Peter Ash, of Lawford, Somerset, attached a generator to his hamster's exercise wheel and connected it to his phone charger.
Hamster-powered phone charger
A 16-year-old boy invented a hamster-powered mobile phone charger as part of his GCSE science project.
Elvis does the legwork while Peter charges his phone in an economically and environmentally friendly way.
He came up with the idea after his sister Sarah complained that Elvis was keeping her awake at night by playing for hours on his exercise wheel.
"I thought the wheel could be made to do something useful so I connected a system of gears and a turbine," he said.
"Every two minutes Elvis spends on his wheel gives me about thirty minutes talk time on my phone."
The teenage inventor was given a C for his project and has been awarded a D overall for the course.