These trees do more than just add ambiance. Harnessing the wind to generate electrical energy usually brings to mind thoughts of huge land- or ocean-based wind farms consisting of huge towers with two or three blades, each more than 100-feet long, on the top. The size, weight, noise, and vibration of industrial wind turbines restrict their use to large open spaces. Newwind, a French startup, has developed a much smaller, urban-space-friendly “Wind Tree,” reports Electrek.
The Wind Tree, which produces sufficient energy to power small buildings or streetlights, is designed to connect to a nearby energy storage system. The trees are each about 30 feet tall and 26 feet in diameter, and weigh approximately 5,500 pounds. Each tree has 54 Aeroleafs mounted vertically on tree branches. The Aeroleafs are 3.2 feet high and, spinning at optimum speed, are capable of generating 65 watts each. So, a tree with 54 leaves has an energy-generation capacity maximum of 3,510 watts (3.5kW), about the same as a small home solar installation.
The Wind Tree isn’t intended for residential applications or city streets, as it needs a good deal of space. The closest building must be at least 32 feet away and the tree needs to be installed within 164 feet of an electrical panel to which it attaches. The prime application, according to the company, is for civil engineering and city landscaping projects.
The tree’s leaves are held in place with a magnet assembly and can generate energy at speeds as low as 4.5 mph, without distracting sound. According to Newwind, “Current is generated by a (rotor) magnet assembly, which is rotated by a blade moving across circuit (stator). Micro-electricity generation is created with and multiple turbines combine to capture the lowest winds and accumulate their power.”
The trees are made of steel and the leaves of lightweight plastic that is “treated with a resin which protects it from weather conditions such as humidity and salt” according to IFL Science.
Electrek reported that Newwind has “planted” more than 40 wind trees in France and is now exploring market possibilities in the U.S. The trees currently cost $67,500 each before delivery and installation, which again rules them out for most residential applications, even if you have the required space.
It’s interesting to see developing technologies that could work alone or in conjunction with solar installations to produce energy without using fossil fuels.