European Telco Orange is showing off an interesting phone charging prototype – a set of Wellington Boots with a ‘power generating sole’ that converts heat from your feet into electrical power to charge your battery-powered handhelds. You'll need to walk for twelve hours in your “Orange Power Wellies” to get an hour of battery life but we still think it's remarkable that such significant amounts of energy can be harvested from normal human activity. In order to decrease the length of time you need to charge your phone, try dancing or running, because the hotter your feet get, the more energy you produce.

The “Orange Power Wellies” were created in collaboration with renewable energy experts GotWind, with the vision of keeping Glastonbury Festival goers connected with their friends during the event.

After a full day’s festival frolics you can plug your phone into the power output at the top of the welly and use the energy that has been generated throughout the day to charge your phone. The power collected in the ‘power generating sole’ is collected via a process known as the ‘Seebeck’ effect that sees temperature differences converted directly into electricity.

Inside the power generating sole there are thermoelectric modules constructed of pairs of p-type and n-type semiconductor materials forming a thermocouple. These thermocouples are connected electrically, forming an array of multiple thermocouples (thermopile). They are then sandwiched between two thin ceramic wafers. When the heat from the foot is applied on the top side of the ceramic wafer and cold is applied on the opposite side, from the cold of the ground, electricity is generated.

The Orange Power Wellies are the latest innovation in Orange's efforts to find alternative, sustainable and eco-friendly mobile phone charging technologies that can be used at the Glastonbury Festival. Previous projects have included the Recharge Pod powered by wind and solar energy, the Dance Charger that drew upon kinetic energy created by dancing, and the Orange Power Pump which uses the energy created from a traditional foot pump and converts it into electricity.

Orange's Glastonbury blog will be launching in mid June.