In several municipalities, street lighting projects account for almost half of the total electrical expenditure. Apart from the energy bills, maintenance and replacement of the metal halide street light have been posing additional expenses and traffic disruption. LED street light with solar panel does not rely on electric power, as well as can save millions of dollars in maintenance and electricity costs.
In spite of the possibilities of the LED street lights with solar panel, unlike the traditional alternatives, they are not common because of their prices. Nevertheless, since the world is interested in greener and cleaner alternatives, solar LED street light with solar panel to continue being advantageous from technological advancement as far as the field of semiconductors is concerned because this is what brings about the cost-effective implementations.
In as much as the sun is known for radiating up to 1000 Watt in a square meter, LED street light with solar panel can convert just about 30% of the irradiant energy. For the efficiency of the street light to be increased, there is a need for storing the converted energy in a battery, and the use of traditional charge controllers can bring about more conversion losses. Since solar panels are known for being a p-n junction, they will not operate like perfect power sources.
Rather, the solar panels have an operating point that power is produced at its maximum. Any movement from the operating point will decrease the effectiveness of the LED street light with a solar panel. For all energy that the solar panel can deliver to be extracted, the Max Peak Power Point is needed. The fact that the Max Peak Power Point relies on the amount of solar energy and the solar panel’s temperature, the Max Peak Power Point ought to constantly adapt to maximizing conversion of energy.
Because of the solar panel’s characteristics, the delivered current will remain steady. As soon as the operating voltage passes, the current will start falling dramatically. At a specific point, the energy being produced by the solar panel is always at highest. When a traditional controller that does not have the Max Peak Power Point is used to charge a solar battery of 24 V, the operational voltage of the LED street light with the solar panel will be forced to the solar battery voltage. Consequently, this set up will produce power, which is about 140 W.
On the other hand, at the knee point, the Max Peak Power Point makes it possible for the LED street light with a solar panel to operate in a way that the power being produced will be equal to 215 Watts. In this case, the Max Peak Power Point system increases the amount of power being produced by about 50%.
Based on factors like the amount of irradiant sunlight, partial shading, and ambient temperature, the location of the knee point of the LED street light with solar panel can change. So, there is a need for settling for a reliable Max Peak Power Point that can regularly update itself for it to work at different ideal points effectively. The Max Peak Power Point is can effectively sense the voltage, as well as to measure the current using a corrective process; hence, making the LED street light with a solar panel to increase its efficiency.
Max Peak Power Point uses DC-DC conversion topology based on differences in the operating voltage between the solar panel and the solar battery. In normal charging conditions, when the voltage of solar panel is greater than that of the battery, there is a need for using a buck topology to increase the efficiency of the LED street light with a solar panel. On the other hand, when the panel voltage happens to be lesser, with reduced current, the boost topology can be used to increase the charging voltage. In both cases, the work of the Max Peak Power Point is to maintain, at the peak point, the current being extracted from the solar panel.
Significance of Solar Battery for Solar Panel
For the efficiency of the LED street light with a solar panel to work effectively, there is a need for the charge controller to consider the kind of solar battery. LED street lighting systems have been using either alkaline or lead-acid batteries since they have high energy density-to-cost ratios. Also, they can effectively work over different ranges of temperature. Therefore, there is a need for continuous monitoring of the batteries as they are being charges to prevent them from overcharging, which can result in explosions or leaks. Likewise, the battery’s overall capacity can be dramatically reduced by undercharging it over extended periods. The inherent capability of the LED street lighting systems to correctly control the electric current to the battery increases the effectiveness of the street lights. It is because of this that Del Illumination exists to offer your assistance in how you can increase the efficiency of your street lights.