Solar equipment derives energy from the sun but they keep on working even during the night. But a person decided to take the initiative in making a solar cell, and it would not be wrong to consider him to be the first person to invent the solar bulb. Though the cell Charles Fritts, an American inventor made in 1883, was not efficient, today solar panels are available with 20% efficiency. You must have noticed that they turn on after the sun sets and turn off by dawn. How does this happen? Today, you will get to know how do solar lights turn on at night. Also, do solar lights need direct sunlight? I wonder how long do solar lights stay on at night? Let’s start finding the answer to all these questions.
What is Solar Light?
It is a solar lamp that consists of an LED lamp that is backed by a battery that works on solar energy. These lights are also known as solar lanterns or solar lamps. Solar light is used for commercial as well as industrial uses. The different types of outdoor solar lights are-
- Ambient and decorative solar lights.
- Solar floodlights
- Solar lanterns
- Solar pathway lighting
- Solar powered-motion lights
- Solar-powered lamp posts
- Solar spotlights
- Solar streetlights
How Do Solar Lights Turn On At Night?
Solar lights have photosensors that enable them to light up at night. Since the term solar is related to the sun, you consider it would work only in the presence of sunlight. But how are they so efficient even when there is no solar energy to power them at night? Solar devices are not designed to just work in the morning, otherwise what use they would be?
Components of Solar Light
Solar light is made up of four main components, namely solar panels (photovoltaic), batteries, light sensors, and control electronics. During the day, photovoltaic cells absorb the sunlight and store it in batteries. This stored energy is converted into electrical energy. Batteries should be of accurate capacity to store enough power during the day so that they can light the bulb for the night.
1. Solar Lights have Photo Sensors
The electric components that can detect sunlight are the photo sensors which act as a link between the batteries and LED lights. When there is no sunlight at night, photo sensors activate the circuit between the light and the batteries. This allows the power to flow to the LEDs, and they light up. In this way, solar lights automatically turn on at night.
2. The Voltage Sensor
Inside the circuit, there is the voltage sensor that reads the voltage as the power generates. Power is developed during the day, then the voltage sensor detects energy and shuts the bulb by breaking the circuit. At the night, the voltage sensor opens the circuit, the current flows and the bulb turns on.
3. A Motion Sensor
During cloudy days and in winter when there is insufficient sunlight a motion sensor prevents the bulb from turning on during the day. It works well in combination with a voltage sensor and a photosensor to detect the energy. This enables the accurate working of solar light in all seasons irrespective of the sunlight. Now, you have figured out how do solar lights turn on at night. But still, there is more to discover.
Also See: Solar Power to Triple During Next Five Years
Do Solar Lights Automatically Turn Off in the Morning?
After learning how do solar lights turn on at night, let’s also see whether solar lights automatically turn off in the morning. Photosensors detect sunlight and cut off the circuit between the batteries and the LEDs. This way solar lights go off automatically. You do not need to worry about turning off the solar lights because they are designed intelligently to work out everything by themselves.
Why Solar Light Remains on During the Day?
Sometimes it happens that the sun is on its head and solar lights are still on. It means that the photo sensors are not working properly. Either they are broken or there is some technical fault. In this situation, photo sensors do not detect the presence and absence of sunlight. Therefore, they are always on. This can be fixed by replacing the photo sensors easily at home.
Types of Photo Sensors
Different types of photo sensors are used for solar lights. The most common photo sensors used in solar lights are as follows:
a) Light Sensors: It is a simple sensor that senses the absence of sunlight in the evening or night and turns on the solar light. They do not differentiate between the intensity of darkness to adjust the on/off timings.
b) Lux Sensors: It is designed to detect the intensity of darkness after sunset to turn on the solar lights. It works on the intensity of light and not just the presence or absence of sunlight.
c) Passive Infra-Red (PIR): In motion-detecting and security solar lights, this type of photosensor is used. It senses heat and turns on the light when it senses the presence of someone near it. After this, let’s find out-do solar lights need direct sunlight.
Also See: How to Fix Solar Light Sensor
Do Solar Lights Need Direct Sunlight?
How do solar lights turn on at night without any direct sunlight? Yes, direct sunlight is a good and fast way to charge solar light. They need sunlight to hit the panel for the cell to charge adequately which means that they need direct sunlight to work effectively. However, without exposure to direct sunlight also, solar lights can work well due to the presence of photovoltaic cells. The more sunlight that the panels absorb the longer they will stay illuminated at night.
