Chargers draw about 10 watts - and take about an hour to re-charge a phone.
UK electricity is about 6 pence for a kilowatt hour, so you could re-charge 100 mobiles for 6p.
Ryanair employs 2,600 people, and if they each re-charge their mobile at work once a week, it would cost about £15 per week, a total of £750 a year
