What is a solar tree?

Typically used for commercial applications rather than residential properties, solar trees don’t produce as much electricity as rooftop solar arrays, but they do decorate urban spaces and increase public awareness about the beauty of solar energy.

Solar trees have “leaves” made up of solar panels. It’s unlikely anyone would mistake a solar tree for the real thing — they’re more artistic and sculptural than natural, but many find them more aesthetically pleasing than other arrays.

Key insights

• Solar trees are as much a form of art as they are a source of electricity.
• Solar trees are typically seen on commercial properties rather than residential properties.
• Currently, their cost makes solar trees an unrealistic investment for homeowners.
• Some solar tree designs have rotating panels, which can help collect more sun throughout the day.

How does a solar tree work?

Like standard solar panels, solar trees convert sunlight into electricity that can be used to provide power.

"The photovoltaic 'leaves' of the solar tree capture sunlight and convert it to power, which is then sent down the structure's trunklike central pillar to an internal battery," said Jay White, chief scientist of Aquion Energy, a manufacturer of batteries and battery systems for solar energy storage. "Many designs have rotating panels that can move throughout the day to gather sunlight."

As the sun moves across the sky, solar trees move in lockstep with the sun to maximize exposure. This is different from standard solar arrays, which are usually fixed to the surface of a rooftop or affixed to the ground and are not capable of following the sun as it moves from east to west.

The internal battery in the solar tree can store electricity that can be used to power specific applications like outdoor lights or car charging stations, or to supplement electricity provided by a standard solar array.

» MORE: How do solar panels work?

What are the benefits of solar tree design?

According to White, with Aquion Energy, while solar trees "have a limited power generation potential," their other benefits set them apart from typical solar panels. The goal of many solar trees is to "create public awareness of renewable energy by encouraging people to observe and interact with solar in innovative ways."

They "provide vitality as well as shade while taking up very little space," White said. "These trees could be used in a variety of ways by a creative mind: shade for city sidewalks, parking lots and playgrounds, among other things."

Solar trees have the following benefits:

• Generating electricity: Solar trees generate electricity that can be used to supplement the electricity production of a larger solar array.
• Providing artistic beauty and whimsy: Solar trees are striking in appearance, defined by sleek lines and featuring unusually shaped solar panels arranged in a unique configuration. Their size is comparable to an actual tree. This gives solar trees a whimsical look that draws attention and beautifies the surrounding landscape.
• Taking advantage of vertical space: A solar tree occupies space in the air, not on the ground. This makes solar trees an excellent fixture in parks and on lawns.
• Giving shade: In densely populated urban spaces, especially in warmer climates, solar trees provide welcome shade as well as electricity.

Are there any downsides to a solar tree?

When you’re considering the downsides of solar trees, it's important to remember this is relatively new technology that is changing and improving over time. As the technology matures, some of these problems may be solved with improvements.

Some of the downsides of solar trees include:

Are solar trees expensive?

Solar trees are generally acknowledged to be very costly for the amount of power generated. This is why most solar trees are not found on residential properties and are more commonly commissioned by commercial customers. The trees are less a significant source of electricity than a visual symbol of a business’s commitment to solar energy.

• Moving parts: While a standard rooftop solar array has no moving parts that can break, many solar trees have moving parts that may require maintenance over time.
• Cost: A solar tree can cost as much as $100,000, which puts these systems out of reach for most residential customers.
• Output: According to White, the chief scientist at Aquion Energy, typical solar trees may generate between 1.7 and 16.5 kilowatts of power. However, a typical commercial rooftop solar array can generate 200 kW, according to a report from the National Renewable Energy Laboratory.

Solar tree vs. solar panels

Aesthetics has never been a hallmark of the rooftop solar panel array. Roof-mounted panels tend to be valued for their utility rather than their looks (though some solar energy system owners, like a reviewer from California on our site, do appreciate some solar companies’ panels for their “low-profile” appearance).

Solar trees are less efficient than most rooftop arrays at producing electricity, but many homeowners find them beautiful or, at the very least, visually interesting, and they call attention to the benefits of solar power. Solar trees can also easily be erected in densely populated areas because they're built up, not out — and they can deliver power to out-of-the-way spaces in parks and open green areas.

» MORE: Solar shingles vs. solar panels