How Do Solar Lights Work?

Solar lights: How do they work?

There are two main ways solar lights are powered:

Active solar lighting

Active solar lighting is the most common way solar lights are powered. This type of solar light is generated by capturing and converting sunlight into energy. Active solar lights utilize a battery to store energy that’s collected from sunlight during the day. At night, the battery operates the light for as long as there is energy stored to power it.

Passive solar lighting

Passive solar lighting refers to lighting that doesn’t require equipment to convert the sun’s light into energy. For example, a sunroom takes advantage of passive solar lighting to keep a room bright during the day. You can also passively light your home through a skylight.

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How to choose solar lights

Jeff Brandlin, owner of Assurance Electrical Services, an electrical services company specializing in solar installations in Arizona, advises consumers to ask themselves a few questions before they go shopping for solar lights.

“Think about what your purpose is for using solar lights,” Brandlin said. “Are you looking to use them for general lighting around your home? Or are you looking to use them for specific tasks, like accent lighting or security lighting? [...] Once you know what your purpose is, you can start to compare different types of solar lights.”

Types of solar lights

As solar lights have become more commonplace and homeowner interest increases, companies are responding to consumer demand by offering attractive and affordable options for every design, style and budget.

There are many types of solar lights available for both residential and commercial applications.

Residential outdoor solar lights

Outdoor solar lights use the same technology as solar panels but on a much smaller scale. For example, if you open up an individual garden pathway light, you’ll see that each has a tiny solar array and battery embedded.

Residential outdoor solar lights are easy to install and come in a variety of styles, such as garden stakes, lampposts, lanterns and string lights. You can also find solar emergency lights and camping lights too.

Commercial outdoor solar lights

Lighting manufacturers are starting to offer solar lighting options for commercial use, including:

• Solar street lights
• Solar sign lights
• Solar traffic lights
• Solar parking lot lights

Indoor solar lights

The technology exists for indoor solar lights, but they’re a bit more expensive to purchase and install because you need to install a photovoltaic (PV) panel (or two) on your roof to power them. If you already have a solar array on your roof or are thinking about installing one, your vendor can work with you to include lighting solutions.

Some homeowners who don’t already have a solar array but want to use solar lighting in a specific area, such as to light up a garage or shed, may install just a few panels to power the lights.

Other solar lights

Some manufacturers are starting to offer individual solar light fixtures, such as desk lamps that operate on energy from the sun. These fixtures need to be placed and operated near a window to work effectively.

Benefits of solar lights

There are many benefits of solar lights, from the ease of use for homeowners to the increased green credentials for commercial builders and landlords. Solar lights also cut down on energy costs for both residential and commercial properties.

David, a ConsumerAffairs reviewer from Florida, is a property investor who has realized the value of solar lighting.

“We have a lot of properties,” David said. “And we just thought, ‘Let’s give solar a try.’ We have a lot of solar lights on our own house too.”

Depending on the way you use solar lights, you may appreciate some or all of these benefits:

• Energy savings: There are no electrical bills associated with solar lighting systems, so your power bill will decrease.
• Easy to use: It doesn’t always take an electrician to install solar lights.
• Environmentally friendly: Many homeowners like solar lighting because it’s a sustainable solution.
• Affordable: While powering a whole house using solar energy can be expensive upfront, using outdoor solar lighting is a green solution that’s within reach for most homeowners.
• Stylish: As demand for solar lighting grows, manufacturers are offering many styles for both home and commercial use.
• No wiring or trenching: Traditional outdoor lighting requires expensive wiring and trenching. Solar lights don’t require this because the technology is self-contained.
• Helps with green credentials: For businesses striving to achieve green business certification, installing solar lights can help.

Drawbacks of solar lights

There are a few drawbacks to be aware of before purchasing and installing solar lights:

• Operating time varies: Depending on how much sun is available to charge your lights, you might get 10 hours of run time one night and half that amount of time the next. That’s because operating times depend on sunlight exposure during the day.
• Specific sun requirements: Outdoor solar lights require good direct sunlight. If your home or layout doesn’t allow for that, you can hire a professional to run wiring to roof panels, but this will increase the overall cost.
• Replacement parts: Not all makes and models of outdoor solar lights offer replacement batteries and bulbs. This means you might have to replace a whole fixture at the full purchase price. Be sure to check for this when you’re comparing brands and options.
• More expensive: Solar lights are often more expensive than standard lights, but they eventually pay for themselves. This is especially true if you live somewhere with solar incentives.

Bottom line

Solar lights are becoming more common, especially for outdoor uses like lighting a garden or walking path. And more municipalities and corporations are starting to use solar energy to power lighting in order to avoid expensive wiring and trenching.

But the upfront cost can be a deterrent, especially if you’re unsure about eligibility for local or state solar incentives. Before investing in solar lighting, understand your options as far as products, costs and incentives. This will help you decide if investing in solar lights makes sense for you.

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