Solar lights are becoming increasingly popular for decorating patios, lining driveways, and illuminating properties. They require little to no maintenance and can contribute to significant savings on your annual electricity costs.
If you’re thinking of installing a solar lighting system on your property, you’ve probably wondered, do solar lights need direct sunlight? This article looks at how solar lights are powered and discusses different ways to maximize efficiency. Some of the topics we cover include:
- Whether or not solar lights need sunlight
- If solar lights charge in the shade
- How solar lights work
- Different ways of charging solar lights
- Choosing the right solar lights
Do Solar Lights Need Direct Sunlight?
Most solar lights don’t need direct sunlight to function.
While solar lights work more effectively and charge quicker with direct sunlight, they can function well without it. However, all solar lights need some light source, such as an LED or incandescent bulb.
Solar lights are extremely convenient as they can be easily powered. They are environmentally friendly and cost-effective. Although they typically require a significant up-front cost, solar lighting can contribute to long-term savings. Solar technology is also becoming more affordable every year.
Solar energy is virtually inexhaustible. As long as you keep your solar equipment in good condition, your solar lights can last many years. What’s more, solar lighting systems are easy to maintain.
The most important aspect of solar lighting maintenance is cleaning. As long as they are kept clean and free of stains, smudges, and debris, they can function optimally. It’s important to keep an eye on the condition of the lights and to monitor electricity bills to spot potential issues.
Do Solar Lights Charge On Cloudy Days?
While solar lights charge most effectively with direct sunlight, they also charge on cloudy days.
Essentially, solar lights charge from a variety of light sources, including daylight and artificial sources. Although clouds diffuse rays of light, they don’t block them completely, ensuring the solar lights can charge. The less atmosphere that rays must pass through, the faster and more efficiently your lights will charge.
In general, thick, dark clouds absorb the most light. These are more likely to reduce the efficiency and output of solar equipment than finer, white clouds. However, clouds won’t stop your solar lights from charging.
Do Solar Lights Work In The Shade?
As long as there is some light source, solar lights work in the shade.
The same principle applies to solar lights in the shade as with the clouds. As long as the light is picked up by the sensor on the device, it can generate energy. In the total absence of light, the lights are unable to produce electricity.
Do Solar Lights Work Under Trees?
Again, as long as light passes through the solar sensors, solar lights work under trees.
While trees generally create shade from direct sunlight, they typically let some light through. Positioning solar lights beneath trees isn’t optimal, but it shouldn’t stop them from working.
How Much Direct Sunlight Do Solar Lights Need?
Depending on the type, size, and output of the lights, the amount of sunlight needed to charge and power solar lights can vary.
It is typically proportionate to the amount of light exposure. For example, a solar light system is likely to charge faster and run for longer if it experiences several hours of uninterrupted sunlight exposure.
Solar light manufacturers claim that their products will provide a certain length of charge per hour of direct sunlight exposure.
For high-quality lighting systems, you can expect manufacturers to estimate somewhere between 12 and 15 hours of charge per 8 hours of exposure to direct sunlight.
It may not be practical to position your lights where they get 8 hours of uninterrupted sunlight regularly. Therefore, solar lights may not perform to their maximum capacity all the time.
How Can Solar Lights Work Without Sun?
To understand how solar lights work without the sun, you must first have a general understanding of how solar lighting systems work.
Solar lights work due to the photovoltaic effect. The solar cell within a solar light is the most important component. It is the module that converts light into direct electrical current (DC).
The solar cell is easy to identify. It is a dark panel, usually positioned at the top of the unit. It is generally made up of several layers of crystalline silicon and various other chemicals. Once light passes through the cell, an electrical transfer occurs, sending DC through the embedded wires into a battery.
As the light dissipates in the evening, the solar cell eventually stops converting the light to energy. However, the stored electricity remains in the battery until it is needed. When there is no sun, solar lights use the stored energy for power. So, essentially, the battery provides electricity to run the lights at night or in the absence of light.
When the electricity runs out, this process must be repeated.
Solar lights have photoreceptors that detect sunlight. When sunlight is identified, the system shuts off the light, and the conversion process begins again.
