July 5, 2007 The problem of keeping your mobile phone fully charged when miles away from a conventional electricity source is being tackled by UK wind turbine specialists, Gotwind. The Orange wind charger prototype is a small, portable tent mounting mobile phone charger that uses stored kinetic energy to fully charge a mobile phone in up to two hours. Weighing only 150 grams, the wind generator may be a convenient answer for your next camping trip and adds another option to the growing number of ecologically friendly phone accessories such as solar powered phone chargers (which have limited functionality at night and in colder climates) and wind-up units.
The Gotwind wind charger uses a conventional horizontal axis wind turbine and has a propeller diameter of 30cm. The turbine then activates a 3 phase alternator producing about half a watt of power, which can be filtered into a rechargeable battery for use anywhere. Mobile phones can then be plugged into a control box on the unit for charging. Gotwind have anticipated that most makes and models of phone can then be fully charged in 1-2 hours. An additional feature of this clever portable generator is a tent mounting system that consists of four legs that allow you to secure it to most modern tents. You will never be away from a fully charged phone, even when away from all civilization, even though that might be the reason you went camping in the first place!
The lightweight wind generator is still in it’s prototype stage. Designed by Ben Jandrel, the device was initiated after Gotwind, (www.gotwind.org), which specializes in making electricity generating wind turbines, was approached by global communications corporation Orange. After seeing the work of the team at Gotwind, Orange decided to commission a prototype wind charger to unveil at the recent Glastonbury Music Festival, of which they were a major sponsor. These chargers were attached to sponsored tents, and provided an electricity free alternative for the duration of the festival. The prototype was completed in just four weeks and there are plans to mass produce these portable wind generators for release into the market in the near future. The cost of the units is not yet known.
The blades are flat and Bill insisted that they be dead flat and the more highly polished they were the more power they would pull.
A high % of the frontal area is covered by the blade area.
But Bill insisted that the inner 1/3 of the disc was basically irrelivant and the outer edge of the blades were at the maximum width... more force on the lever arm.
Bill also discovered that placing a symmetrical gap in the fan frontal area allowed the wind to pass through without avoiding the fan altogether by building up a pressure cone of resistance in front of the fan.
It gauls me that no one posts the efficiencies of their devices and certainly any certifying entity must list the efficiency.
Efficiency is scalable and that is the reason.
The huge 3 bladed fans or turbines have been tested in wind tunnels hence supercharging the results. In the real world the wind can walk away. The published efficieincie of them are erroneous.
Instead of being presented as the great hope for mankind, they should be scorned as perfect examples of very poor engineering.
Gizmag should demand efficiency ratings and put an end to all the nonsense.
Bill Dickens