PHOS is a project by Gabriele Onnis, a Product Design student at the Istituto Europeo di Design in Cagliari, Italy. It's for a rather unusual sort of portable and rechargeable dual light.

"PHOS is a lighting system for home design, consisting of two bodies that generate and store energy through heat: two transportable light sources, where fire and light are inextricably linked, and where thermoelectric energy is produced, stored and used."

"The system consists of a bioethanol fireplace (fuel produced by the fermentation of biomasses) and a rechargeable lamp: the heat produced by the combustion of the bioethanol is transformed into electrical energy thanks to the Seebeck effect of the thermoelectric generators and the energy produced [which] recharges the battery lamp where a 3W LED is the source of light."

Onnis designed the project for his diploma thesis, and it isn't all theory: He collaborated with Italian energy provider Veil Energy to develop the thermoelectric system.