When purchasing solar street lights, should we first consider monocrystalline silicon solar panels?
"What you pay for what you pay for" has always been regarded as the truth. Yes, the price of solar panels with good performance or large size is indeed more expensive. You can buy better products at higher prices, but you should choose when buying street lights. Solar panels mainly depend on the configuration needs, the price cannot be the only criterion for considering the product, more often it is necessary to consider whether it is suitable.
So, how to choose a suitable Solar Panel for solar street lights? A comprehensive analysis must be carried out based on the actual situation.
1 Purchase according to the actual installation area
Monocrystalline silicon has a high conversion rate and stable performance parameters. It is suitable for use in southern regions where there are more cloudy and rainy days and relatively insufficient sunlight; polycrystalline silicon panels have a lower conversion rate and are used in some sunny and sunny eastern and western regions. More than enough. Therefore, if solar street lights are used in places with superior lighting conditions, there is no need to configure monocrystalline silicon panels, which can reduce the cost of lighting to a certain extent.
2 According to the working voltage to choose
The solar panels are arranged in series and parallel. The series affects the voltage and parallel affects the current. The size of the solar panels will vary with the required voltage and current.
The electricity stored in the battery is provided by the solar panel. If the battery is to be charged normally, the operating voltage of the solar panel must be about 1.5 times the battery voltage. If you charge a 6V battery, you need 8V-9V solar panels; to charge a 12V battery, you need 15V-18V solar panels.
3 Choose according to the required output power
The output power of the solar panel is also affected by the size of the solar panel. The output power per unit area of the solar panel is about 127WP/m2. The larger the area, the greater the output power. Generally, the output power of the solar panel should be 3-5 times the power of the light source. Above, it is 3-4 times or more in areas with abundant sunlight and short light-on time, and vice versa.
In summary, there are two points, sunshine and configuration.
Therefore, the selection of solar panels has to be scientifically selected. If you blindly think that the expensive is the best, it will cost more money, especially for some larger projects, because the purchase of solar street lights is in large quantities. The right is the best. Choosing the right battery panel can not only guarantee the quality of the project, but also save the budget.
So, how to choose a suitable 
3 Choose according to the required output power 
