Solar Street light is one of the major trends in the solar industry, more cities, towns, and municipalities are adopting this technology as they try to go green or reduce expenses attached to traditional lights. Giving all the rave about solar street light, it will make sense to give a breakdown of this wonderful piece of technology.
We take a crucial look at the solar light components to know why its demand in the market is on the rise.
About Solar Street Light: The Main Components
- Monocrystalline Solar Panel
The solar panel is a key component of solar street light and there are two main types used majorly in the solar industry, they are the polycrystalline and monocrystalline solar panels. The mainly used panel is the market is the monocrystalline solar panels due to the fact that they offer better performance with higher conversion rates than polycrystalline panels. As a result, monocrystalline solar panels are used in a solar street light.
- Light source: LED
LED is a popular source of lighting in solar street lights due to its higher efficiency and lower energy consumption as well as a longer lifespan. It can vary in watts and sizes to fit into various applications. Additionally, heatsink often accompanies LED components and it is fixed to the rear side to assist in dispelling the heat produced by the use of LEDs to ensure it has a longer lifespan.
- Deep-cycle Battery
The batteries used in solar street lights usually deep-cycle batteries due to their outstanding features such as having way more cycles than typical batteries used in cars, deep discharges, and durable power supply. We have two major types of these batteries utilized in the solar industry, they are the lead-acid and lithium-ion battery
- Solar Charge Controller
Charge controllers are used to regulate the current and voltage generated by the solar panels and prevent the solar batteries from overcharging. We have two main types, which are the Maximum Power Point Tracking (MPPT) and Pulse Width Modulation (PWM) charge controllers.
Mostly MPPT is used in solar lights as PWM is known to waste some of the energy generated while MPPT is able to convert all the generated energy from the panels. Some of the primary functions of an MPPT controller is listed below:
Through the use of the charge controller, you can set the power output using a time schedule, for instance, you can set the brightness to 35% from 10:00 pm to 6:00 am, 100% from 7:00 pm to 10:00 pm or 60% from 5:30 pm to 7:00 pm. Usually, for a controller, there are about five-time settings you can schedule based on your needs. The use of time control is usually combined with the use of motion sensors. For instance, at midnight when the light is set to about 35%, the use of motion sensors can allow the power to be raised to 100% when pedestrian motion is noted. This helps saves energy to extend the lifespan of the solar street light.
- Twilight to daybreak control
Through the monitoring of the solar panel voltage, which is dictated by the sun intensity. The charge controller can detect when the voltage is low during the sunset where the voltage drops below 5v then the controller turn on the solar lights. At sunrise, as the voltage increases beyond 5v, the lights are turned off by the controller.
- Motion sensor control
The motion sensor works by sensing people’s movement, after which a signal is transmitted to the charge controller to increase the brightness of the solar light fixture. When people are in the vicinity of the solar light, the brightness increases and it drops as soon as people have left the area.
Infrared(PIR) motion sensor
A motion sensor is of two main types, which are the microwave and the infrared motion sensor. The microwave sensor acts by transmitting microwave radar and collecting bounced signals to evaluate if there are changes in the received signals. On the other hand, the infrared sensor acts on the detection of heat source movement.
The infrared motion sensor is more preferred to microwave even thou it has a bigger working angle. However, the microwave sensor is very sensitive and highly likely to react to the deceptive movement like fluttering birds or swaying of trees, which could lead to unnecessary consumption of precious energy.
- Avoiding Low voltage disconnect(LVD) and overcharging
One of the main contributors to the shortened lifespan of solar batteries is over-discharging and overcharging. This is basically what solar controllers are there for in solar street light systems to help prevent that from happening thereby extending the batteries’ lifespan.
All these components are what make your solar street lights function as it is, if the solar light system is missing one key piece it could have resulted in the system not working at all or have a serious effect on the performance of the system. Solar street lights can also be combined with other applications such as CCTV or a wireless monitoring system that could the lights to be controlled or monitored from a computer or smartphone.