In order to deeply understand the discharging time of solar street lights, we first need to jump out of the inherent cognition of traditional street lights, and make clear the unique working mechanism of solar LED street lights — only by mastering its energy conversion and control logic can we clearly grasp the core factors affecting the discharging time of solar street lights to make this green lighting device truly advantageous. Only by mastering its energy conversion and control logic can we clearly grasp the core factors affecting the discharge time of solar street lights, so that this green lighting equipment can truly play its advantages.
solar led street lights
While traditional street lights rely on the grid for power supply, require complex cable laying and consume utility power for a long time, solar street lights realize autonomous lighting through the conversion of “light energy – electricity – light energy”. The solar street light system consists of four core components: solar panel, rechargeable battery, intelligent controller and LED light source, of which the controller is the “brain” of the whole solar street light.
At dawn every day, the ambient light is enhanced, the solar panel converts the light energy into electricity, and at this time, the voltage generated exceeds 5V, the controller immediately sends a signal to the LED light, so that the solar LED street light is automatically turned off; at the same time, the electric energy is guided to the storage battery to store, and to prepare for the nighttime discharging.
Battery capacity is the most direct factor determining the discharge time of solar street light, the higher the capacity, the longer the discharge time of solar LED street light. From the practical application point of view, the shortest discharge time of ordinary solar street lights is about 12 hours, which is suitable for areas with low demand for nighttime lighting, such as solar street lights next to the neighborhood walkway. The solar LED street light equipped with high-capacity batteries, discharge time can reach 40 hours, this kind of solar street light is designed to cope with special weather — winter light is weak, rainy season continuous cloudy days, solar panel charging is insufficient, high-capacity batteries to ensure that the solar LED street light is not “break light”, continue to play the role of lighting.
Therefore, when purchasing solar street lights, you need to pay attention to the battery type and capacity in conjunction with the usage scenarios to ensure that the solar LED street lights can support sufficient lighting hours, especially in rainy and cloudy areas, you should prioritize the solar street lights with high-capacity batteries.
The brightness of solar LED street light is obviously inversely proportional to the discharge rate of the battery, the higher the brightness, the faster the discharge rate of solar street light and the shorter the discharge time. This law is similar to the screen of a cell phone: high brightness of the screen consumes electricity quickly, and high brightness of the solar LED street light consumes electricity quickly. Take the solar street light equipped with 100Ah battery as an example, if the brightness is adjusted to 100% to meet the peak hour lighting demand of the main road, the discharge time of the solar LED street light is about 18-20 hours.
If the traffic flow is reduced at night, the brightness of the solar street light will be reduced to 70%, the discharge time can be extended to 26-28 hours; further reduced to 50% brightness, the solar LED street light discharge time can reach 35-38 hours. Nowadays, most of the intelligent solar street lamps will be equipped with brightness self-adaptation function, which automatically adjusts the brightness according to the time of the day, not only to ensure the lighting effect of the solar LED street lamps, but also to prolong the discharge time to avoid excessive consumption of the battery.
Whether the installation is standardized or not will indirectly change the discharge time of the solar street light by affecting the charging efficiency of the solar panel. With standardized installation of solar street light, the solar panel can receive sunlight at the best angle. The best installation angle for solar panels in high latitude is +10° local latitude, and low latitude is -10° local latitude, such an angle allows solar panels to absorb light energy efficiently and provide sufficient power for the batteries, thus guaranteeing the discharging time of the solar LED street light.
solar led street lights
If there are defects in the installation, for example, if the angle of the solar panel deviates too much, the daily charging capacity of the solar street light will be reduced by 20%-30%, the battery cannot be fully charged, and the discharge time of the solar LED street light will naturally be shortened; in addition, problems such as loose circuit connection and inadequate waterproof treatment may lead to slight leakage of the solar street light circuit, and even if there is only a leakage of 5% every day, the cumulative amount of the circuit over a long period of time will also reduce the effective discharging time of the solar LED street light significantly. Even if the leakage is only 5% per day, the long-term accumulation will significantly reduce the effective discharge time of the solar LED street light, and in serious cases, even due to short-circuit, the solar street light battery will be “instantly discharged”, and the lighting will not be available on the same day.
