Solar Light TowersSimon
Solar panels for hybrid light towers:
Hybrid light towers use solar energy as an alternate energy supply method. The solar panels are used to store energy in batteries, from where the energy is further distributed to various components of the light tower as per the requirements.
A 350 W solar panel will produce 1400 Wh or 1.4 kWh of energy in 4 hours under direct sunlight (350W * 4h = 1400 Wh). This means that it can fully charge one battery of 120 Ah/12 V (1.44 kWh) in about 4 hours. Four such solar panels can charge four batteries (1.44 kWh each) in about 4-5 hours to get 5.76 kWh of energy.
Panel Sizing for Led Light Tower
The solar panel sizing and battery sizing has to make sense because it is required to have at least one full charge of batteries in about 5 hours of direct sunlight so that all of the energy stored in batteries can be utilized during the night time operations. If the solar panels are of a lower wattage than required, the battery capacity will not be fully utilized, which will reduce the operating time of the light tower. Since the energy acquired by solar panels is limited by the number of hours of direct sunlight (about 5 hours), the selection of batteries and solar panels should be made accordingly.
For example: A 200 W solar panel would produce 1000 Wh of energy (200 W*5h = 1000 Wh) in 1 day (considering 5 hours of direct sunlight). So a 24V battery should have a 41.67 Ah capacity.
The solar panel will need to have a charge controller in order to protect batteries from overcharging. The charge controller regulates the voltage and current coming from solar panels to the batteries hence preventing failure of battery due to overcharging.
In conclusion, solar panels and batteries should be selected carefully keeping in mind the requirements and the limitation of the number of hours of direct sunlight.