Solar street lights are a great way to reduce your energy consumption and save money on your electric bill. They are also relatively easy to install and maintain. However, designing and calculating solar street light systems can be a bit tricky. 

In this article, we’ll walk you through the process of designing and calculating a solar street light system.

Firstly we need to do is analyzing various factors that affect the configuration of a solar street light. Then calculate the actual configuration of solar street lights according to the installation site situation. When designing a solar-led street light, the daily power generation and electricity storage are generally calculated according to the power consumption of the street lights, and finally, a scientific and reasonable configuration is provided for the user. 

How to design and calculate a solar street light system?

Step 1. Determine the pole height as per the road width that will be illuminated. 

We can roughly work out the required pole height as per the following formula :

Pole Height (m)=Road Width(m)/(1.1~1.3) 

Eg: If the road width is 6m, then the pole height can be 6/1.1=5.5m,6m/1.3=4.6m, and the pole range from 4.6 to 5.5m is suitable for this road.

Step 2. Determine the illumination as per the road lighting standard requirement. 

Road lighting standards requirements: The highway average illumination 20lx, uniformity of 0.4, the trunk road average illumination 15lx, evenness 0.35, sub-distributors average illuminance 8lx, uniformity of 0.35, bypass road average illuminance branch 5lx, uniformity of 0.3. 

Step 3. Determine the amount of power you need for your solar street lights. This will vary depending on the illumination of the led lights you’re using.  For the SLD’s SLX All In Three solar street light with high brightness led chip can give a maximum of 180lm/watt, if you want to get 10000lm, the led work power is just needed at 60W. 

Step 4. Following you need to calculate the amount of time that the solar street lights will need to be turned on each day in order to provide sufficient lighting.  The SLX all in three solar street light typically work in the timmer dimming mode :

1hours 50% 

5hours 100%

6hours 50% 

6hours+6hours/2=9hours,  the led lights work time at 100% brightness equal to 9hours.  

Step 5.  Work out the power consumption, that equal to led power by work hours. eg. 60W*9hours =540WH. So the power consumption requested each night is 540WH. 

Step 6. Sizing the battery capacity as per the backup days. Nowadays, the most solar controller is intelligent and automatically decrease work power as per the rest power in the battery and the backup days you set.  

Though the lithium battery can be with 100% DOD, in order to prolong battery lifespan, we suggest keeping DOD at 80% or less. So the battery capacity can be 1.5times of power consumption each night. Eg.: 540WH*1.5=810WH

Step 7.  Sizing the solar panels. The solar panels will need to be able to provide enough power to keep the batteries charged, so it’s essential to choose panels that are large enough to meet your needs.  

When you size the solar panel, the solar radiation in the installation location is another essential factor you need to take into consideration.

Take the 100w solar example, it generates 0.55kwh every day in Nigeria, while only 0.35kwh in Guangzhou, China. 

So it requested to equip bigger solar panel for the low solar radiation area.

  
Conclusion

Once you have all of this information, you can design and calculate solar street light power systems. You might be a bit tricky when you begin purchasing for solar panels and batteries. If that, don’t worry about that, that’s where we come in, you don’t need to connect with different suppliers, we will do the job for you and assemble the products here.