Solar street lights are now a very popular product, especially in rural areas. They're increasingly being installed on streets. You can often see them turning on at dusk and off at dawn. However, some people may have questions about how these solar street lights work. I'll explain these questions later, especially the question this netizen raised.

About the Working Principle of Solar Street Lights
Before delving into their workings, let's first understand the components involved: solar panels, poles, lamp heads, batteries, and controllers. The operating principle is that solar panels generate electricity, which is then stored in batteries. The controller then controls the lights' operation at night. The controller is the core of the system and has many functions. First, it controls the battery charging, and second, it controls the lighting. This on/off function can be controlled by timers, which require manual setting, with different timers for different seasons. Another method is to use light control, controlling the lighting of streetlights based on the degree of darkness. This control method requires no human intervention and is self-controlled.

Why do streetlights continue to shine during the long winter?
The question here is, is there no sunlight in winter? This is clearly a misunderstanding. Winter doesn't mean there's no sunlight every day. There may be periods of a week where the sunlight isn't very bright, but there is still some light, albeit a tiny amount. However, for photovoltaic panels, power generation isn't the most important factor. At noon on a sunny day, photovoltaic panels often generate the least power. The reason for continuous light generation depends on the overall configuration of the solar streetlight.
① Battery Configuration: Solar streetlights can operate at night, and their electricity is supplied by batteries. This can be simply understood as a battery charging during the day and using the power at night. The battery capacity directly determines the duration of the light. This is relatively easy to understand: the battery's capacity directly determines how long the light lasts. The typical battery configuration is designed to keep the streetlight operational even in rainy conditions for four consecutive days. This is the battery configuration for a typical streetlight.
② Solar Panel and Lamp Head Configuration: The most obvious components of a solar streetlight are the solar panel and lamp head, which is why it's called a solar streetlight. The solar panel primarily charges the battery, while the lamp head primarily consumes the battery's energy. This requires a balanced calculation. The height of the lamp head is directly proportional to the brightness. Generally, a taller lamp head generates more power, which in turn requires a larger solar panel and, consequently, a larger battery. A typical streetlight pole height of 4 or 6 meters is common.

In summary: Whether a solar streetlight can operate normally during the long winter depends primarily on the charge status of the battery and solar panel. In winter, even with a little light, the solar panel can generate power, albeit at a lower level, not completely inactive. Generally, the battery can operate continuously for four days. However, in some special environments, the battery life can be extended. This can be designed based on the actual usage environment.