During winter or times where there is not a lot of light during the day, solar lights may not be able to generate enough electricity to run the lights for an entire night. However, in summer, when the nights are short and daylight is at a maximum, solar lights have sufficient charge to run throughout the whole night.
How To Charge Solar Lights Without Sun?
A key advantage to solar lighting is that it can be charged without the sun.
While it’s important to note that direct sunlight with strong UV rays is best for charging solar lights, you can use alternative light sources.
The most straightforward approach is to use a standard incandescent lightbulb. This is most effective when charging small lights, such as a solar flashlight. Incandescent lights produce light waves that solar cells can process and convert to energy. However, the incandescent lightbulbs must be bright enough so the light wavelengths are similar to the UV rays produced by the sun.
While you can charge your solar lights with incandescent bulbs, they are not as efficient as sunlight. Incandescent lights need the power to function. Unless you are using solar energy to power your incandescents, charging solar lights in this way isn’t a renewable approach.
Charging solar cells with incandescent bulbs will also take longer than sunlight as the light isn’t as powerful.
To charge, position the solar cell approximately 20 inches from the incandescent bulb. The higher the wattage of the bulb, the faster it will charge the light.
LED and halogen lights are also suitable for charging solar lighting systems. Again, these lights are unlikely to charge your device as quickly as natural light.
Can You Charge Solar Lights With A Flashlight?
In theory, you can charge solar lights with a flashlight.
Like with lightbulbs, the brighter the flashlight, the faster it can charge your solar system. Most lamps and flashlights have an output of around 50 to 100 lumens.
To give this some context, it takes approximately 300 to 500 lumens to provide adequate lighting for your living room. On a cloudy day, outdoor light can be as little as 1,500 lumens.
On a bright, sunny day, you may experience 100,000 lumens from the sun.
As you might expect, flashlights are nowhere near as effective at charging a solar cell as natural light. In fact, it is around 0.1% as powerful as consistent light exposure on a sunny day.
Should You Bring Solar Lights In During Winter?
While mini solar lights are generally durable enough to last the winter outdoors, many people choose to bring in their decorative lights during the dark, cooler periods.
As we’ve discussed, solar lights are far less effective in winter. The risk of damage due to wind, ice, snow, and rain may outweigh their usefulness. If your solar lights have large glass parts, perhaps they are better off in storage during winter.
However, if you want to maximize the lifespan of your lights, it’s recommended that you expose them to the sun once per month, even while they’re in storage. Batteries last longer if they can maintain a charge. Although taking your solar lights out of storage once per month takes extra effort, it helps ensure they run more efficiently for longer.
The reason for taking your solar lights in during winter is to protect them so be sure to keep them in a suitable place. Metals and electrical components are susceptible to water damage, meaning you should always store your lights in a cool, dry environment. A well-insulated attic is often the place to store solar lights in winter.
Choosing The Right Solar Lights
Choosing the right solar lights depends on your needs, budget, and environment.
In general, high-quality lights with strong solar cells are the brightest and most efficient. However, they are also the most expensive. While premium solar equipment is often worthwhile in sunny regions, it may not hold as much value in areas that lack sunlight.
If your property experiences plenty of sunshine, choose whatever lights take your fancy.
Now, let’s take a look at some options for less sunny areas.
Outdoor Solar Lights For Shaded Areas
Some of the most effective solar lights for shaded areas include:
- Fairy lights
- Security lights
- Motion lights
Even dimmed fairy lights can give off a pleasant aesthetic. Security and motion lights can store charge, making them useful in all scenarios.
Outdoor Solar Lights That Work In Winter
During winter, you’ll need lights that can stand up to the elements.
Pathway lights, lanterns, and spotlights can be positioned to absorb as much light as possible during the day. While pathway lights may not stay lit the entire night, you should get several hours of illumination.
Spotlights and lanterns can be controlled remotely, allowing you to preserve the charge and use the light only when necessary.
Hybrid lighting is also useful during winter. These systems use solar and artificial light for power through fiber optic cables.
Sources
https://www.axionpower.com/knowledge/charge-solar-without-sun/
https://ecavo.com/charge-solar-without-sun/
https://www.istorage.com/blog/how-to-store-outdoor-solar-lights-for-the-winter/
