Great idea! Questions are whether 5mm is noticeable to people who walk on it. Will it cause any imbalance to some people? If it does, it might become a liability.
Nonetheless, the idea is definitely worth exploring. Who knows, maybe after a couple generation, if not this first generation, will become part of the power source of our daily lives.
I would like to see numbers for the energy that can be harvested, and the capital costs needed.
The article is muddled: " 8 watts of kinetic energy can be converted over the duration of each footstep" Watt is a unit of power, not energy.
I did a similar calculation myself recently. I work out on a stationary bike that shows the power that I expend. I typically work out for 15 minutes at 100W power. The energy expended is 0.1KW * 0.25 Hours = 0.025 KWH, which is worth about $0.0025 at the current retail price for electricity, assuming 100% of the energy could be converted to electricity. That is very little value. And it is a fairly intence work out - much more intense than walking. And that raises the question that was previously asked - what will be the effect on the walker? My guess is that if more than a couple of watts or so of energy is harvested from a single walker, people will start to complain or will find a less tiring route to walk.
spot on.. they convert human energy to electrical energy. to walk on this floor one need to consume more energy as food than what he is used to now. again, after 1 hour of moderate workout at the gym, i spend like ~400 calories , which converts to just 0.000464888889 kilowatt hours. assuming a 20% conversion efficiency for piezo crystals, the numbers will be abysmal.
also this is not the first time this is being tried.. they tried this in tokyo/israel