At my urban university where students are informed when they are allowed to sit on the lawn and when they are not, it is often difficult to remember nature. However nature, particularly in the form of trees, is never far. From pop culture (Grandmother Willow in Disney’s Pocahontas) to folklore (Johnny Appleseed) trees are deeply embedded in our society.
Trees have become a symbol of nature at large, and an emblem for the green and environmental movements. Not only that, but trees have been of great inspiration for scientists who are looking to nature for solutions to environmental problems. This inspiration can be used to help us bring more sustainable and green technology to the Big Apple itself.
Returning to our Roots
Researchers at SolarBotanic have gone even further than being inspired by trees, they have created artificial trees that, among other things, harness solar, heat and wind energy and filter the air just as trees do. These biomimetic energy sources can be “planted” anywhere from the desert to urban environments and their realistic designs bring nature’s beauty along with nature’s power. SolarBotanic trees utilize nanoleaves that effectively absorb light waves in both the visible and invisible spectrum. This means that the nanoleaves cannot only transform light into energy like other solar cells, but they can also transform infrared rays (in other words, heat) into energy. This way electricity can be provided to a home or a car straight from a “tree” in your front yard.
Nanoleaves are thin, like actual leaves, so they can blow in the wind while remaining attached to the tree. The movement of the leaf flapping back and forth is mechanical energy, which is harnessed by the SolarBotanic tree, providing even more energy and electricity.
Trees do not merely capture light as energy, they also provide us with cleaner air. The SolarBotanic tree does something similar by using a facilitated transport system modeled after our lungs, another inspiration from nature. In the tree there is an “agent” that separates out the CO2, effectively removing it from the air. SolarBotanic is truly paying homage to the tree, and using an already perfect design to provide a beautiful (and effective) form of alternative energy.
Mother Nature Knows Best
Carbon dioxide (CO2) emissions and global warming are an extremely serious issue in the modern world. We need CO2 for everything from oil drilling to blood banks, but too much CO2 in our atmosphere is poisoning our planet at an alarming rate. The government is seriously looking at carbon sequestration, which involves collecting CO2 from the air (mostly from smoke stacks) and injecting it underground, as a method to reduce carbon dioxide levels in the atmosphere.
However, according to the Intergovernmental Panel on Climate Change special report on Carbon Dioxide Capture and Storage, even if the carbon capture and storage (CCS) techniques that are being explored today are 90% efficient, about half of the world’s carbon CO2 emissions will still be released into the environment. Therefore, it is extremely important to find other approaches as well. Dr. Klaus Lackner and Dr. Allen Wright, researchers at Columbia University’s Lenfest Center for Sustainable Energy, have come up with a remarkable, biomimetic alterative—recycling CO2. They have developed a “tree” made of plastic that absorbs CO2, just as trees do, but 1000 times more efficiently. In addition to its efficiency, the plastic resin that absorbs CO2 when it is dry, releases that same CO2 when it is wet. This means that the industries that need CO2 (for oil drilling or carbonated drinks) can purchase recycled CO2. It is also a possibility that recycled CO2 can be converted into gasoline and then the gasoline emissions can be recollected as CO2. This would allow us to still use our cars but ensure that the net level of CO2 in the atmosphere stops rising so drastically.
Dr. Allen Wright, the Senior Staff Associate at the Lenfest Center, pointed out to me that “observing that plants do in fact perform ‘air capture’ did prove at the outset that it was possible” however he also says that the “pine branch shape” of the resin is “purely coincidence.” As he says, “A pine branch shape worked well for that because the ‘needles’ would compress nicely. It is not a particularly useful geometry for many reasons. The term ‘artificial tree’ is use to help people understand what we are doing. A practical device deployed in the field for air capture will not likely look like anything found in nature...more perhaps like a carousel sitting on top of a shipping container.”
Recycling carbon is exactly how nature works. CO2 is produced as a byproduct but it is recycled throughout nature (through the carbon cycle). This technology takes nature’s foolproof method or “recycling” carbon dioxide and applies it to the excess CO2 in our atmosphere. As Dr. Wright explained to me, “the goal of air capture is to remove roughly 10-30% of the CO2 in the air passing through the collector, not to produce CO2 free air. That would put the air exiting collector at a pre-industrial level of CO2.” Therefore plants can still grow and participate in the carbon cycle without being affected by the CO2 emissions people are producing.
This video elaborates on how this plastic “tree” could dramatically change our world.
With sustainable technology like this we can continue to live our city lives while still changing how we interact with the environment.
Biomimicry in the City
New York is a large city with the majority of its greenery confined to parks. Yet the city is making an effort to incorporate green energy and biomimicry into its urban ways and Clean Energy Connections is making an effort to help provide the network to make this transformation possible. On November 3rd, there will be a fascinating panel called Biomimicry in the Big City: Can Nature Inspire Cleantech Solutions?
It is not always easy to remember the trees when you are surrounded by the bright lights and steel of New York City (or any urban environment). But the innovations and inspiration trees provide us can keep our cities—and our world—cleaner, more energy efficient and more sustainable.