December 5, 2005 – A Hong Kong company has built a prototype jacket that uses nanotechnology to allow the wearer to charge electrical devices such as mobile phones, said the South China Morning Post. After more than $15 million and six years, Nano Group Holdings claims the jacket enables a mobile phone to be connected to a pair of flexible, and washable, solar panels that charge the phone in five hours.

The panels are made from silicon particles that have been atomised to nanometers and sewn on the jacket surface. The inventor, businessman Charlie Chow, believes this is the first commercial application of such a technology, although several universities worldwide are understood to be conducting similar work.

Using the same photovoltaic principle that powers conventional solar panels on everything from desktop calculators to communications satellites, the flexible cells convert the energy from sunlight into electricity.

A strip of the material – called solar film – measuring 4cm by 25cm would generate a current of 1,500milliA – or roughly the equivalent of an AAA battery, at 7.2V. With two strips sewn onto a jacket, a mobile phone can be fully charged in about five hours on a sunny day, according to Chow. A person can also speak on the phone while it is being charged.

He said the technology had a wide range of potential uses, adding that it would be simple to use different adapters to connect to the solar panels to charge different devices including iPods, portable gaming consoles and personal global position satellite systems.

But the biggest obstacle facing widespread commercial application is cost. Inclusion of a pair of the cells would add at least US$15 to the price tag of a garment, something which has discouraged a number of brand names to whom the company has pitched the idea.

Nano Group has also built and pitched to the Hong Kong Police Force a visibility vest that uses the film to power a set of flashing lights. Mr Chow said the force had so far been reluctant to place an order because of its cost. It is hoped large orders would bring down manufacturing costs.

Currently the films are only available in brown, but scientists are working on making them in different colors to make them more fashionable. Eventually, Chow envisions large solar film panels providing clean and free electricity to remote rural villages in China.