A BREATH OF FRESH AIR...Follow article
Energy harvested from wind power is at the forefront of the minds of the engineers involved in the creation of new devices that can harvest renewable energy in an effort to reduce our dependency on more traditional sources of power generation that produce masses of pollutants.
NewWind, based in France, is installing tree-shaped wind turbines, called WindTree, in Paris and other towns and also European cities, to help address the Worlds growing power needs and the desire for that power to be as clean as possible.
These unique wind trees consist of a steel trunk and branches spanning 10x8 metres, with 63 ‘leafs’ positioned around the limbs. These leafs, or Aeroleafs as they are known, silently rotate about their own axis in the slightest of breezes with a power output said to be around 2400 kWh annually at peak efficiency. Silent and aesthetic, these trees are almost like sculptures and certainly many people would find them pleasing to the eye, especially when compared to the more numerous wind farms with their massive turbines and associated noise. Obviously, the power generation figures when compared to the latter are hugely different, but the purpose of the wind trees is to harness wind power and generate electricity in areas where currently there is nothing doing so and to do so in a way that isn’t industrial in appearance or physically overpowering.
Supplying the power
According to the information available from NewWind, they claim one WindTree can supply 15, 50W street lamps, 83% of the typical consumption of an average European household (excluding heating) per year. Other claims include that a single WindTree can provide power for 100 square foot, low power office or can be used to filter a 1,766 cubic feet pool for a year or power an electric car for 10,168 miles per year (a rather precise figure I thought). These figures are comparable to a quoted 164 gallons of fuel to produce the same output in kWh, and a reduction in Co2 to the tune of 3.2 tonnes annually when compared to an oil-fired power station.
Natural subtlety is certainly a prime consideration in its design, but also its ingenuity, capturing those faint breezes that do little more than stirring the leaves of a tree. Which, oddly enough was the inspiration for the design of the WindTree itself, according to the company’s founder, Jérôme Michaud-Larivière, who arrived with the idea while in a Paris park, when he “saw the leaves tremble when there was not a breath of air.”
Designed for industrial areas, around a factory building or in and around urban centres, exploiting those small air currents flowing alongside buildings and streets. The energy production of the trees, which currently cost £23-£24k, is obviously not as great as the more conventional wind turbines you see dotting the countryside, but at an average wind speed of 7.8mph, they could potentially be profitable within a year at that current cost. The WindTree can produce electricity in wind speeds as low as 4.5 mph, due to the low friction operational design of the Aeroleaf, with a lifespan estimated to be around 25 years, financial return certainly seems possible.
Improving the design
NewWind intends to keep on developing and researching improvements to its design and other potential uses for the WindTree and its leafs, for instance, the Aeroleaf doesn’t need to be mounted on the Wind Tree to function, they could easily be placed on a building in groups, to create what would look like a living wall of power generation as the Aeroleafs spin independently. Research is currently underway to improve its appearance, reduce its production costs and make it more durable. Jérôme is already imagining a wooden trunk to replace the steel one with natural fibres utilised to construct the leaf blades.
Jérôme Michaud-Larivière and his design.
Will the Wind Tree be a success? It may still be, at the time of writing, the company NewWind went into judicial liquidation, which is sad, but there is still hope as the company is seeking a buyer, so, maybe! It would be interesting to establish how ‘green’ the manufacture of this energy gathering device is and offset that with the lifespan and energy gathering potential it can offer to establish its environmental impact. If the WindTree manufacture isn’t environmentally detrimental and the power generation possibilities are adequate, or better, then it will prove to be another fantastic addition to the arsenal of weapons we can use to help us create a cleaner more energy efficient world, if a buyer can be found! It's not over just yet so it seems.