The demand for solar street lights in residential areas is “balancing illumination and energy saving”, with nighttime illumination needing to cover the period from 18:00-23:00 (approx. 5 hours), and redundancy for cloudy days needing to be set aside. It is recommended to choose the solar LED street light with 12-18 hours discharge time, with 60-80Ah battery, and set the brightness at 80-100% (about 80-100W) – this solar street light can not only meet the demand of residents’ night walks and vehicular traffic, but also won’t cause light pollution due to high brightness, and 12-18 hours discharge time can be used to cover 18:00-23:00 (about 5 hours) at night, and redundancy should be reserved for cloudy days. 18 hours of discharge time can cope with 2-3 days of cloudy days, avoiding the frequent “cut-off” of the solar street light affecting the life of the solar street light.
Rural roads generally lack of grid coverage, traditional street light installation cost is high, solar street light becomes the best choice. Rural night lighting demand is concentrated in 17:30-22:00 (about 4.5 hours), but short light and cloudy days in winter, stronger endurance is needed. It is recommended to choose solar LED street lights with 24-30 hours of discharge time, equipped with 100-120Ah batteries and 70-90% brightness (about 70-90W): 24-30 hours of discharge time can cope with 3-5 days of cloudy days, ensuring that the solar street lights can still be illuminated when there is no sufficient light; 70-90% brightness balances clarity and energy consumption, avoiding solar LED street lights from discharging too quickly. 70-90% brightness balances clarity and energy consumption to avoid solar LED street light discharging too quickly.
Urban main road has high traffic flow at night, which requires high lighting duration and brightness of solar street light, covering 17:00 – 6:00 the next day (about 13 hours), and need to deal with extreme weather. It is recommended to choose the solar LED street light with discharge time of 30-40 hours, with 120Ah or above battery, and keep the brightness at 90-100% (about 100-120W). 30-40 hours of discharge time can cope with 5-7 days of cloudy days, and ensure that the solar street light won’t interrupt the illumination on days of rainstorms and blizzards; the high brightness meets the demand of vehicle traffic, and at the same time it can be equipped with intelligent adjustment function, and the brightness can be reduced to 70% after 2:00 am, and the brightness can be reduced to 70% after 2:00 am. Meanwhile, it can be equipped with intelligent adjustment function to reduce the brightness to 70% after 2:00 a.m., which further extends the discharge time of the solar street light.
solar led street lights
Dust and leaves accumulated on the surface of the solar panel will block the light, resulting in a decrease in the charging efficiency of the solar street light – experiments show that 5mm thick dust will reduce the charging efficiency by 15-20%, which will indirectly shorten the discharge time of the solar LED street light by 3-5 hours. Indirectly shorten the discharging time of solar LED street light by 3-5 hours. It is recommended to clean the solar panel every 1-2 months, wipe it with a soft cloth dipped in water (avoid corrosive detergents), and clean it in time after sandstorms and haze to ensure that the “energy source” of the solar street light is unimpeded.
Battery is the core of solar street light discharge, capacity decay and leakage may occur after long-term use. It is recommended to check the solar street light battery every six months: observe whether the shell is bulging and leaking, if there is any problem, replace it in time; check the voltage through the controller, the normal voltage of 12V battery is 12.5-13.5V, lower than 12V means the capacity is declining, need to be maintained or replaced. The low temperature in winter will reduce the activity of the battery, you can parcel waterproof insulation cotton on the outside to reduce the impact of low temperature on the discharge time of the solar LED street light.
Controller parameters directly affect the charging and discharging logic of solar street light. The solar street light “start voltage” can be fine-tuned to 4.8-5V to avoid dusk voltage fluctuations that cause the solar LED street light to turn on early; set the “segmented light mode”, such as 18:00-22:00 high brightness, 22:00 – 6:00 low brightness the next day, and 18:00-22:00 low brightness the next day. 6:00 next day to reduce power consumption. It should be noted that the parameter adjustment should be operated by professional personnel to avoid the failure of solar street light system.
From traditional street light to solar LED street light, the innovation of lighting equipment is not only the switch of energy, but also the upgrade of efficiency and environmental protection. The discharge time of solar street light is not a fixed value, but is determined by the battery capacity, brightness and installation quality, which needs to be adapted to the scene and extended through maintenance. Whether it is the basic lighting of residential area or the high demand lighting of urban main road, solar street light can meet the demand through scientific configuration.
