Phone-charging sleeping bag and shorts unveiled
Denim shorts and sleeping bags are being brought in to help solve the problem of phone charging at festivals.
They are designed to boost battery life by harvesting body heat and movement.
Their creators are using thermal energy for the sleeping bag and kinetic energy for the shorts.
Experts from the University of Southampton and Vodafone UK hope the "smart fabric" technology will provide a 24-hour power source for campers at outdoor events.
Users can already charge their mobile phones at recharge points at many festivals.
Bu if this technology was used it would mean festival-goers could charge their mobiles while walking from one stage to another, dancing or even when asleep.
The denim shorts incorporate a pocket using a fabric containing materials that turn body heat and movement into a charge.
Professor Stephen Beeby from the University of Southampton said: "We are exploring two specific technologies to charge the Power Pocket - thermoelectrics and kinetic energy harvesting.
"Both represent cutting-edge research around smart fabrics and we are looking to integrate these into consumer products, in this case, a sleeping bag and a pair of denim shorts."
Vodafone said tests showed that after a full day of walking and dancing, the "harvesting" material in the shorts would charge a smartphone for more than four hours.
Trials also revealed that heat generated during an eight-hour snooze in the sleeping bag added up to 11 hours to a mobile's battery life.
The shorts and sleeping bag could come into use by the end of the year.
In 2010 UK mobile operator Orange unveiled its Power Wellies, created in collaboration with renewable energy experts GotWind.