1. Factors Affecting the Sunlight
Sometimes, solar panels do not get direct sunlight due to some reasons like cloudy weather, shadow on the panels, and other seasonal changes. In these situations, direct sunlight does not fall on the solar panels, and they hardly receive passive sunlight and charge the batteries.
2. Effects of Using Solar Lights Without Sunlight
If your solar light is not charged enough through sunlight and works mostly on batteries, they are likely to lose their efficiency and would not last long.
Also See: Does Ring Solar Panel Need Direct Sunlight?
How Much Sunlight Do Solar Lights Need?
Solar panels get charged the most during the peak sun hours and store the most energy. Solar lights need 5-6 hours of sunlight to work properly at night without depending on batteries to provide extra power. But this can differ during the winter or rainy season when the sun hours maybe 5-6, but the intensity of the sun is not as high as in summers. On such days, solar lights may need 6-8 hours to charge. According to the US Department of Energy, there is likely a 30%-50% difference in the performance of solar lights during the off-season.
How Long Do Solar Lights Stay on at Night?
Simply, it depends on a number of factors as well as the efficiency of the solar lights. Therefore, the time for which a solar light stays illuminated at night can depend on the following circumstances. These are some essential points for determining how long do solar lights turn on at night.
1. Type of Solar Panels in the Lights
How long your solar light will illuminate at night depends on the type of solar panel it is connected to. A good solar panel will charge the batteries efficiently, and they can light up for about 15 hours and sometimes even more than that. A good solar panel charges up the batteries well and quickly during the day. A weak solar panel results in quick battery consumption.
2. Power of the Batteries
A powerful set of batteries lets the solar light stay on for longer during the night. Solar lights stay on for a minimum of 10 hours and a max of about 15 hours if the batteries are in good condition. During winter, the time limit can be reduced. This is because during winters the intensity of solar energy is not strong. With this, you have finally learned how long do solar lights stay on at night.
Also Read: How to Use Solar Panel Directly Without Battery?
Why is the Solar Light Not Turning On at Night?
It’s a common issue for solar lights to not turn on during the night. This situation can occur due to a couple of reasons that can easily be fixed.
1. No Power Supply
Solar lights may get power from the sun but still, there is an on/off switch that needs to be turned on by you. Yes, although it is not a daily process but a mandatory one after installing the solar lights. After this, the process is maintained by the photosensors.
2. Blocked Solar Panels
Since solar panels need direct sunlight to charge the batteries, any type of blockage or object casting a shadow over the panels can result in an inadequate supply of sunlight. This influences the charging speed and amount, which in turn results in a solar light that does not turn on at night.
3. Confused Sensors
Sensors of solar lights detect the presence of light and work accordingly. So, if your solar panel is placed at a point where it receives lots of light from other light sources, like streetlights, city lights, etc., there are chances of the sensors getting confused. The sensors consider these lights to be sunlight and turn the bulb off.
4. Wires are Broken
How can solar lights turn on at night with broken wires? It is very possible for the wires to get damaged due to wear and tear from constant exposure to sunlight. Though solar lights are designed to withstand weather conditions, sometimes a loose wire or a broken one can cause the issue. Sometimes animals chew off the wire, and you may not be aware of this.
5. Tab is On
Solar lights have a tab that blocks the flow of the current to the circuit. This can be corrected by pulling the tab to let the current flow and work.
6. Dirty Panels
Solar panels are placed on the roof or other exterior parts where there is enough sunlight. This is essential but on the other hand, this causes dust, debris, snow, rain, etc. to fall on the panels. All these cover the panel, and it does not absorb enough sunlight to charge the batteries. Thus, there is not enough power to turn on the bulbs at night. Clean the panels with a soft cloth and avoid scratching the panel.
7. Batteries are Dead
The extensive use of batteries reduces their capacity to store power. Thus, the energy they store during the day is depleted or exhausted faster. This needs to be fixed by changing the batteries.
8. Water Penetrated
Water from rain or melted snow gets seeped inside the panel sometimes. This damages the coating on the sensors and rusts the metal parts of the light. Therefore, the lights do not work. Get it checked by the technician.
So, how do solar lights turn on at night? The answer to this is in their mechanism and light sensors. Do solar lights need direct sunlight? Well, the answer would be the accuracy of the photovoltaic cells and the intensity of sunlight. How long do solar lights stay on at night? A number of factors affect the time period for this. Looks like we have answered all your questions related to solar lights not working. Now you can self-diagnose the problem with your solar light and get it fixed.
Recommended: How to Make Distilled Water for Inverter Battery?
