Solar street light is a typical independent photovoltaic power generation system. This is only one aspect of the problem. What is more serious is that it is also a seasonal load that increases with the decrease in solar radiation. From the above analysis, we can see that the annual winter solstice is the time when the solar radiation is the least, that is, when the solar cell module generates the least power. The winter solstice is the shortest day and the longest night, and the road lighting takes the longest time. .
At present, in the design of solar street lights, everyone is concerned about the lighting problem of continuous rainy days. In fact, this problem is relatively easy to solve. It is enough to increase the capacity of some batteries. If the road lighting indicators on the winter solstice meet the national standards Requirement, unless the power generation of solar cell modules in spring, summer and autumn is sacrificed, there is no other way. The efficiency of the system will be very low at this time.
Under the circumstance of certain solar cell power and light source efficiency, there are many factors that affect the use effect of solar street lights: solar radiation intensity, the reasonableness of the inclination angle of solar cell components, the environmental temperature, the degree of old and new batteries (charge and power generation of new and old batteries) The efficiency can differ by more than 30%) and so on. It is not accurate to evaluate the effect of solar street lights before these conditions are determined.
(1) The road illuminance required by the urban road lighting design standards. In some cases.
The output power of the light source can vary with the voltage of the battery. The lower the voltage, the smaller the output power and the smaller the illumination. Solar street lights using LEDs as the light source are particularly obvious, and their characteristic is to allow normal operation within a very wide voltage range, but in this case, the power of the light source is already very small, and the luminous flux also decreases. This is also one of the reasons why many people report that the use of LED to make solar street lights is good.
(2) The charging and generating efficiency of the new battery can reach 90%.
The power generation efficiency of the old battery is below 70%, the difference between the old and the new can reach 20%, and the temperature has a great influence on the efficiency of the battery. The conditions under which we carry out product acceptance is very worthy of study and attention.
(3) The luminous efficiency of the light source also has attenuation, especially LED.