Bold ideas that solve the world’s energy needs.
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Best In Snow
by Stuart Wolpert
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Anyone who’s experienced winter does not normally think of cold weather as being an opportunity for energy-generation. It’s typically seen as the opposite – heating bills increase, solar panels are covered in a blanket of white, and phone batteries quickly drain in sub-zero temperatures. But what if the snowfall that comes with winter had a hidden benefit, by providing the very electricity that we consume? A new device, called a snow-based triboelectric nanogenerator, or snow TENG, is designed to create electricity from falling snow. By providing its own power, it does not need batteries, making it convenient for use in remote areas. It also opens up the potential for a new wave of wearable electronics, more efficient solar panels, and even entire buildings that can produce energy during winter weather with a simple coat of paint.
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How does it work?
Since the 1960s, scientists have understood a strange phenomenon of snow: It’s positively charged. That means if it lands on something with a negative charge, it will pass over its electrons, creating static electricity. “Static electricity occurs from the interaction of one material that captures electrons and another that gives up electrons,” says Richard Kaner, a professor of chemistry and biochemistry at UCLA. “You separate the charges and create electricity out of essentially nothing.” “Snow is already charged, so we thought, why not bring another material with the opposite charge and extract the charge to create electricity?” says Maher El-Kady, a UCLA assistant researcher of chemistry and biochemistry.
Since the 1960s, scientists have understood a strange phenomenon of snow: It’s positively charged. That means if it lands on something with a negative charge, it will pass over its electrons, creating static electricity. “Static electricity occurs from the interaction of one material that captures electrons and another that gives up electrons,” says Richard Kaner, a professor of chemistry and biochemistry at UCLA. “You separate the charges and create electricity out of essentially nothing.” “Snow is already charged, so we thought, why not bring another material with the opposite charge and extract the charge to create electricity?” says Maher El-Kady, a UCLA assistant researcher of chemistry and biochemistry.
The performance of the device depends on the efficiency of the other material at extracting these electrons. After testing a large number of materials including aluminum foils and Teflon, researchers found that silicone and its negatively-charged surface produced more charge than any other material. Silicone – a synthetic rubber-like material that is composed of silicon atoms and oxygen atoms, combined with carbon, hydrogen and other elements – is widely used in industry, in products such as lubricants, electrical wire insulation and biomedical implants. The design of the device, which has a layer of silicone and an electrode to capture the charge, can be produced using a 3-D printer.
Future Applications
Future Applications
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“As a starting point, I think wearables for tracking purposes could be the most practical application,” says El-Kady, given that Snow TENG still only creates slight levels of energy. The team has already tested putting their snow TENG onto the bottom of hiking boots and bike tires. As the generator rolls through snow, it captures energy.
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“Snow is already charged, so we thought, why not
bring another material with the opposite charge and extract the charge to create electricity?” |
The snow TENG is also similar to a weather station, able to tell you how much snow is falling, the direction the snow is falling, and the direction and speed of the wind. It can send signals indicating whether a person is walking, running, jumping or marching – opening up additional applications; for instance, using it to monitor winter sports, such as skiing, and for identifying the main movement patterns used in cross-country skiing, which cannot be detected with a smart watch. It could usher in a new generation of self-powered wearable devices for tracking athletes and their performances. Because its source materials are so inexpensive, El-Kady tells us that he thinks each small sensor could be built for all of $1. If you wanted to add in a Bluetooth chip to transmit wireless data, that may add on another buck or two.
Longer term, El-Kady imagines all sorts of other possibilities. About 30 percent of the Earth’s surface is covered by snow each winter, during which time solar panels often fail to operate. The accumulation of snow reduces the amount of sunlight that reaches the solar array, limiting the panels’ power output and rendering them less effective. The new device could be integrated into solar panels to provide a continuous power supply when it snows. It could also be painted onto buildings (just as silicone paints are now), to provide some level of waterproofing and resistance from humidity. And of course, when it snowed, the building would basically be one giant frozen energy factory.
Of course, Snow TENG doesn’t do much for the southern hemisphere – ninety-eight percent of snowfall happens up north. But as the world faces a future filled with more extreme weather and an unending thirst for energy, we won’t just need one technology to get by – and we’ll need to adapt to all elements.
Longer term, El-Kady imagines all sorts of other possibilities. About 30 percent of the Earth’s surface is covered by snow each winter, during which time solar panels often fail to operate. The accumulation of snow reduces the amount of sunlight that reaches the solar array, limiting the panels’ power output and rendering them less effective. The new device could be integrated into solar panels to provide a continuous power supply when it snows. It could also be painted onto buildings (just as silicone paints are now), to provide some level of waterproofing and resistance from humidity. And of course, when it snowed, the building would basically be one giant frozen energy factory.
Of course, Snow TENG doesn’t do much for the southern hemisphere – ninety-eight percent of snowfall happens up north. But as the world faces a future filled with more extreme weather and an unending thirst for energy, we won’t just need one technology to get by – and we’ll need to adapt to all elements.
