Visitors to the UK's best-known music festival are almost guaranteed three things - mud, loud music and a dead mobile device battery. Happily, Orange has increased the number of Chill 'n' Charge tents to help make sure lines of communication stay open and - in what is now becoming as much of a tradition as Glastonbury itself - the company has announced the development of a new green charging technology. Previous projects have included a Power Pump and last year's Orange Power Wellies, and the latest prototype charger is no less impressive. As the name may indicate, the Sound Charge t-shirt turns sound waves into electric charge, allowing the wearer to top up a device battery while thrashing around in the mosh pit.

Produced in partnership with renewable energy designers GotWind, the Sound Charge t-shirt prototype's modified A4-sized panel of Piezoelectric film at the front is said to act like an oversized microphone, absorbing sound waves and converting them via the compression of interlaced quartz crystals into an electrical charge. This is then fed into a small external reservoir battery (with visuals that pulse in time with the music) and the wearer can then pop a mobile phone or smartphone into the pocket above the panel, connect it up to the reservoir and top up the device battery using sound.

"In a vibrant festival environment such as Glastonbury, sound is such an obvious medium that it seemed like a natural fit to use it in the development of this year's prototype," said Andrew Pearcey from the UK wing of Orange, France Telecom Group's key brand.

The development team reckons that the t-shirt will generate up to 6Wh of power when exposed to sound levels of around 80dB - that's about the same noise level as a bustling city street and will not pose too much of a problem for Glastonbury Festival-goers. The reservoir should then get enough energy to fully charge two standard mobile phone or one smartphone, although wearers would most likely use it for a quick top up rather than a full charge.

Orange says that an interchangeable cable ensures compatibility with most brands, and the panel and electronics can be removed prior to washing - an important consideration for those attending a music festival. The Sound Charge t-shirts will undergo live testing around the Spirit of 71 stage, to see which of the acts prove most charge-friendly.

"Sound vibrations, particularly bass frequencies, will create enough shaking to produce electricity from a material as simple as piezoelectric film," said Spirit of 71's Tony Andrews. "It looks like it could provide a real solution to mobile charging and I'm interested to see how the Orange Sound Charge performs in a live testing environment such as Glastonbury."

I think that this is another great example of providing juice for mobile devices without impacting on the environment. If I was to voice any criticism at these innovations from Orange, it's that I can't get my hands on any of them - they're created to inspire future development rather than lead directly to consumer product manufacture. So, for now at least, music lovers will just have to take a solar charger along and hope that the typical Somerset festival downpour gives way to sunnier skies.

Festival and t-shirt updates will appear on the company's Glastonbury blog.

Meanwhile, the following video gives a short developmental overview: