From Sam Edge, Ringwood, Hampshire, UK
The old chestnut of generating power from footfalls is back again (5 November 2016, p 23). Saying that “one footstep… yields between 10 and 30 volts” conveys little information. I want to know how much usable electrical energy one footstep generates.
A calculation of the mechanical energy dissipated by an average footstep tells me there is no possible way that this will ever be anything other than a curiosity. The environmental costs of construction and maintenance are going to far outweigh the energy produced.
