Solar trees in Super Tree Grove at Gardens by the Bay, Singapore. Coleen Rivas / Unsplash
Did you know that the shape of airplane wings were designed to mimic the sloped wing tips of eagles? That the ridges on whales’ fins that create an aerodynamic flow in water inspired the shape of the modern wind turbine? That termites drilling holes in their mounds to cool down in the desert summers influenced a method for designing more energy-efficient buildings?
Biomimicry has long been one of my favorite growing areas of science and sustainability — emulating models, systems or elements of nature to solve complex human problems. After all, mother nature has been around a lot longer than humans; she has a lot to teach us. So, as a specialist focused on solar energy, I’ve often wondered what nature can teach us about how to capture our power from the sun. Enter solar trees.
What Are Solar Trees?
A solar tree is a device resembling a tree in shape, but with photovoltaic (PV) panels in place of its crown. The “leaves” of the tree capture solar energy and convert it to electricity, with branches funneling that electricity down through a trunk and into a central battery within. In essence, they provide the same benefits as solar panels, but they use only a fraction of the surface area necessary for an array of solar panels.
Solar trees are not a new invention, but they’re enjoying a rising popularity. Most of our readers may recognize the most iconic solar trees in Singapore’s stunning Gardens By the Bay, as seen in productions like Crazy Rich Asians and The Bachelor.
As they exist today, more solar trees raise public awareness around sustainability than are used to generate residential or commercial power. What’s more, the trees are still perceived as “futuristic,” but it might be time we start shifting our mindset about these inventions by incorporating them into our vision of what sustainability looks like in practice. Here’s why:
Benefits of Solar Trees
At first glance, solar trees might seem impractical — more art than function when compared to the best solar panels. But solar trees offer a few surprising benefits over their ground-mounted counterparts, including:
- Solar trees preserve land: Since solar trees are vertically integrated, they require significantly less land than solar farms. The same logic would apply to a high-rise being able to fit more residents than a one-story house. Plus, because of their greater heights, the panels may receive more sunlight than a ground-mounted or roof-mounted arrangement would.
- They can provide habitat for rare flora and fauna: Solar trees like those in Singapore’s Gardens By the Bay are large enough to host tropical flowers, vines and plants on its trunk and branches. These valuable habitats provide homes for plants and animals, protecting biodiversity in urban areas.
- Solar trees require little maintenance: Besides cleaning debris off the solar panels every now and then, solar trees are standalone electrical units requiring little to no maintenance.
- The trees cool heat islands: By creating shade in urban environments, solar trees reduce the amount of thermal energy that is reflected off of urban surfaces like asphalt, concrete and brick. This can combat the most deadly effects of climate change within cities.
- They increase awareness of clean energy: The striking structures are immediate attention-getters, conveying a message of creativity, resourcefulness, humility and the need to incorporate sustainability into everyday life. We see similar art installations at work across the world, such as the Terra pavilion in Dubai.
Solar Trees Vs. Solar Panels
We mentioned that solar trees serve essentially the same purpose as solar panels but require a much smaller footprint to do so. But are there any other significant differences outside the trees’ widespread adoption? Let’s dig in.
Solar panel efficiency is a measure of how much energy is produced relative to the amount of sunlight that strikes the panels. So, to compare a standard solar array and solar trees in terms of efficiency, we’d need to know the specs of the solar cells used within the tree.
However, when it comes to space efficiency, trees take the crown. This solar tree in West Bengal, India produces enough energy to power five homes in the U.S. Solar trees in Lynn Haven, Florida are capable of powering six to seven homes. Instead of using an entire roof to produce this electricity, the trees do so using only a few square feet of ground space.
Since solar trees are still rare in the U.S., the average installation cost is high. According to top solar tree company Spotlight Solar advertises total pricing to be $40,000 to $80,000. Based on current average solar costs, you could buy a 15-kW to 30-kW solar panel system (for context, the average home needs a system between 5 kW and 10 kW).
Of course, the complexity and size of the solar tree will influence the final price. Until solar trees reach the commercial mainstream, demand will limit their widespread availability.
Storage and Distribution
Solar trees are used to produce electricity that will be used onsite. Storing and distributing the energy generated by the trees (like solar farms and power plants do) would require larger solar batteries and complex systems of transmission.
While solar panels are used primarily on rooftops or mounted on the ground, solar trees offer a different type of utility. In addition to energy, they provide shade and whimsy while taking up minimal surface area. A creative mind could find endless uses for these trees: shade for city sidewalks, parking lots, playgrounds, backyards and more. This brings us to…
The Future of Solar Trees
The metallic, modern look of solar trees might turn off the average reader, but keep in mind that as the technology improves, investment flows and demand increases, they’ll become much more similar in appearance to real trees or other plants. This modern mimicry will allow us to blend the trees into our forests, yards, coastlines, parks and cities.
Apart from residential applications, here are a few of our favorite ideas for the uses of solar trees:
- Shade along highways or agricultural areas
- Artistic installations in public parks, outdoor malls and gardens
- Energy sources for carports and parking lots
Solar trees may still be a few years from the mainstream, but relative to other solar panel alternatives like solar roads, they offer a lot more practical value. The efficiency and versatility of the trees make them ideal for cities and densely populated areas, making us think they will be commonplace sooner than you might expect.
Looking to “Plant” a Solar Tree?
The options are still somewhat limited, but there are a number of organizations that can install solar trees throughout the U.S. We’d recommend starting with these companies:
Smartflower offers stunning designs of solar devices in the shapes of trees and sunflowers, with solar petals tracking, opening and closing with the sun for optimal energy conversion. We’re talking about premiere trees here. Each tree has an output of 2.5 kW at peak power, which is about half the power production of a small home rooftop solar system.
North Carolina-based Spotlight Solar produces models of several different types of solar trees. With flexible configurations, accessory options, efficient panels and quick assembly, Spotlight Solar’s trees serve as great options for public parks, carports and walkways.
Founded in 2006, Beam Global (formerly Envision Solar) produces patented infrastructure products for the electrification of transportation. The San Diego-based company offers solar trees and solar carports as electric vehicle charging stations.
Karsten Neumeister is a solar energy specialist with a background in writing and the humanities. Before joining EcoWatch, Karsten worked in the renewable energy sector of New Orleans, focusing on solar energy policy and technology. A lover of music and the outdoors, Karsten might be found rock climbing, canoeing or writing songs when away from the workplace