There are mainly two types of solar street light designs available in the market now, All In One solar street lights and Integrated solar street lights. The outlook of both these lights can be different but components are the same, i.e., solar panel, battery, LED and charge controllers. Installation of solar street light is quite unchallenged and simpler compared to traditional street lights. However, there are a few things to keep in mind before installing solar lights to receive maximum benefit out of the device.
- Access to sunlight
One of the most important aspects of solar street light installation is the location. The area you want to illuminate should be free of any shade and must have sufficient access to sunlight. This way, the solar panels are able to absorb more sunlight and charge the battery in order to power the LED at night. The position of the sun changes during the day, so before installing the lights, you need to find out the amount of radiation that reaches the selected spot during the day.
If the spot is not ideal for installation, you may move it to a more optimal area or remove the source of shade. If there are trees or shrubs around, you may trim down their branches to let more sunlight enter the spot. Areas that are susceptible to cloudy or rainy weather may experience insufficient battery charge but even indirect sunlight can help to power the lights with a low level of brightness. A tropical area gets more sunny days so the solar street lights will continue to light up for a few days even during rainy weather.
- Research the area
If the lights are placed in an area which is active throughout the night, you need to choose a model that stays on from dusk to dawn. Also, the light should have a battery with higher capacity to light up for long duration. It is better to use integrated solar street lights with no motion sensors in an actively busy area. Modern solar street lights using motion sensors and adaptive lighting techniques to save more energy can be useful in public streets that are less active or private residential properties.
It is always better to understand your area of installation and adjust the solar lights accordingly. If you use the solar street lights with adaptive lighting techniques, the cost of the overall solar project can be significantly lower. Depending on the overall size of the area, you can choose the total number of street lights needed and depending on the brightness required for the area, you may also choose the lumens and watts of your LED and panels respectively.
- Lighting requirements
Solar street lighting can be used for both public and private lighting needs. The area determines how strong the LED lights should be. Before installing solar street lights, you need to check the size and space of the area. In a private property, solar street lights are mostly used for adding beauty to the landscape or to light up the dark corners of the property to bring in a sense of safety.
Public roadway lighting or park lighting requires multiple lights and must be placed 10 to 15 meters apart from each other. If there are any obstructions like buildings or trees, you will be suggested to increase the density for better lighting. Stronger or less potent LED lights will be used depending on the size of the area. A solar lighting professional will be able to help you understand the efficiency of the selected area.
- Height and distance
Once the area of installation is finalized, next step is to determine the height and distance of the solar street light installation. As mentioned earlier, normally the street lights are placed at a distance of 10 to 15 meters. The suggested installation height of poles is 8 to 9 meters on a main street, 4 to 5 meters for park and path way lighting, 15 to 20 meters for lighting stadiums.
Default height of a pole may not be suitable in all areas. Sometimes you may have to cut down the tree branches obstructing sunlight and if you do not want to disrupt a beautiful tree line, you may arrange for the panel to be raised above it without having to cut down the trees. Windy areas will need specialized poles to withstand the force of wind. You may increase or adjust the height of the pole to get sufficient light. Also, you may discuss your unique requirements with your dealer while purchasing the lights.
- Brightness, lighting time
After the installation height of the lights is determined, it is easier to set the LED power accordingly. Solar panel power and battery capacity are set according to the LED power and total lighting time. Rural areas with little activity in the night, lights with motion sensors or lights that dim the brightness after a certain number of hours can be used to save the energy. Motion sensors will help you in saving energy and lights with motion sensors are typically used in private properties or paths that are not very busy at night.
Lights with motion sensors detect movement nearby and light up in 100% brightness and if no activity is detected, dim down to 20% brightness. Integrated solar lights without motion sensors work in full brightness for the first four hours of the night and then in 20% to 30% brightness. This is suitable for streets where there is heavy traffic in the first few hours of the night.
- The quality of the material
Quality of a solar lighting system majorly depends on the quality of the solar panels. Mono-crystalline solar panels or poly-crystalline solar panels are used for solar lighting. Mono-crystalline has a better conversion rate and performs better in cloudy days; however, poly-crystalline solar panels are affordable and commonly used in solar street lights. Around 25 years to 30 years of warranty is promised for solar panels depending on the brand.
For modern solar street lights, lithium-ion or LiFePO4 batteries are used. Compared to lead acid batteries, the lithium batteries have longer cycle life and they charge faster. They require no maintenance like lead acid batteries. Due to their compact size, they need only smaller-sized solar panels to function and can withstand extreme weather conditions.
MPPT or PWM controllers are used in solar street lighting. Even though MPPT controllers are more expensive, they perform much better than PWM. However, considering the cost, they are not ideal for all solar outdoor lighting projects. Controllers are an essential part of a solar lighting system to prevent overcharging and help in extending the life of the batteries.
LED is the main light source for solar street lights as it is energy saving. LED emits zero UV rays and delivers much higher lumens using less energy than traditional lighting solutions. You need to discuss with your dealer regarding luminosity per watt, light distribution pattern, watts needed to meet your requirements and specific luminosity area.
The solar street installation is quite easy but if we do not do it as per the manufacturer’s guidelines, the solar street lights will not work very well. At the time of installation, ensure that there is no shadow falling on the solar panel. The panels also need to be tilted at an angle and fixed in a direction so that maximum direct sunlight falls on the panels. Avoid installing solar street lights next to any other bright light source. It is always better to have a professional handle the installation of your solar street lights; however, if you would like to do it yourself, read the user’s manual carefully and you can do the installation with minimal labor and tools.
The investment towards solar street lights is much higher compared to traditional street lights. Nonetheless, in the long run, considering the electricity, operational and maintenance costs, the actual cost of solar street lights is relatively much lower. Have an open discussion with your dealer regarding your lighting requirements and your budget, who will be able to suggest the best cost-effective solar street lighting options suitable for you.