Unreliable data from reliable sources The figures don t stack up Reality is less than 1 of the claimed effectiveness Body weight 70 kg x 10gravity 700 Newtons 5 mm travel 3 5 Joules per step 3 5 Joules lighting a streetlamp for 30 seconds Philips Fortimo LED streetlights consume 30 Watts 3 5 Joules will last about a tenth of a second The CNN Article 250 000 footsteps that was enough to charge 10 000 mobile phones said Kemball Cook So 25 footsteps per phone 87 5 Joules A typical mobile phone battery is 3 6V 900mAh 3 24 Wh 3 24 x 60 minutes x 60 seconds 11664 Joules I m tempted to delete the whole article as marketing BS