How To Charge Solar Lights Without Sun

In this guide, we discuss how to charge solar lights without sun.

Of course it’s best to charge with direct sunlight, but indirect sunlight also works and we will list some tips for you in this guide. Some are more effective and faster than others.

Let’s check them out

Indirect Sunlight

Use Mirrors to Redirect Sunlight

Using a mirror will help to reflects the sunlight onto the panels to receive as much sunlight as needed.

When doing this method the size of the mirror matters, so you need a big mirror to make this happen.

Use Artificial Lighting Bulb to Charge Solar Lights

The light rays from the incandescent bulb can charge a solar light efficiently. Incandescent light bulbs projects off light waves similar enough to sun’s ultraviolet waves that the solar cells can collect and convert into electrical energy.

The closer the solar light to the bulb, the less time it will take your solar panel to charge. The only exception is that the light must be strong enough (40 – 100 W bulb) to provide charging capability, but it will not be as nearly efficient as direct sunlight.

This works for smaller solar devices such as battery bank. Just put photovoltaic cells facing the light under a lamp about 20″ away for a few hours and return.

Use LED Lights to Charge a Solar Light

Another smart tip to charge solar light is by using LED lights. LED flashlights can charge solar lights when you don’t have access to indoor lighting. You need to charge your solar panel for about 10 to 12 hours while using LED light.

LED light creates visible, long infrared and ultraviolet waves similar to the sun, but not as strong as the sun. 

Clean Your Solar Panel Surfaces

Above all else, cleaning your solar panel’s surface is important to maintain the highest solar cell efficiency. A dirty solar panel surface degrade the performance and regularly clean them makes a huge difference especially for home and RV use.

Learn More: Solar panel maintenance guide

Charge Via Standard Power Outlet

Many great solar powered products have built in charging capability via wall socket and USB port. They are the fastest way to get a full charge right away without any interruption.

It’s versatile and works in any situation.

Common FAQ

How To Charge Solar Devices On Cloudy Days?

Even during cloudy days, the solar panel can still collect energy, but it will not be as strong as a bright sunny day. The best way to charge a solar device under a cloudy day is the use of an amorphous solar panel over polycrystalline or monocrystalline panel.

In layman’s term, amorphous panel isn’t as efficient as mono and polycrystalline cells, but it gathers more light energy.

To learn their differences in depth, check out amorphous vs crystalline breakdown guide

How To Charge Solar Devices During Cloudy & Cold Winter?

Just like a cloudy day, solar panel can still collect solar energy during a cold and cloudy winter day. Sun’s ultraviolet rays will penetrate the clouds and hit the solar panel’s surfaces even during snow and heavy cloud coverage.

If you get snow on your rooftop solar panels, then you have to clean them off and reposition them to maximize solar efficiency.

However, it’s not as fast or efficient compared to a hot summer day with long peak sun hours.

Can Solar Lights Be Charged Indoor?

There are various ways solar lights can be charged indoor via:

  • Artificial lights
  • LED
  • Windows
  • Standard grid power

Ying Xu

Graduated from the University of Kansas with an Aerospace Engineering degree & served 4 years as an US Air Force officer. Experienced with basic survival skills, weapon system security,  technical disaster recovery, and system troubleshooting

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